Urgent rev hunt issue!

Hi guys, had a photo shoot tonight in dubbo. and i now have issues where if im doing under say (including being stationary, either in or outof gear!) 5-10km/h the car rev hunts from between 1500-2000rpm, while trying to drive the car will jerk back and forward as it bounces between 1500-2000rpm until speed is picked up! i have not changed anything tonight, i did not wash my engine bay, i have not changed anything. i was not thrashing the car, as we were taking photos and the police were present! i checked my tps and speed sensor and all other sensors where plugged in?

what is going on??

also add! no cel light is on, and the car idle's fine, and after jerking goes away also drives fine!

Hehe same issue as mine

(b16a2)

Ive been investigating this issue for a while!

First things first!!

1.check your cooling system (bleed it properly)

2. If your car has an FITV clean that up

3. Tighten the FIV if you have one!! up if you need to check anymore info don't hesitate to click the link!


http://m.youtube.com/index?desktop_u...?v=L788jKEVblY

I found this helpful

Thanks

Do the usual. Clean IACV etc.

ok update, had code 7 tps? thought i might try calibrate it, couldnt get any volts at all, middle pin with positive point of multimeter negetive on negative battery terminal. ignition on, no volts no matter where my tps was? took it off visibly seemed fine, cleaned up with contact cleaner. no change, thought i might clean throttle body with carby clener,

WEIRD PART!!!!!!!! AS I WAS SPRAYING CARBY CLEANER INTO THROTTLE BODY, car would rev freely and quickly as per normal conditions, as soon as i would stop spraying it, would start to rev hunt between 1500-2000rpm?

also played with/cleaned MAP sensor? no change.

car is also now surging while driving normal? i could be sitting on 50, then with no change of foot would just die;adjust foot and would raise back up to 50 ect

Ignition system

which bit?

and y would spraying caby cleaner down the throttle body fix the issue?

Sounds like a fuel or igntion issue. Carby cleaner is extremely flammable, so it'd be igniting in the cylinder with nearly compression alone. This would be stabilising the idle.

Check fuel pressure, check plugs, maybe change the dizzy cap and rotor button, the coil, etc etc.

Sent from my Xoom

the car idles fine. its when i try to rev it is when the problem starts?

and it stalls if it just spray it down. i have to rev it so it doesnt die. so it cant be that flammable.

2 holes In the throttle body 1 on top 1 on bottom now while the car is running place your finger over the top hole see what happens, than place it over the bottom hole if it stops hunting when finger Is over bottom hole pull the unit that's on the bottom of the throttle body a coolant line runs to it... Take the 2screws of the plate at the end of it.. Theres a thing inside tighten it up.. that fixed my hunting problem on my b16a2

Quote:

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Originally Posted by sxmachine

2 holes In the throttle body 1 on top 1 on bottom now while the car is running place your finger over the top hole see what happens, than place it over the bottom hole if it stops hunting when finger Is over bottom hole pull the unit that's on the bottom of the throttle body a coolant line runs to it... Take the 2screws of the plate at the end of it.. Theres a thing inside tighten it up.. that fixed my hunting problem on my b16a2

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If it's like my b16 99" there is only a top hole as there is no FIV (bottom hole) on the throttle body :) just a heads up

its a b18cr 96 spec?

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Originally Posted by Alexplicit

its a b18cr 96 spec?

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Sweet u should have an FIV and FITV mate look at the video I linked you to and give it a shot!!!

b18cr dont have fitv afaik

As far as my research goes b series motors from early 90-96 came out with the FITV -.-

everything i can find, says b18cr doesnt have it.

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Originally Posted by Alexplicit

everything i can find, says b18cr doesnt have it.

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go have a look and confirm...

harder said than done :( car is out of town atm, i stopped driving it. dont wanna run the risk of damaging anything further.

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Originally Posted by Alexplicit

harder said than done :( car is out of town atm, i stopped driving it. dont wanna run the risk of damaging anything further.

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Sucks your car isnt nearby mate! Well if you still need this info I am going to try these troubleshoot guides and hope to fix my issue as I'm having the same issue as you!

