Anyone with a cold start misfire...

[majid]

Was battling with the problem for a while. Always was cylinder 2 misfire at cold start. Once the idle dropped to normal ran smooth as could be. Did the typical swap plugs and coils and so on. Still had the same problem. Finally bought the injector and got a chance to put it in. Does not look like it was the injector at all. There was so much carbon build up around the intake valves it was insane. Of course cylinder 2 was the worst. We did still change the injector just in case. Runs so great now and not so much as a hiccup at start up So for those of you with this problem, I hope this helps, and i guess the intake is coming off either way

[JLT]

interesting...


Modified by JLT at 10:27 AM 1-15-2009

[jpimp61]

how many miles on ur engine?

[JLT]

im at 35,000 and my cyl 4 is cold start misfiring even with new exhaust valve lashes (tsb) and new plugs and coilpacks. dealer suspects heavy intake valve deposits. they will let me know today...

[majid]

Quote, originally posted by jpimp61 »

how many miles on ur engine?

128,500

Quote, originally posted by JLT »

im at 35,000 and my cyl 4 is cold start misfiring even with new exhaust valve lashes (tsb) and new plugs and coilpacks. dealer suspects heavy intake valve deposits. they will let me know today...

I'd put money on it at this point
I did forget to mention that the exhaust valve tsb was done on my car when we were trying to figure this out. Did all of them just in case. Had to do the cam so we did them at that point


Modified by majid at 11:18 AM 1-15-2009

[M0riarty]

I am battling the same cold start misfires, only mine is on cylinder 1. They used to be more sporadic, but now it seems every other or 3rd cold start causes it. I am at 43K now, car has done it since about 30K.

Only thing I have tried so far is swapping coil packs - no difference. Plugs were replaced at 20K with 1 step colder plugs. Finally bringing it to the dealer next week to have them look at it.

[Murder'd]

Quote, originally posted by M0riarty »

... with 1 step colder plugs.

I can see this as being your issue. Swap plugs back to stock and see if your cold start issue goes away.

[M0riarty]

Quote, originally posted by Murder’d »

I can see this as being your issue. Swap plugs back to stock and see if your cold start issue goes away.

Car is chipped though - it was my understanding that the car should run better on 1 step colder plugs if chipped/modded. Is this not the case?

I'll try the stock plugs.

[majid]

Quote, originally posted by M0riarty »

Car is chipped though - it was my understanding that the car should run better on 1 step colder plugs if chipped/modded. Is this not the case? I'll try the stock plugs.

Don't hold your breath though. I tried the same thing

[JLT]

my dealer let me know today that when they checked my intake manifold it was nasty and they cleaned it out with throttle body cleaner and some tool. they cleaned up the valves and its supposedly cold starting fine now. they are going to let it sit over night and crank her in the morning and watch for misfires. Hopefully, we'll be in the clear and I can have my car back. Believe this - my car has been out of service for over 20 days bc of parts shortages etc.

[veedubtek]

Quote, originally posted by majid »

Was battling with the problem for a while. Always was cylinder 2 misfire at cold start. Once the idle dropped to normal ran smooth as could be. Did the typical swap plugs and coils and so on. Still had the same problem. Finally bought the injector and got a chance to put it in. Does not look like it was the injector at all. There was so much carbon build up around the intake valves it was insane. Of course cylinder 2 was the worst. We did still change the injector just in case. Runs so great now and not so much as a hiccup at start up So for those of you with this problem, I hope this helps, and i guess the intake is coming off either way

I'm not sold it was the intake over the injector, but it's near impossible to say for sure. Even at 20K miles, my intake ports looked like complete ass.

I'll say this...if you're gonna venture in there to clean your intake ports, hit the dodge dealer up for a can or 3 of their combustion chamber cleaner from the late 90's ram intake manifold campaign...that **** worked great on both our cars There was quite a substantial difference from cleaning cylinders 1&2 compared to 3&4 where that stuff had a chance to soak in a bit.

[majid]

You forgot to mention my injector looked better than yours. Even with 100,000 more miles on it lol

[JLT]

http://forums.vwvortex.com/zerothread?id=4209615

Modified by JLT at 6:40 PM 1-19-2009

[majid]

Quote, originally posted by JLT »

http://forums.vwvortex.com/zer...d=739

Was this what you meant to post?
http://forums.vwvortex.com/zerothread?id=4209615

[JLT]

yea lol oops

[JLT]

they said my intake manifold was narsty and cleaned it thoroughly, they also did the TSB. IDK what fixed it but it seems fixed, no codes on the vag com. tomorrow is going to be an unusually cold day for here so I'll crank her over in the am and see how she idles etc.

[JLT]

OK - so my car is misfiring again looks like the dealer didnt fix my shizurnum.

[majid]

Guess that means injector

[JLT]

Yes, I believe that it has to be the injector, but I cannot understand what exactly is wrong with the injector that would cause it to do this. Perhaps it is a leaking injector, while the car is off and sits over night, it leaks fuel into the cylinder. at Start up, there is too much fuel in the chamber and it misfires....what do you think?

