My friend just chipped his 1999 A4 1.8t and now when floored, it's jerky past about 3300 RPM. Replaced DV and it helped but the problem continues. He just bought it about a month ago and the previous owner had just replaced the turbo. Thinking it might be a mis-adjusted wastegate that worked at the stock half bar boost, but now opens too early and just flutters. Any thoughts or experience would be very helpful. Thanks.

 

could be a wastegate problem.. but it does take the chip a few weeks to fully adapt. If its still acting up after a few weeks then id have it looked at.

 

wait a couple weeks, than see whats up..

 

might be the N75 valve acting up that would cause inconsistant power

 

Check for codes, boost or vacuum leaks.

It should not take :"weeks" for the car to adjust.

Could also be failing coil packs.

If problem persists, take it back to your tuner to check it out.

 

2000 A4, 1.8TQ 110k

Thats funny to hear, I'm having that same problem. Chipped it and change DV, still jerky after 3000rpm. Vehicle still stock. Check it with Vag and no code however, when I gas it around 3500rpm, CEL starts to flash and then goes away. Check hoses for leak and all looks well. My next guess is the N75 solenoid valve is bad but no code to indicate that.

Playing with Vag-com now hoping to find something that looks out of the normal to indicate boost leak. Not sure what else to do. Let me know what your friend find out about his problem.

 

flashing cel is a misfire, it might not have missed enough to store a code, but it should have. Replace your plugs first if you have no fault codes to work with.

 

I don't think its the plug; had them replace at 90k with OEM plugs and they should still be fine since I'm at 110k. I'm idling fine and it drives normal under medium load but only when I try to give it full throttle or down shift at full throttle, jerks and act as if boost leak or serious misfiring. Thanks for the reply.

Thats why I was looking else where for the cause of the problem instead of ignition but I will consider that as an option if I'm all out of ideas.

 

My friend ran into the same problem with his VW GTI 1.8T with a APR chip and it turned out to be a coil pack. It was still replaced uder warrantee. Good Luck


Boost On
97 1.8TQ 5sp

 

Just to add to the flashing light. This means that there is a cat damaging situation. Most of the time caused by an extremely rich mix or a mis on the spark side