Does a misfire permanently damage/alter a coilpack?

[n7plus1]

Diagnosticator, I would appreciate your input as I reference something you said a while back, IIRC.

I was chasing down a misfire and diagnosed my old ass 2.0T CP's as the issue after a few years of use (06H's).

Replaced with the "R8" coilpacks (newer red ones) and a fresh set of spark plugs, BKR7E-11's at the factory .044 gap.

They seemed to work great for a while but now I'm back to my random 3rd or 4th gear full throttle/boost misfire(s).

I'm thinking my issue lies in the coilpack harness itself now as all of the other possibilities have been rendered as good.

My question is since there is still a misfire randomly happening at full boost, is this affecting the coilpack(s) at all. I thought I remembered Diagnosticator saying that once something in this system shorts out (misfires), it permanently stays this way until its replaced? Maybe he meant when the issue is the CP itself...as in, the short is in the CP itself, it will always have an issue? I wasnt sure if the problem was in the harness, aka - a short in the harness BEFORE the CP's...would that be the same issue, or not affect the CP's at all?

[gregory.fazekas]

Your gap is WAY too large...I ran .28 on my b6 a4. Try gapping your plugs to what .32, what those plugs come with stock and that should help

[FromS60toB61.8t]

yea .44 is a bit much. I run between .28 - .32 as should any car with a turbo

[blownb6]

.28-.32 is what i would run with stock boost level on original coilpacks with r8 the fsi or tfsi i would be looking .40 on stock boost levels. with more pressure spark gets blown out so i would gap them down to .35 it will all be fine

[LINDW4LL]

+1 on gap being way too big. Try .032

[LINDW4LL]

.28-.32 is what i would run with stock boost level on original coilpacks with r8 the fsi or tfsi i would be looking .40 on stock boost levels. with more pressure spark gets blown out so i would gap them down to .35 it will all be fine

Not sure why people insist on running a large gap with FSI coils. Notice that the 2.0TFSI's gap is .032 as well with the updated coils.

[blownb6]

Not sure why people insist on running a large gap with FSI coils. Notice that the 2.0TFSI's gap is .032 as well with the updated coils.

small gap = weak spark, wide gap = blow out

and just to correct my self its .0-- not .--

[n7plus1]

Most of use who are running the 2.0T and up CP's are running that .044 plug gap...without issues. I never used to have issues when i first started running it about 3 years ago...the only thing thats aged since then is the CP harness.

[CyberPMG]

.028" - .032" is the recommended spark plug gap when running on the 1.8T coils.

.038" - .044" is the recommended spark plug gap when running on the FSI coils.

There's numerous threads on this. For most people running FSI coils the stock gap that comes from the BKR7E-11 and BKR7EIX-11 plugs.

As for damage to the ignition coil. lack of spark should not cause any damage that I'm aware of. Sometimes, the misfire could be the coil itself and not the plugs.

[n7plus1]

.028" - .032" is the recommended spark plug gap when running on the 1.8T coils.

.038" - .044" is the recommended spark plug gap when running on the FSI coils.

There's numerous threads on this. For most people running FSI coils the stock gap that comes from the BKR7E-11 and BKR7EIX-11 plugs.

As for damage to the ignition coil. lack of spark should not cause any damage that I'm aware of. Sometimes, the misfire could be the coil itself and not the plugs.

Plugs are new and coils are new..the only thing left is the coil harness.

[CyberPMG]

Plugs are new and coils are new..the only thing left is the coil harness.

As old as our cars are (9-12 years old), the engines have gone through a crapload of heat cycles that can make the ignition wire harness become exposed, brittle, and crack. Fortunately there are kits to replace the ignition harness either partially (around the engine block) or completely (coil to ECU).

I originally had the wire harness replacement kit from 034 which replaced the harness only from the coil to the back of the engine (where it gets the most heat). That was fine for a few years, but later found a crack in the remaining part, so I had the whole ignition wire harness portion replaced using a kit from USP Motorsports. Also purchased a 2.0T FSI ignition coil conduit normally found on the Mk 6/7 VW GTI. Adds protection and cleans up the appearance.

