Another CEL thread

[bensnorton]

01 1.8t. The car runs fine until it should start to boost, like 2500-3000 rpms. Once i get into boost it starts to skip and stammer continuously and the CEL flashes. If a let off the gas and go a little easier it stops skipping. I guess this is a misfire? I'll have to cel scanned tomorrow but does this sound like something relating to the turbo like a boost leak or something having to do with the coil packs or spark plugs?

[djwimbo]

sounds to me like you have a secondary ignition issue.

Check you plugs and make sure they're gapped correctly. Facelift cars are push down coils as well, pretty common to see the #3 and #2 coil take a dump.

the reason is misfires under boost is typically due to the added a/f mixture. The higher the VE the harder it is for the coil to produce enough power to jump the spark plug's gap

[bensnorton]

Ok, i'll check the gaps today. Is there anyway to test the coil packs or what?

[djwimbo]

without a scan tool or something to check codes with you're out of luck. Bench-testing the coils hasn't ever proven anything from what I've seen.

If you had VAG-com I'd say swap coils, like put them in "backwards". Change #1 to #4, #2 to #3, .... etc. and see if the cylinder that's misfiring moves with the coilpack.