Having an issue where my car has got a extremely high idle on start. somewhere up to 3200rpm. Dies off to about 1100rpm once the car is warmer. You think this would be my thermostat? changed it only 9000 k's ago.
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Having an issue where my car has got a extremely high idle on start. somewhere up to 3200rpm. Dies off to about 1100rpm once the car is warmer. You think this would be my thermostat? changed it only 9000 k's ago.
Not thermostat. IACV maybe...
but if it was that how would that explain the high rev's on start up and lower when it warms up?
mine rev's upto 2.5 - 3 on start up. it doesnt bother me, because when i warm it up it drops down to normal.
yeh same does mine...but i have forgies and not really that good to be reving that high on warm upQuote:
Originally Posted by xtat1k
Usually the FITV needs a clean or adjustment http://www.emotors.ca/Articles/97.aspx
Not sure if the B16A2 has an FITV though..
Awesome stuff...most probably is cos most crx's come with my motor. or very similar.Quote:
Originally Posted by EuroDude
but one more thing do u know where the FITV is attached to. like where do i find it so i can run threw the fix.
http://www.honda-tech.com/zerothread?id=1564019
that should help you out, if your engine is under 1996, you would have one, if over they dont
My engines 99-00 so then mine wont have one :(Quote:
Originally Posted by kerim
Why all your cars warmup at such high rpm ?
new CTR does this also, to about 2k rpm....
I dunno bro thats why i made this post...Quote:
Originally Posted by 1996ek1
Sounds like an Idle Air Control Valve problem to me too. Im with aaronng.
u runing after market ecu ???? it can be adjusted if you got after market ecu...
can u tell me where to find that?Quote:
Originally Posted by Paul1985
Theres a DIY on how to remove and clean one in the DIY section somewhere. I think it was either ECU-MAN or benjammin who created it. Have a quick browse for it as it will be usefulQuote:
Originally Posted by FastFwd
Its located just behind your intake manifold, between that and your firewall most likely. The IACV is a valve that allows a certain amount of air through by-passing your throttle body so the engine can run without using any throttle, this is what you call idle, your engine needs a little air and fuel to run even when your idling. So you could imagine if there was a problem with this valve then it would cause idle problems. It may just be dirty...
It quiet possibly could be a number of things though... Definately something to check out though. I cleaned my IACV on my DA9 and i still have a quiet high idle, up around 1500 RPM.
Hope this helps in some way??
Also check your throttle body...
must be ur idle air control......touch wood, so far my dc2r dont rev over 1500-1600 on cold start untill its warm and drops to 1000-1100
another thing, if your throttle body is stuck slightly open more than its supposed to be it will be letting air through and your engine will be revving up higher... could also be the issue although probably less likely...
Do this first: http://www.ozhonda.com/forum/showthr...highlight=iacv
Then do this: http://www.ozhonda.com/forum/showthr...highlight=iacv
thanks heeps guys it has to be something around there cos i recently put a new turbo in with water cooling and i 't peiced' off that water hose on the 2nd thred so im sure its got something to do with that..ill give it all a clean and see how i go. cheers everyone.
Guys The problem went away for a while but then came back and now its really bad, its embarrassing at like traffic lights etc. Got a vid of it.
http://i101.photobucket.com/albums/m...DSC03255-1.jpg
I did what a couple of you guys said and still didnt work. My mates a mechanic and he also said has to do with that water line that goes from the block to the intake manifold and when its blocked the idol goes crazy, but ive flushed it every which way and made sure water was flowing threw my turbo and back and all seems to be fine.
heres a vid of what happens.
http://i101.photobucket.com/albums/m...h_MOV03253.jpg
If you guys have any suggestions...also im not to sure how fast the water should be flowing threw that tube to the turbo and back...to me it seems fine but i dunno.
omg thats hectic! It sounds like the ECU is reading bad data and trying to adjust the idle in a loop. I doubt its a simple IACV or FITV problem, the effects of these going bad are much more subtle.
Have you tried resetting the ECU and checked for ECU error codes?
Nah got Power FC...hadnt checked the sensor checker thing on that....might try that i guess.Quote:
Originally Posted by EuroDude
Havn't downloaded your video, my bandwidth is third world! My first thought was maybe IACV, but it may just be an old fashioned intake leak somewhere? It might start out bad when cold, then get less bad as things heat up, expansion possibly causing the 'hole' to close up a bit?