P.s if your like me and don't have the FITV And that other stuff just try all the steps u can :(

Extract from:http://ef-honda.com/ben/Badidle.php


First things first, don't skip any of these steps. From what I have read (and experienced) usually small dumb things cause these problems so don't overlook anything. Also refer back up to the pictures if need be.

1) Check your vacuum routing. On the underside of your hood there should be a vacuum diagram. If there isn't a diagram under there, there is one in a Helms, Chiltons, or Haynes manual for your car (you should have one of these anyway). Remember, ANY extra air will confuse the ECU. Check for cracked or bad vacuum hoses. If in doubt just replace the hose, they are cheap.

The PCV valve could also be the culprit. Take it out and examine it. If it is cracked it could be causing a vacuum leak. Replace the peice if you arent completely sure it is ok (the helms/chiltons/haynes manuals tell you how to check it).

2) Check to see that your throttle plate is closed all the way. Take your intake off at the TB and check to see that nothing is blocking the plate. If nothing is in the way and it isn't closed all the way, loosen your throttle cable.

3) Check to see if the nuts holding the TB and the IM on are tight, this was the source of my idle problem. If they are loose, tighten them.

3.5) Check the Idle screw. Its on the top of the TB right next to the red vacuum line in the first picture. Its a flat-tip screw and most TB's have it epoxied over. If your screw is not epoxied over try adjusting it.

4) Bleed your coolant. Some air bubbles may throw the FITV off and keep the valve open.

5) Take the 3 10mm bolts out of the FITV (you don't have to take off the coolant lines). Then take off the 2 8mm bolts off the plate on the back of the FITV. Once the plate is off you will see a white plastic thing, screw that all the way in. This causes a TON of people's hunting idle problems (it's a source of a vacuum leak). Put the FITV back on and start the car up. If it still idles bad go on. Here is a writeup on the FITV.

6) Clean the IACV screen(s). See Oz's write up on G2IC.

7) Make sure your car is completely warmed up. With it running, take the intake off the TB. There are 2 holes right in front of the throttle plate, these are the holes that feed the IACV (top hole) and the FITV (bottom hole). With your finger, cover up the bottom hole (it should NOT be sucking if your car is warmed up). If the idle goes down the FITV is to blame, either get a new one or take it apart and screw the valve completely closed (I have only read of people doing this, so I don't know exactly how. Also, you will have to keep the engine speed up yourself when the car is cold).

Next cover both holes up with your fingers. The car should sputter and die (or almost die). If it does then the source of your crappy idle is the IACV. Replace it. If you want you can test the IACV. Shut the car off and put + battery voltage to the blk/yel terminal (on the valve) and momentarily touch ground to the blu/yel side. When doing this the valve should click, if it doesn't, replace it.

If, when covering both holes the car still has a high idle, you have a vacuum leak somewhere. Again check the IM and TB nuts. You can spray carb cleaner around those areas and if any gets sucked in (the engine will rev) you have found your leak. Another source of vacuum leaks are where the FITV and IACV connect to the IM. Either replace the gaskets or use silicone gasket sealant.

8) If nothing has worked you should test your TPS. Probe the middle wire on the TPS plug (with the key on but not running, and the plug still connected to the sensor) with the + probe on the volt meter, and the neg probe to ground. You should have .5v with a fully closed throttle plate and 4.8v with it wide open. If the TPS is off, replace it. My TPS was .425v to 4.55v and it idles fine now so I don't know how big the margin of error is. Also, it is pretty rare for these to go bad.

9) If, still, nothing has worked you might want to try a new ECU. This also is very unlikely, but worth a try.

10) If it still idles bad, go through the steps again.

thanks for the that! ill give it a go :)

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Originally Posted by Alexplicit

thanks for the that! ill give it a go :)

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No problems! Here to help I'm actually having the same issue with my fresh b16a2 lol so any info I find that could help I'll keep u posted

ok so i dont have FITV, so i cleaned out my iacv, problem is still there :(.

i think the thing we should be concerning ourselves is the fact the issue dissappeared when i sprayed carby cleaner down the throttle the issue went away! its soooo weird!!

