JDM B18C struggling and little backfire

[zropts]

Hi,

My car with B18C is currently stuggling (kinda choking splut splut splut etc. noise from the engine & exhaust on cold start up) when I change gears from 2nd to third, or third to fourth etc before 3000rpms and struggles 3-4 times more than before. After 3000-4000rpms, car seems to pick up again. Sounds kinda like a bad air/fuel mixture, bad tuned car or car with harder cams. This is usually a smooth gear change & a smooth ride but now a disaster. You can also hear the exhaust choking a tiny bit (not running smooth like before) and the whole car wobbles a little when doing the gear changes. Idle is smooth and stays constant and NOT reving all over the place. Well some mechanics has said that if its electrical, the car wont start (not sure if its electrical).

VTEC is ok. No CEL values.

Since this, I have changed:


Spark Plugs - bought new spark plugs - no difference
Spark Leads - tested with a mates NGK spark leads - no difference
Changed to Walbro Fuel Pump - no difference
Change fuel tank - air gunned fuel line from fuel tank to fuel filter to clean rust particles- no difference
Change to new Oil Filter - no difference
inspected and tested Distributor - tested to OEM manual specs (ICM etc) - no difference
New Toda Timing belt set correct - timing set when engine was out. - no deifference
Change New Fuel Filter - no difference
Change/flush Honda FEO Motor oil - no difference


All fuses checked (underdash & under bonnet) - All working order

What else could be the problem?

O2 Sensor?
Coolant Sensor?
Clogged up injectors?
Fuel Pressue regulator faulty?
TPS?
FITV?

[VTec1987]

post up a video of the engine on idle.

could be anything, video of the car running would help

[SiReal]

sure its not a blocked exhaust system? CAT might be screwed up. Swap it with a mate and test that.?

[zropts]

I got JDM Cat. If the cat is stuffed up, what am I looking for? Will change and let you know.

[Bludger]

clogged injectors is a possibility.

very hard to diagnose, vid is best :thumbsup:

[MM89]

this is the exact same situation i'm in at the moment..the car is quite thirsty as well.

happened to me after i cleaned IACV, adjusted TPS (shouldn't have done this if i knew s300 could control it.....)

also cold starts are wierd...revs up to 2,000rpm immediately and within 10 seconds returns to a 1100rpm idle until it warms up.
idle can be quite inconsistent and after a period of start and stop driving, the idle begins to rise a little above 1000rpm upon coming to a full top.
it may even hunt around for a little bit. i'm assuming i may have stuffed the IACV?

[zropts]

What I'll be doing is check my CAT, buying TPS & get RC 240CC fuel injectors and diagnose this problem one by one to find the real problem. Really doing my head in atm. Wil let you know once I find the problem.

[Bludger]

bad fuel is another.


actually can you please detail what you've done.....

not just short list.

[Alexplicit]

tried swearing at it? kicking the tyre? giving it evils? "puttin the staunch on it"?

did u do any mods to the car before it happened? touch anythin under the bonnet around the same time it started doing it?

[Tai]

Was anything done to the car prior to this happening?

[zropts]

Nothing was done. But I did find out the fuel tank was corroded "after" this was happening thus having to change the fuel tank, fuel pump & bracket and replacing the clogged fuel filter. Would it be possible for the tiny rust particles to travel past the fuel filter and into the injectors?

[Bludger]

I don't know, its a possibility.

maybe something you already have ruled out but over looked.

[zropts]

tried swearing at it? kicking the tyre? giving it evils? "puttin the staunch on it"?

did u do any mods to the car before it happened? touch anythin under the bonnet around the same time it started doing it?

I did launch it hard a couple of times the night before this started to happen. :)

[zropts]

I don't know, its a possibility.

maybe something you already have ruled out but over looked.

Yeah possibility of the distributer that I overlooked...

[Bludger]

I'll tell you about my experiences.

Even when you try your leads on another car and it works properly, it doesn't mean it works on your car. (eg. b16a it worked, b18c, it didn't, don't ask how, don't know, just the way it is.)

spark pkugs look fine? change them anyway.....

obd0 resistor box for the injectors. wires were loose. doesn't apply to you cos you're b18cr.

bad fuel, good running when full tank, bad when near empty.

does it sound like running on 3 cylinders or is just choking?

[zropts]

I changed to new copper spark plugs already at the start of problem. Car doesn't sound as rough as its running on 3 cylinders... sounds a little choking

[Bludger]

recheck the whole fuel system from tank to injectors.

thats what i would do from the information I have.

don't overlook anything.

[zropts]

a full engine coolant flush was also undertaken a few days before this started to happen. Now coolant is escaping from the cap. I'm sure the cap is like 2-3 years old. Cap is 1.1. Could it also be the coolant temperture or ecu coolant plug gone? Or could it be that coolant is escaping and the ecu can't read the right tempertures thus causing the car/engine to jerk?

