Help Me With This Misfire...

[Konrad]

http://www.skylinesaustralia.com/forums/in...howtopic=129882

any ideas??

[The Dan]

Faulty wiring connection maybe?

Might be time to start swapping parts as you look like you have covered everything else. Not my idea of the best way to solve the problem but sometimes it's the only way you'll ever find it.

What work has been done to the car?.....I mean every single thing that has been done, right down to the wiper blades being changed.

[R33S2]

Intermittant faults really get my back up!

[MajorSick]

First things first. Injector cleaner from a bottle is useless.

You should get your computer checked. It costs $120 * I belive * to have your computer sent away and

checked to make sure it's all working correctly. After having done all you have that is the only logical

outcome. Find out first how much it is to have tested and cross your fingers thats your problem becouse you can get a new one * Or an after market good one * for a fairly good price *

[T04GTR]

ref my responce

[Konrad]

thanks guys... replied in other post

[T04GTR]

new reply

[R334door]

http://www.skylinesaustralia.com/forums/in...howtopic=129882

any ideas??

sounds like a blown head gasket.check compression on that cylinder with the plug that looked different then compare with another cylinder,if its down alot then there you go.

Edited August 12, 2006 by R334door

[53XYN]

hook up a mulitimeter and check for ecu fault codes, if any if not then check your coil pack supply IR the power ground and ignite supply on the car and the coil , if not then check the cable connections on your fuel pump , also check your turbo oil lines etc.. also your vaccum hoses around your boost lines fuel pressure regulator lines etc.. if possible unplug one of the fuel lines while on dyno check to see if it supplys enough fuel.. maybe your stock ecu is hitting boost cut or overriding the fuel pressure .. mine did the same my faults where

- Walbro fuel pump (stuffed within a week)

-ECU boost cut( turbosmart FCD fixed it)

-coil number 4 didnt have any power going into it

after all that it went perfectly smooth

mine was a s2 hope tis info helps

[Konrad]

Thanks for the great responses guys i'm taking it all on board...

Shes still no better after checking the coils plugs connectors etc..

I dont have a multimeter- will go buy one...

I dont think its hitting boost cut, as it is a constant misfire - from idle (ie: not under boost). For the record nothing recent was done to the car exept.....the addition of a walbro fuel pump....hmmmmmmz

I went back to the stock plumback bov, didn't help either...

I just hope i dont do too much damage driving it around like this, it runs pretty rough from 2-3000rpm thats gootta be bad for the internals right?

[Konrad]

pics of my sparkplugs in the other thread if anyones interested

[53XYN]

dont think you should drive it for prolonged periods .. , your turbo exhust wheel hasnt fallen off has it ? apprently if the exhaust wheels drop off they idle pretty back low end ..

[Konrad]

got no choice mate- have to drive to work this week i'm up in buderim (driving from logan), next week its redcilffe- worst week eva to have this happen lol

And pretty sure the turbos fine, it makes full boost no problem.

[R334door]

got no choice mate- have to drive to work this week i'm up in buderim (driving from logan), next week its redcilffe- worst week eva to have this happen lol

And pretty sure the turbos fine, it makes full boost no problem.

hey im im maroochy if you want me to have a look at it to help one arvo if your up this way after work just pm me.

[12DFY]

Just a problem I had in the past. I had a similar misfire at low RPM but when it was revved the speed of the engine hid the misfire. It was still there but it was not audible. I ended up doing a compression test and found one of my cylinders was only about half the others (SH#T). After further investigation was found that no4 piston land(between rings) had cracked. And when i pulled out the piston part of the land fell out with it??

Hope it isnt this bad for you but definately worth the compression test. Compression testing will rule out valves, head gasket and bottom end! (worth doing for piece of mind).

[Konrad]

hey im im maroochy if you want me to have a look at it to help one arvo if your up this way after work just pm me.

Hey mate,

I'm working 12-8pm shifts i'm afraid, but if you have a free morning, or dont mind having a look in the evening i would be happy to drop by to see if we can come up with anything...

I'm staying down in moorochydore but will have to drive up to buderim each day.

Was planning to get a compression check, diagnosis etc.. done at a mechanic in mooroochydore, would you have any recommendations?

[Konrad]

Just a problem I had in the past. I had a similar misfire at low RPM but when it was revved the speed of the engine hid the misfire. It was still there but it was not audible. I ended up doing a compression test and found one of my cylinders was only about half the others (SH#T). After further investigation was found that no4 piston land(between rings) had cracked. And when i pulled out the piston part of the land fell out with it??

Hope it isnt this bad for you but definately worth the compression test. Compression testing will rule out valves, head gasket and bottom end! (worth doing for piece of mind).

Damn sounds alot like my problems going to get a comp check done ASAP..

[12DFY]

Damn sounds alot like my problems going to get a comp check done ASAP..

And on the other end of the scale it could be as simple as a stuck valve etc. But I am on the Gold coast, if you were down this way I would happily compression test for you. When the previous problem I stated occured it was not like a complete misfire, but was definately audible at cruising speed and idle.. Car did not feel down on power too much on full noise???

[Konrad]

Well its a definate shudder at idle, and sounds like a wrx, the worst is when you put a bit of load on the motor with some throttle (say going up a hill or taking off from the lights at slow speed) the sound changes to more of a kombi sound lol it shudders from 2000-3000rpm , then is less noticable (but still definatley there, jsut the higher rpm masks it i think). The car will build full boost but doesn't rev out cleanly like it should.

Lifting off throttle the car runs down completley normal - no shudder, hesitation, knocking noises etc..

Guess i'll know next week.

Thanks for the replys guys

[Konrad]

Ok so i disconnected each coil to narrow it down to a cylinder that was the problem, its no.1.

First thing i did was pull the sparkplug out, looks a bit black, and has that shiney coat i mentioned earlier? Could be fuel??? but had no strong fuel smell to it...

Ran a compression test - 150psi on that cylinder (didn't have time to do the others)

Put in a copper plug, didn't fix it, took out the splitfire coil and replaced it with my standard one, didn't fix it.

So at this stage i'm assuming it has to be a wiring fault to the no.1 coil.