Quote:

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Originally Posted by Alexplicit

ok so i dont have FITV, so i cleaned out my iacv, problem is still there :(.

i think the thing we should be concerning ourselves is the fact the issue dissappeared when i sprayed carby cleaner down the throttle the issue went away! its soooo weird!!

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Lol I sprayed the carby cleaner down my throttle body and it nearly stalled also but the problem was always there I changed my idle motor last night and still the issue is arising, My mechanic switched over a few plugs (electrical system) and the idle issue went away which was weird he seems to think my issue is caused by faulty wiring harness or incorrect locations

as your spraying it rev it.

and what plugs did he sitch over?

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Originally Posted by Alexplicit

and what plugs did he sitch over?

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Am Not sure what he switched over but when he switch the plugs to car idle at 900 rpms and never lagged when coming off the pedal and went straight down to 900! Drove well but when i started it about 20 mins later when the car was colder the idle was at a shaken 600 rpms even after revving it. This issue is giving me the shits I wish it never occurred ./

:(hmmm grr this is annoying..

try and find out what plugs he changed.

ALSO, does anyone know how to set the air/idle screw back to standard. i may have adjusted it thinking it could be the source of my problems?

What engine do you have? ill check my manuals and see if ive got one on your engine but if your not very mechanicly inclined you should take it to a mechanic to have it set properly.

Also i noticed on the first page you said you have a CEL reporting a faulty TPS, then when you tested it, it reported no voltage. Did you check the plug/connector for the TPS was getting the correct voltage? if it is then you need to replace your TPS as that has potential to cause your car to rev hunt while accelerating as your ecu is not getting the correct throttle position signal.

Quote:

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Originally Posted by TbM

What engine do you have? ill check my manuals and see if ive got one on your engine but if your not very mechanicly inclined you should take it to a mechanic to have it set properly.

Also i noticed on the first page you said you have a CEL reporting a faulty TPS, then when you tested it, it reported no voltage. Did you check the plug/connector for the TPS was getting the correct voltage? if it is then you need to replace your TPS as that has potential to cause your car to rev hunt while accelerating as your ecu is not getting the correct throttle position signal.

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^^ this guy is a legend with the info he is like a Honda god when it comes to technical information

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Originally Posted by hasto2770

^^ this guy is a legend with the info he is like a Honda god when it comes to technical information

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Agreed !!! Heaps good on the info

ill recheck, car is currently in sydney.

update, flushed cooling system. no change.

whats rev hunt???

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Originally Posted by Vtakk

whats rev hunt???

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Its when the engine wont hold a consistant RPM, instead of sitting at say 750 RPM the engine RPM will surge up and down. search Youtube for "idle hunting honda" and you should get an idea of what its like.

my car doesnt surge on idle, only when its in neutral and i press the accelerator. wont rev past 2k and bounces form 1500-2000RPM

Quote:

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Originally Posted by Alexplicit

my car doesnt surge on idle, only when its in neutral and i press the accelerator. wont rev past 2k and bounces form 1500-2000RPM

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I was just using that example so Vtakk can see what its like, couldnt find a youtube video of it happening while driving/accelerating so figured that was better than nothing.

Have you checked the TPS again yet or the car still in sydney? I usually fix the cause of any CEL first and rule it out as the cause before trying to diagnose a car then if the problem persists i would follow Trism's advice and look at the fuel and ignition system.

Do you still need the procedure to set you idle as per honda specs? let me know what car/engine you have and ill see if ive got the info laying round and ill pm you it if i do.

yeah i do, i got cocky and played with the screw, it was quite soiled, so i cleaned it off, car seems to whistle really loud now :P

UPDATE!

got car back last night, and the problem has almost gone! it revs to 3 grand now, im thinking maybe the launch control button has been played with, going to reset the launch control back to 4k and see how we go, im still spitting tps sensor, and after cleaning iacv valve got that code too?

