RayBaer

So I have a 2001.5 S4, GIAC Chip and EVO Diverter Valves. That's it, car's a month and a half old for me and I've only just begun.

Now, Since I chipped the car, I immediately had driveability issues. The car would jerk and lurch at different parts of the RPM range while under 1/4 throttle. I brought the car in to Audi and they replaced a torn TBB. They also said my passenger side turbo was too loud and they ended up replacing both under warranty (HELL YEAH!). So anyhow, the lurching stopped, however I noticed that under light throttle it would still jerk a little bit. I guessed I might have been losing some boost still, so I went and installed the new diverter valves as well as installed a boost guage. The valves didn't really help much, but the guage has given me a good visual as to what's going on.

I've more or less pin-pointed it down to this: Under 1/4 throttle, accelerating from 3,000 to 4,000 RPM and boost between 0 and 5 psi, I can physically see the needle on the boost guage bounce back and forth between about 2 and 5 PSI. I can also feel this in the car, this is the "jerkiness" that I've been talking about. The interesting thing is, If I put the throttle down a bit more, the boost will jump to 10 PSI and hold solid. I also see a max of 16 PSI if I'm at full throttle. Is this stuf normal of a chipped S4? Or is there something seriously wrong with the programming.

Pat

There are certainly many other possibilities. I'm guessing someone more knowledgable that I here will chime in soon. Also, you may want to explain the situation to you chip vendor. I'm not sure how much they'd be willing to/could help, but it's worth a phone call.

RayBaer

Yeah, I talked to the shop that installed it, and they basically said that that's the chip out of the box, every car is different, and that has a generic programming. If I want to, I can contact Garret directly and see about custom programming, but I think that can get pricey, as well as I'm sure they are backed up indeffinately. My next step though I think will be an e-mail to them/him.

RayBaer

Anybody else going to take a crack at this?

S4Lee

Make sure you're running the latest chip software.