If it's the IACV then it might go away if you disconnect the electical connector? Another check might be to take the IACV physically off and plug the two apertures in the plenum, then start it up to see whether this stops the high idle.
Nah its not VAC or intake leek...its more of a distinctive Idle change, not just a rumble going up and down. It used to be the case where when it was cold it would start doing it for about a minute then it would go away. but now when you turn the car on cold or hot it will do it and even threw a 30 minute journey it would still do it.
Checked the sensor setting on my Power FC and i don't know for sure what im looking at to see if anythings wrong but it seems to be fine.
ey man, try the idle sensor i think its called, mate had a similar problem on his dc2 where it just kept revving up and down, changed that and it was all good, give that a go
Do you know where thats located?Quote:
Originally Posted by kerim
not 100% sure but i think its behind the head, probably have to take it to a mechanic to do though
Just an update: took off whole intake manifold and throttleboddy, pulled everything appart. cleaned it all spottless. checked the throttle sensor etc and everything i did still doesnt work.
But now its idling fine, not going up and down but its idols past 4000 with the idol sensor in or idles just over 2500 with the sensor out Not just unplugged but completely removed....so to drive it ill just remove the idle sensor for the time being. I also by passed my turbo from the water lines and ran a stock tube from the head to the intake manifold as the pictures above...and still didnt work. soo yeh i dont think it has anything to do with that.
I think its electric or something. Dunno if any of you's know the POWER FC much but if someone could tell me if theres an Idle changer or something on that. let me know
Cheers
If it's 'idling' that high with the butterfly properly closed (you did check that I assume, but have you checked the butterfly spindles and their bores? these can wear causing air to leak and erratic idle problems) then there must be an air 'leak' somewhere past the butterfly. If we assume that all the gaskets etc are fine, then the 'leak' is coming from a malfunctioning component, or a component that is being 'told' to do the wrong thing.Quote:
Originally Posted by FastFwd
It has to be a device designed to allow air to bypass the butterfly to allow that high an idle. The only thing that comes to mind is the IACV. Have you tried disconnecting it, or blocking it's air passages?
OK......Last night i unbolted the the throttlebody, removed the Idol control unit, and everything else attached to the throttlebody. Cleaned it all up like new and put it back on. This has stopped the Idling up and down issue..i think but now the idol wont stay under 5000. when i take the idol control wires off it will drop to about 4000. drove it round today and it ran like shit....doesnt even have any power.
So tonight i pulled off the IACV like JohnL has said...i found a link which helped me out... http://www.team-integra.net/sections...ArticleID=1174
Did exactly what the steps said...well i probably should have left it to dry for about 20 mins...i put it on in about 5 after thoroughly cleaning it. anyways put it all back started the car up....idols at around 4000, then when it gets warm goes down to about 2800 but when i plug in the IACV wires it goes upto almost 5000 again. and now my car is skipping like crazy...barely drivable. F$%K i should have left it.... I can usually fix most things but this is driving me up the wall...think i might take it to a mechanic. gonna have to tell him everything ive done :(
Also guys...on my power Fc i have found the idle control settings...they are currently set at 970rpm...put them up and down just to test and nothing happened. soo i put it back to 970rpm.
OK, so disconnecting the IACV connector doesn't stop it happening, though it does make some change. Whether the IACV is faulty - or is perfect but being 'told' to do the wrong thing at the wrong time, to make sure that the 'leak' isn't happening through the IACV (whether the IACV is faulty or not), try fitting a 'blind' gasket at the IACV / plenum faces.Quote:
Originally Posted by FastFwd
Making such a gasket is dead easy, take the IACV completely off the motor and make a paper gasket using light cardboard (or prefferably proper gasket paper) that will block the inlet and outlet ports in the IACV. The only holes in the 'blind' gasket will be the two bolt holes, so no air can pass into or out of it. Refit and start up.
If the fast idle problem goes away then the problem must at least be associated with the IACV, but may or may not be the IACV itself. At this point you would need to swap the existing IACV for a known good unit (without the blind gasket), just to see if changing it fixes the problem. If it does then your IACV must be faulty, but if it doesn't then your IACV is probably OK but being 'told' the wrong thing by the ECU, which itself may be being told the wrong thing by some sensor....