[blownb6]

Diagnosticator, I would appreciate your input as I reference something you said a while back, IIRC.

I was chasing down a misfire and diagnosed my old ass 2.0T CP's as the issue after a few years of use (06H's).

Replaced with the "R8" coilpacks (newer red ones) and a fresh set of spark plugs, BKR7E-11's at the factory .044 gap.

They seemed to work great for a while but now I'm back to my random 3rd or 4th gear full throttle/boost misfire(s).

I'm thinking my issue lies in the coilpack harness itself now as all of the other possibilities have been rendered as good.

My question is since there is still a misfire randomly happening at full boost, is this affecting the coilpack(s) at all. I thought I remembered Diagnosticator saying that once something in this system shorts out (misfires), it permanently stays this way until its replaced? Maybe he meant when the issue is the CP itself...as in, the short is in the CP itself, it will always have an issue? I wasnt sure if the problem was in the harness, aka - a short in the harness BEFORE the CP's...would that be the same issue, or not affect the CP's at all?

i say coilpack harness is not an issue here the highlighted points in RED is whats telling us that the gap is too LARGE gap them down and enjoy your car.

regardless of plugs being new, they still need to be gapped from .044 to .035 -.038 anywhere in that area

[n7plus1]

As old as our cars are (9-12 years old), the engines have gone through a crapload of heat cycles that can make the ignition wire harness become exposed, brittle, and crack. Fortunately there are kits to replace the ignition harness either partially (around the engine block) or completely (coil to ECU).

I originally had the wire harness replacement kit from 034 which replaced the harness only from the coil to the back of the engine (where it gets the most heat). That was fine for a few years, but later found a crack in the remaining part, so I had the whole ignition wire harness portion replaced using a kit from USP Motorsports. Also purchased a 2.0T FSI ignition coil conduit normally found on the Mk 6/7 VW GTI. Adds protection and cleans up the appearance.

Well, yeah, this is what i was trying to get at - I was going to start looking at replacing the CP wiring harness. Id go with the OEM replacement that ECS/USP/Europa sells.

i say coilpack harness is not an issue here the highlighted points in RED is whats telling us that the gap is too LARGE gap them down and enjoy your car.

regardless of plugs being new, they still need to be gapped from .044 to .035 -.038 anywhere in that area

Ok, ill gap them to .038 and go from there to test. It'll be a few weeks testing.

[FromS60toB61.8t]

Plugs are new and coils are new..the only thing left is the coil harness.

You're forgetting fuel can cause missfires as well. I had an old rotting Injector wire and was getting random missfires sometimes.

Worth a check, my 1st cyl injector wires were almost completely separated.

[redline380]

First off, FSI coils are fine at handling an .04 gap. I keep mine at around .038, but that's my preference. Not a single misfire to speak of due to coil/plug misfires. If OP is still on stock turbo, FSI coils can handle .044 no problem.

This might be a stretch, but when I was having issues kind of similar to yours, I too suspected coil packs, which is how I ended up with FSI coils in the first place. Turns out I had a blown turbo gasket which messed with my AFR's. Take a look at it. The turbo came loose and melted the gasket. Im not sure what your turbo setup is though.

Your harness could be brittle and have small cracks, but I'd suspect misses throughout the rev range. If it is only coming at full boost, you should be able to narrow it down from there

[Jermunji]

I keep mine .32 with the red toppers. They get hot but I figure with the boosted levels maximizing the spark strength was the best option. I originally gapped them to .44 as all everybody else typically does, but noticed some misfiring so started gradually finding the sweet spot which I felt to be between .32-.36. actually, on second thought I believe I did .34 to end at. Anyways keep trying different gap amounts to see what works best with your setup. every car is slightly different.

And maybe your dealing with a different demon altogether? Fuel pump or something random?

[Charles.waite]

I just want to chime in to debunk the misinformation regarding plug gap in here.

I've been running a .044" (1.1mm) gap on my 07K FSI coils for a bit over 2 years now with ZERO issues. No misfires, no issues starting. Nothing.