[Bludger]

highly unlikely

[zropts]

thanks, that 1 less to worry about.

[MRK20CRX]

hmm i'm experiencing the same kind of thing, there's this sputtering between 2k and 4k rpm, it's guzzling a lot of fuel than before, i changed my spark plugs and there was a lot of carbon build up on cyl 2 and 3, but 1 and 4 looked ok

[dvsx]

this happened to me too, turned out my spark plugs were wet from washing the bay...

[Tai]

Check it any grounding points have become loose.

it may not struggle when u start up but if you are driving and shifting it might bounce around and cause engine to struggle due to engine movement.

[zropts]

Check it any grounding points have become loose.

it may not struggle when u start up but if you are driving and shifting it might bounce around and cause engine to struggle due to engine movement.

Ground points... hmmm... can be, true my car doesnt struggle when first starting car but runs a tiny rough like its choking...

if what you'e saying is correct :) this can save alot of $$$ diagnosing problem... hope it is! Checked Honda-tech and there are absolute NO ANSWERS to problems like these (for all model types) lol!

[gambate]

also cold starts are wierd...revs up to 2,000rpm immediately and within 10 seconds returns to a 1100rpm idle until it warms up.
idle can be quite inconsistent and after a period of start and stop driving, the idle begins to rise a little above 1000rpm upon coming to a full top.
it may even hunt around for a little bit. i'm assuming i may have stuffed the IACV?

try reduce the IAC duty cycle in SManager under: parameter->idle
or reduce the water temp compensation under: parameter-> fuel compensation
--hondata dump too much fuel for cold start in my case if leave this unadjusted from "stock-itr" map.
maybe uncheck "closed loop operation" if you are using stock O2 sensor setup.
adjusting the above works for me...

[sangyz]

I did launch it hard a couple of times the night before this started to happen. :)

If this happened I'd say change your tps to a brand new one. This happened to my jdm b18c and it doesn't through a cel code.

[zropts]

Since TPS is cheapest replacement part of the others, might buy a new one and test it out.

[zropts]

Still yet to test TPS tonight, and replace injectors when they come in. In the meanwhile, mechanic stated that my cylinder #2 contains a little oil on spark plugs and piston #2 is possibly not working 100% therefore the jerking at low rpms but at mid range to high rpms, its all good.

Is there any internal mechanical problems I should be worried about?

[EG30]

no microcracks on your dizzy caps or dizzy rotor by any chance?

[p3akin]

change th timing belt, dizzy and/or tighten up the timing belt.. timing belt could be loose

[Bludger]

change th timing belt, dizzy and/or tighten up the timing belt.. timing belt could be looseI don't see how that relates to his problem........

[zropts]

Tested the plug wires (green and red) on TPS when plugged in and turned the ignition to second click. No voltage reading. Can this be the TPS is gone?

[zropts]

no microcracks on your dizzy caps or dizzy rotor by any chance?

No cracks and cleaned out rotor and cap.

[p3akin]

I don't see how that relates to his problem........

exactly same thing happened to me.. the timing belt ended up falling off stuffing my internals...

[Lukey]

exactly same thing happened to me.. the timing belt ended up falling off stuffing my internals...

if you would have read the first post you would have seen his replaced it?

[Bludger]

if your timing belt falls off then your car won't run at all.

It won't get the chance to run roughly.

[sangyz]

Tested the plug wires (green and red) on TPS when plugged in and turned the ignition to second click. No voltage reading. Can this be the TPS is gone?

Mist likely I'm pretty sure there's meant to be a voltage reading that's normally how you adjust it according to the voltage reading so maybe it's gone?

[p3akin]

if you would have read the first post you would have seen his replaced it?

i said tighten not replace


if your timing belt falls off then your car won't run at all.

It won't get the chance to run roughly.

i didnt say his fell off.. i sed mine was loose than fell off..

i cop backfire now than than driving normally and one day it popped off...

[Lukey]

i said tighten not replace


you said to replace before tighten.

[p3akin]

and/or is what i sed but im not going to argue.. just trying to help a fellow ozhondian out

[Bludger]

don't bother with lukey, he's a ****ed up kid.

[zropts]

Mist likely I'm pretty sure there's meant to be a voltage reading that's normally how you adjust it according to the voltage reading so maybe it's gone?

Maybe...! I got one coming in soon which I will test and adjust first. Let you know how this goes.

[zropts]

Check it any grounding points have become loose.

it may not struggle when u start up but if you are driving and shifting it might bounce around and cause engine to struggle due to engine movement.

Ground points checked and are not loose.

[Lukey]

don't bother with lukey, he's a ****ed up kid.

oh hai thar bau

[Bludger]

where's my towbar?

lol

[Lukey]

where's my towbar?

lol

you still want it? we never got around to organising anything haha.

[Bludger]

I'm worried it won't fit under the update rear bar.

can you take pics and enmail me please.