If fitting a known good IACV doesn't fix it you might be looking at the ECU, but more likely one of the sensors informing the ECU. This still doesn't conclusively mean there might be no other point at which a leak might exist, possibly a leak inside some sensor on the engine side of the butterfly(?).
You can drive the car with the IACV disabled in this way (with blind gasket fitted), but idle will probably be low and definitely low when you use air-con or other auxilliary loads are on the engine. You'll also probably find you have some drivetrain 'snatch' that wasn't there before, which is a bit of a pain but doesn't really hurt anything.
Did you try adjusting the Throttle Idle screw?
JohnL thanks for your reply, I think im on the same steps as you. i didnt actually make a gasket but i thought if there may be a leak in the IACV then i probably should ensure that its not there. soo i used some silicone gasket maker. Put that on and waited bout 5-10 before i started the car. the gasket GOO has worked for me before in similar situtions so that would be the same effect as your Motor cardboard idea (but yeh i know what u meen by the cardboard, used that stuff before).Quote:
Originally Posted by JohnL
But i think yeh it must be something with the IACV...thats really the only thing changing when i plug and unplug the Sensor from it. Going to take it to my uncles (mechanic) tomorrow and ill pick up another IACV from a wrecker on the way and give that to him.
Eurodude, i dont want to sound like a asshole by saying this and dont take this in the wrong way. But do you really think if ive done all the things ive done to check whats wrong you would have thought at one point i would have tried the idle screw. So your answer is YES!!Quote:
Originally Posted by EuroDude
I'm not sure I follow what you mean about the "silicone gasket maker", you need to block off some substantial holes (IACV ports), and I'd have thought that even with a few minutes to cure (which would take a fair while longer with a big slug of silicone) the silicone goo would tend to get 'sucked' into either the plenum, the IACV, or both? If you sucked it into the IACV then you could bung it ip pretty comprehensively I suspect...Quote:
Originally Posted by FastFwd
Do you mean you deliberately bunged up the IACV by filling it with goo?!
Just a thought. Have you checked the rubber gasket between the IACV and plenum? It could have a leak either to atmosphere around the edge, or from port to port (i.e. air could pass between one port and the other without being metered through the IACV).
Personally I won't let silicone gasket goo anywhere near my engine. I'm told that if it gets into the combustion chamber that it's burnt gasses can 'poison' the cat converter and impair it's function or even make it not work at all. From personal experience I know that it can get 'loose' inside the engine, not a good thing, though in a modern engine it would get caught by the oil filter before doing any damage... probably. It might possibly block the oil pump ports if there was enough of it...
When I used to work in a motor museum we had some come loose inside the engine of a Bugatti Type 35B, caused some issues as the oil filter was non existant (we didn't put the silicone in there, it was somebody who worked on the car before us).
My favourite gasket goos are; 'Aviation Gasket No3', or 'Blue Hylomar', both are 'non-hardening' and dissolve if they get into the oil but not if they stay in place at the gasket. Silicone is fine for gearboxes...
Hey bro, sorry to say but the only thing that can explain an idle that high is air getting into the intake from somewhere, pm me if u still got the problem and i will tell u a few things to check.
Quote:
Originally Posted by JohnL
Nah nah u got me all wrong, i am using BLUE HYLOMAR, i checked the gaskets that i currently have and they seemed fine, so i just added some gasket goo just to seal the deal. not much just around the edges. I think the next thing i should do is remove the IACV and block the holes with something and test it like you said.
So sorry im coming to the conclusion that if the idol control seams fine and the idle screw is all the way in that something has to be leaking from inside the intake manifold but before the butterly and really theres only the IACV, throttle body (gasket), Butterfly (loose), or any of the vac lines attatched that could be causing the problems.... OR ECU (sensors)
And that when i plus in and out the IACV even now its making the idle rev to another 1000-2000rpm that is must be something there.
Sorry maybe im just thinking to myself but correct me if what im saying is wrong?
reece, check the hose coming from the box on your crankcase, make sure that is all ok, i know it may be too loud but see if you can hear a leak when you block the throttle body with your hand. and check the gasket in you throttle body and where the intake manifold bolts to the head aswell, i strongly believe there is air coming in from somewhere.