The FSI coils can easily handle that gap, flat out. That's a fact.

God I feel like I post this ad nauseum. People please research before you post garbage.

Now onto the OP's question. Honestly I would lean towards the wiring. Swap a coil pack and see if the misfire follows. If it doesn't, I think the wiring is the likeliest cause.

It's possible you have a cracked head I suppose but that seems to be much more rare than people make it out to be. Especially if you've never overheated your car.

Jermunji had another good point too. It could be a fuel pump or fuel pressure issue. How old is your Fuel Filter and is it OEM?

[blownb6]

I just want to chime in to debunk the misinformation regarding plug gap in here.

I've been running a .044" (1.1mm) gap on my 07K FSI coils for a bit over 2 years now with ZERO issues. No misfires, no issues starting. Nothing.

The FSI coils can easily handle that gap, flat out. That's a fact.

God I feel like I post this ad nauseum. People please research before you post garbage.

Now onto the OP's question. Honestly I would lean towards the wiring. Swap a coil pack and see if the misfire follows. If it doesn't, I think the wiring is the likeliest cause.

It's possible you have a cracked head I suppose but that seems to be much more rare than people make it out to be. Especially if you've never overheated your car.

Jermunji had another good point too. It could be a fuel pump or fuel pressure issue. How old is your Fuel Filter and is it OEM?

no offence charles since i joined this forum i see your posts all the time and 80% of the time you are just being a goof , different plugs dont work the same, if the harness was an issue he would be having missfires all the time not just under load ,

please educate your self on how forced induction works with ignition and timing(simple google search will explain , or grab a book and read it) before posting anything ,And who knows what kind of turbo setup the OP is running i am sure on a gt35 turbo you will not be able to run the same gap as on a k03

Its simple as more AIR BEING FORCED = PLUGs blowing out , henc high RPM/HighPressure missfire

I do agree with few people here about having a fuel issues. but i am sure it would throw some type of lean code.

And if people have posted here with experience on this subject why trash on other people?

[redline380]

no offence charles since i joined this forum i see your posts all the time and 80% of the time you are just being a goof , different plugs dont work the same, if the harness was an issue he would be having missfires all the time not just under load ,

please educate your self on how forced induction works with ignition and timing(simple google search will explain , or grab a book and read it) before posting anything ,And who knows what kind of turbo setup the OP is running i am sure on a gt35 turbo you will not be able to run the same gap as on a k03

Its simple as more AIR BEING FORCED = PLUGs blowing out , henc high RPM/HighPressure missfire

I do agree with few people here about having a fuel issues. but i am sure it would throw some type of lean code.

And if people have posted here with experience on this subject why trash on other people?

I think you need to be the educated one. As I stated before, I can gap my FSI coils to .04 or .044 if I want at 25 psi on a 2871r and have never had a misfire due to ignition issues. BKR7E's if it matters.

What experience do you have with FSI coils?

[evo_ski]

but i am sure it would throw some type of lean code.

Uhhhhh, I had a bad fuel filter (most likely the regulator inside it) that would cause a misfire under hard boost sitiations (above 10psi) and wouldn't show any issue under normal driving. It did not produce any kind of code when scanned with Vagcom. I changed the filter this weekend and have not been able to replicate the issue since.

And if people have posted here with experience on this subject why trash on other people?

Hypocrite much?

[LINDW4LL]

OP, this does not sound like a wiring harness issue. If it were a wiring issue, it would not only present itself under full throttle. You also said that when you previously replaced your coils, it ran fine for a while with no misfires. Again, if wiring were the issue you still would have had misfires after replacing the coils.

I just want to chime in to debunk the misinformation regarding plug gap in here.

I've been running a .044" (1.1mm) gap on my 07K FSI coils for a bit over 2 years now with ZERO issues. No misfires, no issues starting. Nothing.

The FSI coils can easily handle that gap, flat out. That's a fact.

No doubt, the FSI coils certainly can handle a larger gap. That said, .044 is at the upper limit, and it's possible that one coil is a bit weak for some reason. It doesn't hurt to go a little lower (I'd try .038") and see if his issue is resolved.