Make sure your TPS is calibrated properly. You might need to change the TPS

o/

Firstly, you should diagnose the fault instead of trying this and that to see if fixes the problem. A process of allimination is well and good, but, this shouldnt involve fixing problems that dont exist or that others have had(common faults excepted, ofc). If you want to elliminate the posibility of a fault in a particular system, you should isolate and test that system. ie: dont replace a fuel pump to see if fuel preasure was the problem, isolate and test the fuel system.

With EFI cars your first step toward solving the problem should always be, after ensuring the car has it's vital fluids and is in otherwise good order, fault code extraction. Be it via the check engine light flashes method or with a scan tool. Beware: these codes can sometimes be deceptive for a few reasons. i)Some systems will display a fault that the computer thinks is the problem based on the information given to it by sensors, but never the less, the faults displayed in this step should be taken into consideration highly, even if it is with a grain of salt. ii) The fault code/s displayed at this time may related to another or previous problem with the EFI system. If you get a code indicating a fault with , say, a TPS; you should then test the TPS using the correct method. side note on TPS: In my experience, TPS get calibrated at instalation and usually dont need recalibration unless removed and most TPS testing can be done without removal.
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So, where should you go from here?

Clear the fault codes and run the engine to see if the code is old or is a soft/hard code.

Isolated the system at fault(pos. the ignition system in your case) by eliminating other systems. Ask the questions; is this system doing what it should be doing? Am i getting what i need here from this system and/or component? The first step in this process is to establish if the fault is common to all cylinders or just one. Doing this first will eliminate components/faults either common or uncommon to individual cylinders. For example: You may want to reproduce the fault by increasing engine rpm to a point where the fault presents itself then remove, for a few seconds and one at a time, the injector plugs and, between you and a friend(get him to not have his head under-bonnet with you), determine whether the fault is confined to one cylinder or common to all. If removing one of the plugs dosnt make as much difference as removing the others or makes no difference at all; it's likely to be something wrong with a component specific to that cylinder eg: a spark plug, HT lead, injector and not a coil, coil lead, fuel pump or even a TPS.

Go from there.

Let me know how you go, but, plz post the year, model and engine details of your car and any engine mods it may have. Also, does the fault get worse as engine load is increased(higher gear)?

Gord

hi thanks for the informative post!.

however problem was diagnosed early today, turns out.... here we go...... someone had played with my little red button... (hondata button) they reset my launch control, and somehow managed to get in further and set up a shift light.

but im glad it all happened. cleaned TB, replaced coolant, did somethings i should have done reguardless!!

it would have happened the night of the cruise, as people were looking in my car, guessing some hooligan thought it was cool to play with my shit.

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Originally Posted by Alexplicit

it would have happened the night of the cruise, as people were looking in my car, guessing some hooligan thought it was cool to play with my shit.

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Lol can't believe they did this to you dude I'm hoping my issue is as simple coz ATM a new ECU is being made up for me -.- I actually haven't checked my hondata unit for a button (s200) is the model

same as mine :) good luck !! hope u get it sorted!

Where did u find this red button bro ?

its the buttom that is for the s200, so u can set your launch control, full throttle shift, rpm limit and shift light.

type into google hondata s200 button or something

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Originally Posted by Alexplicit

its the buttom that is for the s200, so u can set your launch control, full throttle shift, rpm limit and shift light.

type into google hondata s200 button or something

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Button on the bottom
Of s200 lol this sound crazy man was this button custom made?

Yeh my car done this bout a month ago so I just put the standard computer back in I think it's a safe mode for the Honda unit due to mine was in the garage the hole time.. Also there is no button on my s200 all done by computer

the button is simply an option to change limits (rev limit , vtec point, launch control ect) on the fly

Rev hunt?

Or Rex Hunt??

Am I right?????

Eh heeeeee

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Originally Posted by Vvvtec

Rev hunt?

Or Rex Hunt??

Am I right?????

Eh heeeeee

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http://www.ozhonda.com/forum/member.php?30053-Vvvtec