R33 Missfiring?

[GTR_STEALTH]

Ok pplz i've got a few ideas on what it could be but not too sure...

The car:

R33 S1 Auto Skyline with...

3inch zorst cat back.

The solenoid 'bypass/earth' mod

The problem:

Slight one off misfire usually at idle.

I noticed it started after i put the exhaust on. I would be sitting at the lights when all of a sudden it would get just a one off missfire. Its completely random...i might get a missfire at one set of lights then maybe 10min later at another set i'll get another missfire.Doesnt sound like its gonna stall or anything but yeah....

Extra info:

-Now i havent reset the ecu yet after i put the exhaust...could this be a prob? Will try this today in the avo but i doubt it very much.

-When i bought it a few weeks ago from a dealer pretty much everything was serviced....fuel filter, oil, air filter, etc except spark plugs and lead...could this be it?

Any help much appreciated....

Edited November 2, 2005 by R33_STEALTH

[GTR_STEALTH]

Ok just read another thread with similar probs as mine although mine doesnt do it regularly...yet!

Yeah mine is completely random.

the link

http://www.skylinesaustralia.com/forums/in...showtopic=92885

[sl33py]

Exactly the same car and situation here (even down to owning the car a coupla weeks ). Except the aftermarket exhaust on my car was there when I got it and I don't have the solenoid 'bypass/earth' mod.

My miss is more often, about once every 15-20 seconds. I'm about to try running nulon complete fuel system cleaner or wins injector cleaner through a complete tankful and see what happens. Mate who looked at my car also asked if I noticed it during acceleration. I don't know because there's 5 other cylinders and it's not even that obvious during idle (except I hate the sudden chug/gap in exhaust note when it DOES miss), so not like I'm gonna feel it.

My mate also says it's a bit of a ba5tard to find problems like this, cos it could be anywhere. Try some injector cleaner like I am and we'll see how we go. Failing that, I'm gonna show some local 'line owners, see what they think and failing that take it to a shop and possibly waste a hundred or so bucks...

[sl33py]

Lol... said like Ghostbusters 'don't cross laser streams' while they're zapping Slimer: 'don't cross threads!' jk we'll figure it out mate. it's a shame to have niggles like this on a car that's so perfect in every other way, so i'm sure someone knows how to fix it. Try the fuel cleaner first, getting mine this evening after work. And don't forget u need to run a complete tank full of it for it to do it's job, so don't worry if it doesn't fix it til u've done ~400kms. Then have another listen/feel of the engine on both cold start and after a semi spirited drive to see if any difference.

[GTR_STEALTH]

Yeah dude same deal! LoL

At least i dont feel so alone now! HaHa

If it was a commodore then i'd have narrowed it down in 10min!!! ...still learning about these.

Im strongly leaning towards an electrical prob....more than likely coil pack, leads, spark plug...although the 'randomness' has got me scratching my head which is why im also thinking maybe ecu to be reset...???

[hbs2jh]

hey man.. it's likely to be spark plug or the coil or the lead..

get check up.. i'm pretty sure one of dis three..

u running at 98 octane righT?

[GTR_STEALTH]

Yeah running 98 octane...

Will check contacts on the coils first...

[sl33py]

Yeah 98 octane here too. The dealer I just bought mine from said they checked the coilpacks cos when I first test drove it, it had the cutting in/out problem between 4-5000rpm which lots of ppl talk about. They replaced the spark plugs from "Iridiums which were strangely gapped" (sic) to something more suitable, which fixed that problem on the next test drive. I'm not so handy with electronics to check the coilpacks myself. I read somewhere on here about slight cracks in the leads or coilpacks themselves (i think?) causing real problems, might be another avenue to follow as opposed to just the connections themselves. I'll look back into that if the injector cleaner doesn't do the trick (fingers crossed).

[hbs2jh]

i have exact problem with me atm

i ordered coil pack to come.. i have already cleaned my air flow meter and filter. also tryed injector cleaner.. and exchange all 6 spark plug to NGK iridium.. i also found that i have leak in my exhaust system.

between turbo and manifold. i need to change gasket as well..

i u guys know if i fix it..

which one it was..

most likely to be coil i fink..

[GTR_STEALTH]

UPDATE 8-11-05

Firstly i tried to reset the ecu but it didnt seem to do anything.

Then i put the boost back to standard as apposed to having it constat 7psi via earthing the solenoid....Hey presto!

I think wat was happening was the computer didnt seem to like the mod so it wanted to 'complain' lol....

So yeah...anyways...

Problem solved! :lol: For me anyways...

[sl33py]

Glad u fixed urs. Stock boost here. Half a tank of injector cleaner used and no real change.

Too busy to really do anything else for it yet.