I think I am getting some Misfires? - Need help

[Dredknut]

I recently had the recall done for my coilpacks, all 4 were replaced under warranty.

Since then I have been experiencing what I think are misfires under certain conditions... Basically, when I am WOT in 4th gear or higher, 4k+ RPM I get hesitation from the engine and a blinking check engine light. When I let off the gas or just give it partial cruising throttle, the misfires stop and the check engine light disappears. This has happened on 2 occasions, and then finally today I have a solid check engine light.

Power delivery is normal in the lower gears at high rpm, the car still pulls well. I have no cold start issues, and I have replaced my cam follower within the last 15k kms with 2 oil changes since then and regular top ups. I don't have access to a vagcom, so I can't confirm the hesitation I am experiencing is infact misfires and not fuel cuts, etc.

I am convinced its faulty coilpack(s) that were installed, but I am also skeptical that it could be my plugs as well. I have an apt with the dealer next week, but I am curious if there are any other possibilities I should be considering? Am I on the right track?

Mods are as follows:
- APR Stage 1
- P-Flo with dryflo
- BSH DV
- BSH Stg 1 PCV
- NGK BKR6E plugs

 

[silversleeper]

check these:

-the coilpack harness(broken/loose clips)

-pull the coils and check for moisture/drity

-change back to stock plugs(see if that helps)

 

[silversleeper]

what type of gas?

any carbon build up?

 

[Dredknut]

I am APR 93, usually I fill up with Sunoco Ultra 94.

I ahve 96000km on my GTI, so I would imagine I do have some carbon buildup on my valves as I don't run a catch can.

I am thinking its either one of my coilpacks, my plugs, or my MAF sensor needs to be blown out.

 

[sd-mod]

bump for solution?? Did you figure out if it was the coilpacks or something else?

I am having the same issue and also on the new coilpacks as well... It is only happening in higher RPMs(4500 - 5000 range) at WOT usually not until 4th gear. I flashed stage 2 a few weeks after new coilpacks were put in though so I can't be sure if this is just fuel cut or misfires. No CEL has been thrown yet though. Haven't been able to vag the car yet.

 

[Dredknut]

I replaced my plugs the other day, solved my issues. The old plugs I pulled out (approximately 8000km on them, wtf), had opened waaaaay up so the gap was just too wide to get a proper spark under wot conditions.

I replaced them with new, properly gapped plugs, fixed my problem.

 

[VtecVick]

bump for solution?? Did you figure out if it was the coilpacks or something else?

I am having the same issue and also on the new coilpacks as well... It is only happening in higher RPMs(4500 - 5000 range) at WOT usually not until 4th gear. I flashed stage 2 a few weeks after new coilpacks were put in though so I can't be sure if this is just fuel cut or misfires. No CEL has been thrown yet though. Haven't been able to vag the car yet.

I have the same exact problem. WOT at 4500-5000 rpms misfires like crazy

 

[Dredknut]

^ If your getting misfires at WOT in higher gears its your plugs, they either need to be replaced or aren't gapped properly. Faulty coils tend to show other symptoms such as cold start issues, rough idles, etc. and cause these issues under pretty much all conditions, not just wot in high gears. Thats what I've read anyways.

BTW, I just had my CEL cleared and the code was p0304 misfire cylinder 4.

I've had some questions as to what plugs I was running. Ever since I replaced the OEM Bosch plugs I've always ran NGK BKR6E copper plugs. The only reason I had problems with the last set I installed is because I adjusted the gap slightly when installing them. The plug I put in cylinder 4 got bumped around in shipping and the gap was realllllly tight so I opened it back up to what I thought was 0.030". Apparently I just opened it up too much which caused issues for me down the road once the plugs had a little wear on them.

 

[VtecVick]

^ If your getting misfires at WOT in higher gears its your plugs, they either need to be replaced or aren't gapped properly. Faulty coils tend to show other symptoms such as cold start issues, rough idles, etc. and cause these issues under pretty much all conditions, not just wot in high gears. Thats what I've read anyways.

BTW, I just had my CEL cleared and the code was p0304 misfire cylinder 4.

I've had some questions as to what plugs I was running. Ever since I replaced the OEM Bosch plugs I've always ran NGK BKR6E copper plugs. The only reason I had problems with the last set I installed is because I adjusted the gap slightly when installing them. The plug I put in cylinder 4 got bumped around in shipping and the gap was realllllly tight so I opened it back up to what I thought was 0.030". Apparently I just opened it up too much which caused issues for me down the road once the plugs had a little wear on them.

So If I were to get some NGK's is the gapping on them need to be adjusted or there ready to go and be installed

 

[Dredknut]

They come pre-gapped at 0.030", and have protective sleeves over the "business end" of the plug to prevent the gap being altered prior to installation. In my case the box/sleeve was crushed during shipping so the gap was altered and when I attempted to gap them myself apparently I opened them up a lil too much.