[zropts]

New TPS fitted & adjusted. Problem still there!

[sangyz]

how did you go about finding out if the cylinder is gone?? are you blowing any kind of smoke?

[zropts]

No smoke is blowing out... sounds like I'm running 3 cylinders... Now I have to wait for the new distributor & injectors to get here and see what happens after installing this.

[sangyz]

have you tried a compression test?

[zropts]

cylinders tested and got readings above 220.

[sangyz]

hrmm so much tested yet still cant find a problem. also when you did the new tps did you get a voltage reading this time? if not maybe could be faulty wiring?

i guess wait until you get your injectors and see if they are blocked or not

also with your distributor cap was it changed or anything done to it before this happened? maybe it wasnt adjusted properly.

dunno if this has been said or not. but have you checked all your vacuum hoses for splits??

[zropts]

Yes TPS had voltage readings now and have been set. I didn't know I had VTIR looms on the car thus the dizzy was my old VTIR dizzy that was put on the B18C and the dizzy now has travelled roughly 230,000kms.

Also will be putting ITR looms in with a new dizzy or old one (if I can find one) and see how that turns out.

[sangyz]

Hrmm dunno if that will help but its worth a try. if it was running okay with the vti-r looms before. i dont think the loom will do anything has to be something else that is faulty

[zropts]

the ITR loom won't do anything I'm sure, but at least the plugs on the looms fit the type r dizzy. I'll give it a go.

[Bludger]

this is doing my head in

lol

[sangyz]

lol sure is .. cant think of anything else lol

[zropts]

its doing your head in? **** lol... gotta keep positive and options open I guess... at the end of this, hopefully I can write up what symptoms caused what and what steps to take in order of replacement.

There is only limited problems that have been solved online and there are problems that people have not faced before or still an issue... this leaves with very minimal information on diagonosing a situation like this online.

As for me, I will be replacing part by part and find the real culprit of this problem.

[sangyz]

good work man. will be good to find out what it is. also have you considered your ecu being faulty?

[zropts]

Yes I have, but this would be the last thing I check as I'm running OBD1 ecu and will get a ITR OBDII ecu with harness to fit to diagonose.

After all items tested and fitted, hopefully it all runs well again.

[Bludger]

its doing your head in? **** lol... gotta keep positive and options open I guess... at the end of this, hopefully I can write up what symptoms caused what and what steps to take in order of replacement.

There is only limited problems that have been solved online and there are problems that people have not faced before or still an issue... this leaves with very minimal information on diagonosing a situation like this online.

As for me, I will be replacing part by part and find the real culprit of this problem.its always going to be the last component you replace.

but after that, you have a much newer car

LOL

[zropts]

Agree! This will save future time for faulty parts. Might as well fix everything at the same time and save the headaches for 5-10years!

[zropts]

OK OK OK! Problem solved at freakn last!

Firstly the car was struggling as stated in first thread. I checked all vacuum hoses & ground wires and then changed the below:

New Iradium Spark Plugs
New Spark Leads
Check distributor (coil & cap)
New Walbro HP Fuel Pump
2nd hand Fuel Tank - only because old one was corroded with particles flying everywhere in the tank
New Fuel Filter
New Throttle Position Sensor (TPS) - adjusted at WOT 4.14V & CT at 0.53V
Cleaned Throttle Body
Cleaned IACV
New Engine Oil
and then.... my RC 240CC injectors arrived today with clips (mechanics charge $200-$250 for my old injectors cleaned - get f*) so I thought I buy these new for around $360 inc. clips (at least I know they're new), put them on as in the teg manual (easy as - 5 bolts and 2 hoses) and reset ecu... took it for a drive, and it works like NORMAL again.... damns! If only I knew, I would have done it first...

haha, Bludger, it is always the last thing you frekn fix... and yeah IT IS!!! lol - now put that head to rest....

Also the above list, I would do them in order as they are the cheapest parts to fix until you reach to buy new injectors, distributor, ECU etc.

All I can say that if its not electrical (as you can see I have checked all electrical components) then it can be the fuel components... after you have checked and performed the above, I would move into testing fuel pressure then swap ECU.

Thanks all for your suggestions and help.

CONCLUSION: CLOGGED UP INJECTORS!!!!

[Bludger]

did the symptoms just happen when cold or at all temperatures?

[Bludger]

I'm so glad the issue is resolved

[Bludger]

LOL, check post #5

[Tai]

Fail !

[zropts]

haha... well it happens cold and warm... doesnt matter!

[DC2-PWR]

LOL, check post #5


Bludger deserves lots of points!

Can't wait to change my injectors.

[dc2r-0636]

bump, zropts hows the car going with the new injectors?

[zropts]

Yeah working all fine and no problems at all after replacement. I recommend it.

[dc2r-0636]

sweet, how many kilometers when it started doing this ? coz my car is sitting on 101,000kms and isnt this too early for injectors to stuff up like this ?