[majid]

Quote, originally posted by JLT »

Yes, I believe that it has to be the injector, but I cannot understand what exactly is wrong with the injector that would cause it to do this. Perhaps it is a leaking injector, while the car is off and sits over night, it leaks fuel into the cylinder. at Start up, there is too much fuel in the chamber and it misfires....what do you think?

The carbon build up caused the leaking, so yes you are correct

[JLT]

my contacts at APR concur and gave the same response, however, I can't confirm til it goes back in the shop...AGAIN.

[JLT]

got car back. the dealer did two things. they removed the injector and installed a new one, and they removed the intake manifold, soaked the valves in cleaner, and then wire brushed them clean. they claim to have removed tons of carbon deposits. idk what to believe, but we'll see how it starts tomorrow its going to be around 39 here so we shall see.

[rippie74]

Quote, originally posted by M0riarty »

Car is chipped though - it was my understanding that the car should run better on 1 step colder plugs if chipped/modded. Is this not the case? I'll try the stock plugs.

I'm running factory plugs & I'm ok (13,000 miles on a Stage II engine)

[GolfRS]

Did some VAG COM logging today, and saw i get misfires at idle, when rpms are at the lowest.If i turn on the A/C and the rpms bump up a bit, the car idles as smooth as butter, which leads me to believe its probably
a bad lifter.A sticky valve would also do the same, but the thing is i don't see any fluctuations in my vaccum gauge....

I'm thinking of doing all of my lifters but thats gonna cost a lot.
Just figured as long as i'm taking the cover off, i might as well replace them all (and not just the exhaust ones).Is that gonna be a waste of money ??

[JLT]

that sounds to me like a tuning issue. of course, check the things we've checked. i am about to go out to my car and start her up. fingers crossed I don't get a CEL and that lame unsteady idle.

[GolfRS]

Quote, originally posted by JLT »

that sounds to me like a tuning issue. of course, check the things we've checked. i am about to go out to my car and start her up. fingers crossed I don't get a CEL and that lame unsteady idle.

That could be the case, but it only happens on cylinder 3, and AFAIK there is yet to be
any "individual cylinder tuning.." ...LOL

My thoughts are on a sticky valve or lifter, that just can't move properly at low rpms.
Once the rpms rise, it works properly once again,
Funny thing is i have ZERO misfires at WOT...

[JLT]

Pm'd you

[JLT]

well I would have told you on the phone but I'd swap injectors first, then I'd have the intake manifold manually scrubbed. Then I'd clean intake valves, and if that does not fix, I'd do exhaust lashes (the tsb).

[rracerguy717]

Quote, originally posted by GolfRS »

That could be the case, but it only happens on cylinder 3, and AFAIK there is yet to be any "individual cylinder tuning.." ...LOL My thoughts are on a sticky valve or lifter, that just can't move properly at low rpms. Once the rpms rise, it works properly once again, Funny thing is i have ZERO misfires at WOT...

Your #3 injector is bad IMO , but you like doing things the hard / costly way .

The reason Why the mis-fire goes away when you put the A/C on is it puts a load on the motor which makes the injector m.s. rise giving more fuel= no misfire .

The mis-firing is because the injector is not allowing enough fuel at that very low rpm making it run a little lean= misfire . Bob.G

[GolfRS]

I've been having these misfires since i got my car, although not in such frequency
My injectors have about 20000 miles on them.I had them changed to S3 ones when i put the S3 kit on.I highly doubt it's the injector....

[rracerguy717]

Quote, originally posted by GolfRS »

I've been having these misfires since i got my car, although not in such frequency My injectors have about 20000 miles on them.I had them changed to S3 ones when i put the S3 kit on.I highly doubt it's the injector....

These DI injectors have very tight tolerances and very problematic that's why VW is getting away from them in the new TSI and you will see the next DI motors will end up with a pizo injectors IMO its just the cost of these to manufacture is still high.

I put a set of 4 RS-4 injectors a few months ago and they where BRAND NEW and I was getting slight mis-fire in cyl 1 so I changed that 1 again and I have had zero mis-fires ( cold or light throttle or @ WOT ) ever since . Bob.G

new doesn't always = good

Modified by rracerguy717 at 1:05 PM 1-24-2009

[GolfRS]

Well i still don't think its the injector..

Truth is there are many things that could be wrong, one of them also being the rings in my motor (AXX).

From the cost point of view, removing the manifold and replacing ONE injector is gonna cost me more than doing ALL of the lifters, just because i'm also doing the cams....

Car runs awesome at WOT though.....At least i've got that...

[JLT]

It is your fuel injector. They are not all winners bro. Swap the fuel injectors.

[GolfRS]

Quote, originally posted by JLT »

It is your fuel injector. They are not all winners bro. Swap the fuel injectors.

Well resurrecting this thread....

I did the injector swap and cleaned my valves...

What a PITA...(pics soon)

Good thing is i got rid of the banjo bolt and went to a tube design

Bad part is.....NOTHING CHANGED !!! AAAAAAaaaaAAAAAA...

I gona kill this f...n car......Now i only hope its not the rings.....

[iGen3]

part number(s) for conversion from banjo bolt to non-banjo bolt? Thanks.