why is the aeb a touchy bi@tch?

[mdfmk]

I have two issues that are annoying but knowing vag cars annoying will soon turn to catastrophic failure.

First issue is with the car dropping idle so low when i depress the clutch that it cuts out. this only has happened with the ac on so far. i just replaced the maf, coils and plugs (bkr7e .028 gaped) within the last 2 months.

Second issue is on a 3rd gear pull wot the car will randomly studder or misfire. this seems to only happen when the stars align right lol. If it happens it has happened while going up a incline (under a load) shifting from 2nd to 3rd and misfiring right away in 3rd. if i let off the gas for a second and re-apply the gas the misfire stops instantly.

little about the car, i recently put in an apr stg 1 91 oct ko3 chip w/ apr r1 dv, cone afe filter with new heat shield, and an oil catch can. other then that everything else is left stock. i have vag com logs on the maf and lambada if it helps. though from what i can gather my air/fuel looks ok.

[SlimChris76]

Whats your A/F at idle and under wot?

I run Denso IK20's in my AEB and I gap them alot closer (22)

[turboSlap]

I dint think its possible to get a correct a/f ratio on an AEB with VAGcom

[MetalMan1]

I dint think its possible to get a correct a/f ratio on an AEB with VAGcom

That's pretty much true. It will report lambda values that translate to about 14-15 AFR, but that's it.

Have you checked for vacuum/boost leaks? Any codes come up when these behaviors occur? Have you cleaned your MAF sensor?

[D3ZAudi]

It's the obsolete ignition. Doesn't allow a hot enough spark. Look into retrofitting the 2.0 coils which eliminates the icm.

[SlimChris76]

Sorry, I'm so used to having a wideband gauge. To troubleshoot, he could gap his current plugs closer and see if that resolves the issue. I'm on a big turbo and I still use the coils that came on the aeb from the factory and they work fine.

[mdfmk]

i have not done a leak test. its so random though. it will maybe happen once a day under hard driving conditions. if i granny it around then it runs flawless. i did run a n75j when i swapped over to the chipped ecu and when the 1st misfire first happened i went back to the "c" valve and it still happens. it never spiked over 16psi.
as for the maf its brand new, under 8k miles on it.
what gap would you guys recommend dropping the plugs too? i used to gap at .028 on my aww jetta w/ the same apr tune. but like stated before the ignition system is different on the aeb.

[SlimChris76]

I started with my AEB at .022, then worked my way up until it started to misfire, then backed it off a tad.

[Audiquattro337]

Is Mass air flow and lambda the only logs you can give us? If so post, along with any thing else you have. How about some freeze frame data for any codes you have, that would be incredibly helpful to diagnose intermittent issues similar to the one your having. gotta love OBD2<3

[ExtremeVR6]

There are two methods that are as close as you can get... Look up the Ross tech air fuel ratio calculation... You'll need blocks 4 and 31... Block 004 will allow you to calculate the air fuel ratio based on RPMs and the average injector on time...

While the AEB doesn't have a wideband
You can get a general sense of whether you're running rich or lean... The calculation isn't linear, but the scaling does provide generally trustworthy information when the voltage is between .8 and .9... Just multiply it by 14.7.

[ExtremeVR6]

Eh as close as you can get without installing a wideband

[Audiquattro337]

You can also look at LTFT/STFT, get a general idea if its running rich or lean, not exactly how rich or how lean though

[mdfmk]

How do I post the vag logs?

[mdfmk]

A little update... so I figured Id go with the aeb ignition weakness and gapped my plugs down to .024 and for the past couple days no misfires and my idle seems smoother. My next batch of plugs ill try .026 and see how she likes that. Thanks guys!

[MetalMan1]

If you wanted to dish out some extra $$$ (about $240) you could do a full-on ICM delete and 2.0T coilpack conversion (as suggested by D3ZAudi). I'm running a 0.040" gap on BKR7E plugs with 2.0T TSI coilpacks and it's silky smooth, with no misfires at WOT! (22psi)

[mdfmk]

I read a diy on converting to awm coils. The 2.0 coils better? I was planning on waiting till the icm died before I did the swap.

[SlimChris76]

Glad I could help you fix your problem without costing you any $

[MetalMan1]

If you run AWM coils you might be able to gap up to 0.032", but the 2.0T coils and a lot better than AWM coils even.

I didn't feel like waiting until one of my AEB coilpacks or ICM died, so I considered the ICM delete "preventative maintenance". IMO it's better to get rid of it before it starts giving you problems.

[mdfmk]

If you run AWM coils you might be able to gap up to 0.032", but the 2.0T coils and a lot better than AWM coils even.

I didn't feel like waiting until one of my AEB coilpacks or ICM died, so I considered the ICM delete "preventative maintenance". IMO it's better to get rid of it before it starts giving you problems.

Food for thought, thanks!

And thanks slimchris76 for the tip . I had a feeling it could have been that but didn't think the aeb ignition was that weak.

[SlimChris76]

Now the aeb coils don't send a strong spark, but they wont go out easy, They are reliable. The ICM is not reliable though. I keep an extra ICM in the trunk just in case. The ICM's on the newer models go out though... its just that on newer models each coilpack has its own icm built into it.

[mdfmk]

Now the aeb coils don't send a strong spark, but they wont go out easy, They are reliable. The ICM is not reliable though. I keep an extra ICM in the trunk just in case. The ICM's on the newer models go out though... its just that on newer models each coilpack has its own icm built into it.

yea I know I have a lot of experience with vw coils going out on my mk4 jetta. Thanks again

[SlimChris76]

No problem man, just helping out where I can