Yeh blocking the throttleboddy might show a leek...but nah its not the bolts, i removed the throttlebody the other night and cleaned everything out and made sure everything was tight. after work tomorrow ill try taking off the IACV and blocking the two wholes at the back and seeing how it idles then.Quote:
Originally Posted by B18cEG
You mean after the IACV?Quote:
Originally Posted by FastFwd
Maybe the IACV is working to some degree but not seating, i.e can work a bit but for some reason sticks and can't close off when it's told to? If this is the case it's a bit strange though that the ECU wouldn't detect the high idle and tell the IACV to remain closed (or as closed as it can be considering it may be sticking open), thus causing no change when the IACV is connected?
Perhaps the IACV is 'stuck' wide open when no power is getting to it, but when it gets power it can close, just not all the way? If so a bit odd as I would have expected the IACV to be closed with no power...
I cleaned out the IACV pretty good, but there was a HEX Key on the one side which i didnt have to be able to pull the whole thing apart. Do you need to pull this thing out to give it a good clean? im heading to a Honda dealer today to buy new rubber rings for the IACV, and throttle body gasket and few other bits and rubbers/gaskets connected to the intake manifold to ensure theres no leeks.Quote:
Originally Posted by JohnL
I need to ask how does the IACV adjust the idle when its connected to two ports in the manifold and connected to water? does the water just cool the IACV? what is the purpose of the water?
Ok JohnL you would know this. Ive done some troubleshooting with some help of searching around google for a few hours last night.
Ok soo today this is what i came up with. This is before i pulled apart the IACV:
http://i101.photobucket.com/albums/m...c/DSC03260.jpg
Now ive cleaned it up. I got Throttlebody cleaner and left it soak submerged inside for about 45 minutes. Pictures below:
http://i101.photobucket.com/albums/m...c/DSC03261.jpg
http://i101.photobucket.com/albums/m...c/DSC03262.jpg
http://i101.photobucket.com/albums/m...c/DSC03263.jpg
http://i101.photobucket.com/albums/m...c/DSC03265.jpg
I also Sanded back some of the rust on the back water casing so it would sit nice and flush.
Then when i put it back on still nothing. Reving up to 5000rpm idle. I read up on the net that if you plug these two holes in the picture below it should sit at stock idol which is what the screw is set at.
http://i101.photobucket.com/albums/m...c/DSC03268.jpg
The top hole didnt make any difference but the bottom one is sucking all the air threw into the intake so where ever that air is coming from is the problem. Which i seem to think its the IACV. Heres a movie below to show you what i meen.
http://i101.photobucket.com/albums/m...h_MOV03266.jpg
If anyone can tell me which hole goes to the IAVC and which doesnt that would be great. Because if that below hole is the IACV even after cleaning it twice like i have it has to be replaced.
Ohh also one thing i did check is the Voltage coming out of the sensor wire. it was 2.2-2.5 volts on Accessory i didnt get a chance to start it but i just wanted to make sure the thing was showing some voltage to check to make sure the wire wasnt broken.
the hole that you were blocking goes to the iacv, the water port part is just for cooling, inside it there should be like a white plastic spring like thing (like an accordion) with a metal rod through the back of it, when you look into the holes you should see it and you just need to see if it moves freely when you push it, be gentle dont rip it. when your car is cold it should open to rev a little higher, when worm it should shut or nearly shut, it seems like your is stuck open.
I haven't attempted to dismantle an IACV. I'm sure you could ensure a more thorough clean if you did, but there may or may not be issues when re-assembling it...??Quote:
Originally Posted by FastFwd
The water lines are irrelevent to your problem. They don't cool the IACV, their only purpose is to warm it, I assume for the same reason there is water heating for the throttle body, i.e. to prevent icing up in freezing conditions.
The IACV works by drawing air from a port that starts just before the butterfly, air then passes through this port (which is inside the plenum casting, but closed to the plenum chamber proper) to the end of the port which exits at one of the ports in the IACV. Air is then metered as required (as 'instructed' by the ECU) through the IACV and out the other IACV port into the plenum chamber and from there into the cylinders.
