Hi Brent,

We've never met before but I've been talking with Mike (Audi2ptzero) about a problem I'm having with my A4. It's a 2000 w/ K04, FMIC, and GIAC J31 software. Ever since I got the FMIC installed, the car is acting funny. I'll get one good run at WOT where the car works like it should, goes up to full boost (27-28psi for this chip), then drops into a sort of limp mode, except that if I continue to push it in this "limp mode", the boost starts to gradually go up from the original 7-8psi peak to anywhere from 16-20 or so. I've been trying to figure out the problem, and Mike was helping me see if it might be the MAF, although that's not looking like the case. I logged block 114, the N75 duty cycle, to see if that would have anything to do with it, but I realized I didn't know what right and wrong looked like. :)

The N75 was peaking around 55% or so, and I don't know if this is normal or not. Mike said to come to you as you have dealt with the N75 more, and I was wondering if you could let me know what normal readings should look like? I'm suspecting some sort of boost leak will eventually be the problem, although it is also curious the way the boost will run perfectly once, then go into limp mode. Makes me think the software is getting confused. Oh, and I get a consistent 17695 or whatever the code is, charge pressure control positive deviation. So if there's any advice or help you can give me, that'd be much appreciated.

Thanks a lot. Hope to hear from you soon.

-mikey

I'd try that. If they don't match, then I'd say it's an N75 valve problem.

If they match, which they probably will, then it's probably not the N75, since it just does what the ECU tells it to do.

Is the car running more, less, or same boost since the FMIC went in?

...a change of software accompanied the addition of the FMIC (from the GIAC v. K05 to v. J31)... So I don't know, everything being equal. I don't remember what it was like exactly before I moved up to J31. There were problems with K05, and I thought maybe I just needed to put in the FMIC software, so I did, but same problems.

The car is *supposed* to be running more boost, and in the first run after I start it up at WOT, it does. It peaks to around 27-28psi, like it is supposed to, and feels damn fast too, but then after that it appears to be in limp mode, although since the max boost steadily climbs after each WOT thereafter, it makes me think it's not *actually* limp mode.

Any thoughts? Thanks.

-mikey