cold start / idle misfire below 1k rpm

[socalhatch]

Hello all, so as the title says i have been chasing this issue at idle / cold start for about a month or so now. Issue started up out of no were with no hardware changes. Randomly got a CEL one day and checked it random multiple cylinder misfire all 4 cylinders 1100rpm time stamp shows cold start. Ok Carbon build up? did a walnut blast the carbon was pretty bad at 55k miles so i thought this would fix the issues, but it did not. The car is stage 2 IE full bolt on minus intercooler piping. Rs7 plugs, oem coil packs. Only thing i can think of is the injectors going out or massive carbon built up on the tips, when i did the walnut blast i did not take the injectors out to look at them.. Wich i am kinda of regreting now.. Any help much appreciated.

 

[Diggs24]

Unhook evap purge line from pcv and plug it.

 

[socalhatch]

This wont cause a build up of evap pressure?

 

[Diggs24]

https://www.golfmk7.com/forums/index.php?threads/evap-witch-hunt.368834/

 

[scrllock]

prob direct injectors

 

[socalhatch]

I'll give it a try, not having the same codes pop up as the guy in the link. but its worth a shot before spending the $ on new injectors.

 

[socalhatch]

Well that did not seem to work. Went and plugged the ross tech in car seemed to misfire still with the evap pluged.

 

[Diggs24]

Let it sit overnight then pull the plugs and coils and see if there is fuel pooling into any of the cylinders. Also, log it with the IE cable while you start it to see what is happening.

 

[socalhatch]

i'll let it sit then check the plugs and coils. As far as the logging I sent IE a log of the car at idle on first start up and a 3rd gear pull as they recommended. They said everything looks good and no indications of a misfire. But i call b/s if i can get my car to misfire every time i plug it in. Went for a drive just a bit ago and got cylinder #4 to 100, cylinder #1 around 19 and the #2 and #3 around 11. Weird thing is after shutting the car off and re logging cylinder misfire seemed to switch to number 1 with the high count of 19 and #4 of 11.

 

[socalhatch]

have not had a chance to check the plugs and coils after sitting over night yet i will this weekend. How ever i switched tunes over to the burble tune on the 31st and the CEL did not pop up until tonight. heres the log attached to this post. Same b/s different file with same misfire cold start issues.

 

[mrobin44]

I came across this thread while googling for my issue which is similar. Did you ever figure out what was going on?

I have misfires only on cold start and they go away after 30 seconds or so when the idle drops down. The majority are on cylinder 4, but they all occasionally throw a few.
I just finished a carbon cleaning with no change. Swapped the coils around and took a look at the plugs. I guess injectors would be the next step?

 

[scrllock]

I came across this thread while googling for my issue which is similar. Did you ever figure out what was going on?

I have misfires only on cold start and they go away after 30 seconds or so when the idle drops down. The majority are on cylinder 4, but they all occasionally throw a few.
I just finished a carbon cleaning with no change. Swapped the coils around and took a look at the plugs. I guess injectors would be the next step?

how many? cold start misfires is very normal, doubtful you can eliminate them with new parts.

 

[socalhatch]

Honestly i dont know. I put EQT coil grounding kit on and either misfires stopped during that time or that fixed it but i doubt it. Maybe i had a bad batch of fuel? I run E85 about 98% of the time now and had a CEL pop up the other day for cylinder #2 misfire during start up. I noticed the car doesn't like to warm up at idle rpm so i just rev it to 1k during warm up.

 

[mrobin44]

how many? cold start misfires is very normal, doubtful you can eliminate them with new parts.

On cylinder 4 I usually log between 30-60 misfires before the idle drops. On cylinders 1-3 I see very few.. 0-5. I'll trigger a CEL every 3rd startup or so.

If they were evenly distributed, I would be less concerned. I'm wishing I had pulled the #4 injector when I had the intake manifold off.