Ok dude i fixed it...the Lower port that i blocked went to the FITV. not the IACV. but i opened it back up and the thred seems to be a little damaged so this afternoon i went and picked up a new internal part from a wreck put it in screwed it up and DONE!! works.....1100RPM HEAVEN....
But now i have a different problem. i dont know if i've put my ECU out of wake but it seems to be spitting lots of fuel...running extremely ritch...to the point when if i put my throttle down more than 20% it will skip until i take my foot off the throttle...its defiantly drivable now but i cant put my foot down unless i take it easy and bring up the revs for a bit. I think its ECU but i dunno could be something random now
is it definetly running rich? is the engine running stable or does it sound like maybe one cylinder isnt firing? it doesnt sound like a wrx when its skipping does it?
Nah dude on idle its completely fine...its not Sparks or leeds if thats what your thinking.
Its just when im driving...If the car is in nutral i can rev it and it will be like normal but when im driving and turbo is spooling etc it will skip when i put the eccelerator down to much. almost JUMPY somtimes plus is has like NO POWER wat so ever
Progress! 1100rpm still seems a bit high, but way better than what you had before!Quote:
Originally Posted by FastFwd
As to running rich, don't know why, sounds like a seperate problem. Maybe try resetting the ECU?
sounds like fuel issue possibly, on my civic (NA b18c engine) when i got it back from the repair shop they put the timing out by one tooth on the crank and it idled fine and sometimes drove fine, other times it would shoot 1 meter flames out the exhaust and rev like a pig and have NO power, just make shure it hasnt skiped a tooth on the belt (use timing light) other than that make sure you pluged everything back in (from experience lol) if all else fails it may be ecu related, did you change anything on the ecu? thats the only thing to think about
Make sure that the MAP sensor is plugged in properly and that you didn't accidentally knock it when you were taking the IACV out.Quote:
Originally Posted by FastFwd
Had a thought, try this; attached to the fuel rail there is a return valve that allows excess fuel pressure to bleed off back to the tank. It has a low pressure return fuel line at one end and a rubber vacuum tube at the other. This tube is attached to the plenum. This thing works is to keep fuel pressure at X psi above manifold pressure, whether this at any moment be at or below atmspheric (or in your case with turbo, above).Quote:
Originally Posted by JohnL
Inside this valve is a diaphram, if this diaphram leaks then pressurised fuel from the rail can leak into the plenum through the vacuum tube. The obvious result will be running rich, which may be worse at certain rpm than at other rpm.
I suppose it also could be that if this valve isn't working (but not leaking as described), that the fuel pressure might be too high, which could also cause rich running...?
Diagnosis? It might not be a good thing to block the vacuum tube, you might try it but I don't know what this will do (probably cause a too high pressure?). Try pulling the vacuum tube off and sniffing it for a petrol smell (it shouldn't smell of fuel), or maybe some fuel may even leak out?
Hey that is very similar to what my car is doing...and yeh it did shoot a one meter flame out the rear. the car feels all normal if you tred lightly on the accelerator but if u push to hard it feels like it will almost die because the skips are soo huge. but then even if u tred lightly you can sorta get passed the skipping stage which usually is at around 4000rpm. but it can be at ANY RPM its just usually around there. but even still it just feels like the turbo is there pushing pressure into the motor (more air) but something isnt doing what its supposed to, to compensate for this extra pressure. But how would it skip a tooth on the timing belt? ive never heard of a car doing that.Quote:
Originally Posted by B18cEG
Did you get your timing belt replaced recently? Did any workshop have to remove the timing belt to access other parts?
I give that a go tonight. also wanna check sparks. maybe give them a clean, i dont think thats the problem but it just feels really weird. It actually feels like all the SPARKS just turn off if u push the Accelerator to hard....Its hard to explain ill take a movie tonight...But yeh i think the best bet is Vac lines. Maybe even something with my fuel pressure reg. One thing i have noticed is ever since i took of the fuel feed to the left side of the fuel rail (standing looking towards the motor) is hasnt been right since then. I had to take that off to get it out of the way to remove the throttlebody. cheersQuote:
Originally Posted by JohnL
not sure how it skiped a tooth if it has but its not impossible, if you can see ur cams make the pointers point to up and look at the crank pulley and there should be a few line and a centre line on it, the centre line should line up with some plastic markers on the timing belt housing when the cams mark is up.