[Charles.waite]

no offence charles since i joined this forum i see your posts all the time and 80% of the time you are just being a goof , different plugs dont work the same, if the harness was an issue he would be having missfires all the time not just under load

Different plugs? We are running the exact same BKR7E-11 plugs. Well technically I'm running BKR7EIX-11 plugs, but I've run the copper versions before on my exact same setup and there is no difference. Your conclusion that a harness would cause constant misfires though isn't relaly accurate. Its never that simple. As the RPMs rise, the wires carry more current. more current means more heat, and more resistance. If the wires are compromised that heat could cause strange things to happen.

please educate your self on how forced induction works with ignition and timing(simple google search will explain , or grab a book and read it) before posting anything ,And who knows what kind of turbo setup the OP is running i am sure on a gt35 turbo you will not be able to run the same gap as on a k03

Yea okay man. I've been around for a while and I am somewhat familiar with n7plus1 and I'm pretty certain he's not running a crazy turbo setup. Also no shit a gt35 turbo has different requirements than a k03. It pushes about a million times more air. regardless howoever, the amount of air the turbo pushes is irrelevant. Its too high of a combustion chamber pressure that would cause a spark to not jump the gap ("blowout" isn't really an accurate term, the spark doesn't get blown out, it simply never occurs).

Its simple as more AIR BEING FORCED = PLUGs blowing out , henc high RPM/HighPressure missfire

Its not that simple.

Now after all this, keep in mind that turbo pressure on a stock turbo falls off drastically at higher RPMs. If it were spark plug/combustion pressure related, it would happen at peak boost wouldn't it?

Edit: And one more thing since it was mentioned, the FSI motors have a lower OEM gap because they have a higher compression ratio, it has nothing to do with the coil packs. Having said that I ran a .044" gap in both of my b7s in the past. I recently bought OEM Bosch plugs however since I'm selling, and noticed zero difference between them and the BKR7EIX-11s I ran previously. But my car was stock. Even with just a tune people often report the .044" gap results in misfires and many tuners suggest .032" or less.

[n7plus1]

Uhhhhh, I had a bad fuel filter (most likely the regulator inside it) that would cause a misfire under hard boost sitiations (above 10psi) and wouldn't show any issue under normal driving. It did not produce any kind of code when scanned with Vagcom. I changed the filter this weekend and have not been able to replicate the issue since.

i think i replaced it back in 2011...I usually sharpie the date on the filter body...

I only seem to get the misfire (which isnt every single time) at full boost for that specific gear. Still on a K03 too.

Id also like to add that the misfires arent being saved into memory (is that the right term?). If i run VCDS on it, nothing comes up. The CEL doesnt flash neither.

[evo_ski]

I replaced mine a year and a half or around 25k miles ago and it was already done for. Could still be a possibility. I had pretty much your exact symptoms.

[redline380]

i think i replaced it back in 2011...I usually sharpie the date on the filter body...

I only seem to get the misfire (which isnt every single time) at full boost for that specific gear. Still on a K03 too.

do you know which hole is misfiring? and how bad is it? like, car stalls bad or engine vibrates a little bad?

[n7plus1]

I replaced mine a year and a half or around 25k miles ago and it was already done for. Could still be a possibility.

ill check it out, pretty sure it was an OEM piece too.

do you know which hole is misfiring? and how bad is it? like, car stalls bad or engine vibrates a little bad?

no, sorry, my edit confirms i dont have any stored codes for it. The engine vibrates/stutters at full boost. The thing that gets me is that it doesnt do it every time.

[redline380]

no, sorry, my edit confirms i dont have any stored codes for it. The engine vibrates/stutters at full boost. The thing that gets me is that it doesnt do it every time.

hmmmm..... what kind of tune are you running and what kind of pressure?

[evo_ski]

Your newest edits sound even more like my issue. I had no stored codes or cel. I ordered the filter from europa on a gamble for $57. At least its not a terribly expensive part to gamble on.