Well ill get that checked out. spoke to my uncle bout that and he doesnt seem to think its timing.
Brought it to him today and he said it could be 3 main things he could think of...
* ECU
* Map Sensor
* Dizzy
* Plugs (but thats a maybe)
I swapped ECU with my old stock one and went for a drive...same problem so its not ECU. pulled out the plugs, they only 4000k's old but i gave them a clean and chucked em back in. Map sensor i pulled out and checked but i dunno might need replacing. an Dizzy god i wouldnt know how to check it. Dont you need to get the voltage specks of the car then check each section with a voltmeter or something.
Other than that my uncle doesnt seem to think it could bee something i did while trying to fix the Idle issue.
Also i did what JohnL told me. Crimped off the vac supply direct from the plenum to everything including fuel pressure reg...still same issue... I think timing will be good to check. If you guys could give me few other things to check...Like an elimination process. That would be great.
I generally dont let workshops work on my car unless its something that ive tried doing and i cant.Quote:
Originally Posted by aaronng
Sorry been burned in the past. Blown motors, cracked radiators, scratch interior and so on plus no refunds. Seems every time i get someone to look at it, they F$%kd something else in the process.
But yeh nah i havent change the belt since the rebuild 9-10thou ago
So that rules out the timing belt unless it was very loose and the belt tensioner was already maxed out. But check it anyway.
Ill check it to be sure anyways but i dont think it was that as the car has been running perfect for weeks until i fixed the idle issue.Quote:
Originally Posted by aaronng
have u got a multi meter? check the leads and they should read about 15kohms per meter of ignition lead, if its to do with voltage from the coil, i can let u borrow mine to test out if its the same as the one from a b18c, i changed it about 5000k's before removing the motor. i live in joondalup.
Borrow your coil? or the volt meter. I have a volt meter but coil could be the prob...I live in carramar, like 5 mins from joons. When can we meet...?
you can borrow the coil, its pretty much new. i thought u used to live in currumbine, anyways u wanna come past alberts joon today? let me know i let a PM.
All K20s do it. It only takes about 2-3 minutes. I always let my car warm up before driving. I usually start driving when it drops below 1,500rpm.Quote:
Originally Posted by 1996ek1
what does this have to do with anything?Quote:
Originally Posted by m0nty ITR
Because he asked. I quoted to avoid confusion. Should I have highlighted and selected bold text also to avoid confusion?Quote:
Originally Posted by B18cEG
Guys on topic please.....
aaronng said:
Hey that is very similar to what my car is doing...and yeh it did shoot a one meter flame out the rear. the car feels all normal if you tred lightly on the accelerator but if u push to hard it feels like it will almost die because the skips are soo huge. but then even if u tred lightly you can sorta get passed the skipping stage which usually is at around 4000rpm. but it can be at ANY RPM its just usually around there. but even still it just feels like the turbo is there pushing pressure into the motor (more air) but something isnt doing what its supposed to, to compensate for this extra pressure. But how would it skip a tooth on the timing belt? ive never heard of a car doing that.
If its running very rich its not too surprising if it shoots the occasional flame (not good, slightly embarrassing, but kind of cool!). You’re dumping a lot of hot un-burnt fuel through the exhaust in an oxygen deprived environment, then at the end of the pipe it finds oxygen and bang!
(I once had most of the pipe fall off my ‘Nota’ clubman sportscar, giving me an unsilenced pipe about two feet long exiting the side. The engine in this car (a highly tuned A series BMC engine, like a Mini’s but from an Austin Healey Sprite) could dump a lot of fuel down the pipe due to the valve timing. Sans most of the pipe, on the overun it would explode with very load bangs, shooting the most amazing blue flames! It made the best sounds reverberating in tunnels, hard on the throttle through the gears and then backing off with explosions, the flames lighting everything up like lightning flashes! Pity I couldn’t have left it like that for more than a day, but fun as it was it was too much, too embarrasing and made me police bait!).
If your engine is actually cutting out rather than just losing power and blowing black smoke it must be very, very rich. The cutting out (“skipping”) problem may be unrelated, but I doubt it, it’s too much of a co-incidence that it started misfiring when it started running rich.
Jumping a tooth or so on the belt would be rare but not unheard of. I’d be surprised if this were the problem, the belt would need to be quite loose I’d think. I’d be surprised if the timing were out that it would cause the engine to actually cut out rather than just lose power and run rough, but you never know?
I give that a go tonight. also wanna check sparks. maybe give them a clean, i dont think thats the problem but it just feels really weird. It actually feels like all the SPARKS just turn off if u push the Accelerator to hard....Its hard to explain ill take a movie tonight...But yeh i think the best bet is Vac lines. Maybe even something with my fuel pressure reg.
Rich running could cause problems with the plugs sooting up and not firing, could be contributory?
Maybe, (thinking out loud), perhaps it’s not really running rich (?), but the plugs may simply be failing to ignite the fuel in the chamber, then the un-ignited fuel gets dumped into the exhaust, which then occasionally ignites when it exits the pipe?
The higher the compression pressure in the combustion chamber (which maxes at peak torque output with a more open throttle, typically in the middle of the rev range more or less, depending on tune) the more easily the spark will ignite the mixture, but, the higher the compression pressure the more likely a plug will fail to actually produce a spark (this is why a bad plug might make a spark outside the motor but not work when fitted to the motor, i.e. higher air pressure inhibits spark production). This might be caused by the plugs themselves, or it could be that the voltage and / or amperage being fed to them isn’t up to scratch? If this is the case, then it could be anything from the plugs back to the dizzy, e.g. leads, ‘igniter’, etc…
A turbo motor will produce very high compression pressures (especially at peak torque output), so depend heavily on the ignition system providing a very strong spark.
Is it blowing a lot of black smoke? If not then it’s probably not running rich (at least not rich enough to cause your problem). If it might not be running rich then this begs the question; are you absolutely certain that it is rich, and might not possibly be running lean?? If it is then this is a much worse problem than running rich, it can easily wreck the engine (especially a supercharged engine, and your turbo is a kind of supercharger, to state the obvious).
Running lean can also cause misfiring, but I wouldn’t tend to associate it with shooting a flame out the pipe. However, if it runs SO lean that the fuel isn’t igniting in the chamber (either because of the leanness, ignition problems, or both), then you’re still injecting fuel but you’re dumping that un-burnt fuel down the pipe, and it may then ignite when it reaches the end?
It occurs to me that if it were running lean then it might fit one of your symptoms; if you accelerate slowly and it doesn’t misfire, but if you accelerate harder and it does, this might mean that the mixture isn’t richening up enough under harder load, or that it might be richening up, but the base mixture is so lean it doesn’t richen up enough to prevent the engine cutting out (but on the other hand, if it is running rich then the enrichment process might cause it to run so rich that it cuts out?).
This is why carb engines have an ‘acceleration pump’ that squirts an extra shot of fuel down the throat of the carb on hard acceleration, i.e. to richen it up for the extra demand / need for additional fuel required on harder acceleration (mixtures significantly above adiabatic are required for hard acceleration, but not for cruising on light throttle, or even consistent high speed with a wide open throttle). If you disconnect the acceleration pump on a carb, then with careful / gentle throttle you'll be able to accelerate sedately right up to max speed and / or max HP, try harder and acceleration will be poor at best, but at worst the engine will shut down until you back off. Fuel injected engines do a similar thing, but the enrichment is controlled by the ECU. Remember that the ECU relies on what it’s told by the sensors.
One thing i have noticed is ever since i took of the fuel feed to the left side of the fuel rail (standing looking towards the motor) is hasnt been right since then. I had to take that off to get it out of the way to remove the throttlebody. Cheers
What???
Hope this helps!
Regards,
John.
Johnl Thanks heeps for all your help defiantly giving you a rating if i can find out how...B18cEG (jason) came round last night and help me fix it. He bought over his dizzy, leeds, sparks, map sensor...tried them all and we couldn't fix it.
But after alot of fiddling we found my Fuel pressure reg was running 20-25psi...I don't know how it go that low. i haven't touched it since the last place did a tune. So we pumped that upto about 48ish atm. And the other issue was the "throttle position switch" wasn't dialed in correctly so it was giving my ecu the incorrect amount of voltage..soo we set that correct and now she runs like a dream....
But i dont think i would have been able to fix it last night without jason.
Hooray! Enjoy your car...
cheers!!
Nice one!