[Furly]

.038 - .040 would be correct.
try to reduce the gap a little. i got some feeler gauges at autozone for cheep, measured them with a caliper to make sure they are correct and they are :)
i also run the R8 CP's

[imnuts]

Different plugs? We are running the exact same BKR7E-11 plugs. Well technically I'm running BKRyEIX-11 plugs, but I've run the copper versions before on my exact same setup and there is no difference. Your conclusion that a harness would cause constant misfires though isn't relaly accurate. Its never that simple. As the RPMs rise, the wires carry more current. more current means more heat, and more resistance. If the wires are compromised that heat could cause strange things to happen.

To add to this, the engine has different harmonics and vibrations at various engine loads and RPMs. Its possible that there is only a small crack in the insulation, and it can only get to a failure point to cause a misfire under certain conditions.

Sent from my Moto X

[FromS60toB61.8t]

If you have motoza run some logs and see what's happening.

It's sounds more to me that you're getting fuel cuts rather than missfires. When I got slight missfires it logged it into the system without a cel and just said random multiple missfires.

Run some logs, see what's going on with your ignition and get some maf reads. If no missfires get logged then I'd say check your fueling. Could even be a clogged injector.

I've gapped my plugs @ .032 always on any forced induction car I had with zero issues. Currently running 2.0 coils as well.

[n7plus1]

hmmmm..... what kind of tune are you running and what kind of pressure?

APR Stg 2+

Your newest edits sound even more like my issue. I had no stored codes or cel. I ordered the filter from europa on a gamble for $57. At least its not a terribly expensive part to gamble on.

Yeah, i may go ahead and replace that damn thing again.

.038 - .040 would be correct.
try to reduce the gap a little. i got some feeler gauges at autozone for cheep, measured them with a caliper to make sure they are correct and they are :)
i also run the R8 CP's

Last night i gapped them down to .038. Drove around for a few minutes, and drove it semi-hard this morning and got nothing so far.

It's sounds more to me that you're getting fuel cuts rather than missfires. When I got slight missfires it logged it into the system without a cel and just said random multiple missfires.

Run some logs, see what's going on with your ignition and get some maf reads. If no missfires get logged then I'd say check your fueling. Could even be a clogged injector.

I've gapped my plugs @ .032 always on any forced induction car I had with zero issues. Currently running 2.0 coils as well.

Im starting to lean this way too, especially with what evo_ski was saying. If this makes any sense: Usually when it happens, this is what it does - say im cruising around town in 4th gear, someone in front of me moves into the turning lane and i slow down slightly, I blip the throttle and downshift to 3rd, when I hit 3rd, ill go WOT, boost starts to get to peak and then it stutters/stumbles until i let off the gas.

[n7plus1]

UPDATE: still occurring with the lowered plug gap....

If it were my fuel filter, wouldn't my fuel pump be whining?

[evo_ski]

My fuel pump did not whine at all. I was getting a tapping noise at startup after the car sat for a long time, but otherwise everything sounded normal. The tapping noise has gone away after the new filter was installed.

[n7plus1]

I dont know of a tapping noise. Ill try to record the car from inside the cabin tomorrow morning so you all can hear the sound.

[evo_ski]

If you pull the rear bench seat bottom out it is easier to hear the fuel pump.

[LINDW4LL]

It could jndeed be the fuel filter or somethinf else fueling related. Woukd explain why you have no misfire codes.

[n7plus1]

I've heard the pump whine before , days later, Audi performed the recall on the car and replaced the pump and filter...that was back in 2008. I know I replaced in 2011 or the latest in 2012

[n7plus1]

I get my gas at my local SamsClub...I wonder if this is a problem or not? And very often run the tank down to nothing before putting more fuel in...

[LINDW4LL]

I get my gas at my local SamsClub...I wonder if this is a problem or not? And very often run the tank down to nothing before putting more fuel in...

Sams Club gas is likely not the problem. Running the tank down seems to be frowned upon by a lot of people, but unless you're basically running on fumes you won't be damaging the pump. I always run my tank down to near empty before filling up and have never had a fuel pump issue.