Been wrestling with a CEL as a result of following DTC:

16683 - Boost Pressure Regulation: Control Range Not Reached P0299 - 002 - Lower Limit Exceeded

for nearly four annoying months and was wonering if guys/gals can lend a helping hand.

My car is an 04' A4 1.8TQM with the following powerplant mods:

APR Stage II+ (subsituted the exhaust w/the Thermal R&D race) running on software v 2.0.

TT225 Injectors

Forge DVR w/Yellow Spring

NGK BKR7E's.

When the CEL first popped up back in May, I vagged the car and discovered that it was getting the "16683" code. I cleared the code and about a week later, the CEL popped up again.

Afterwards, the following steps were taken to diagnose the problem:

1. called APR: "It's an hardware problem..."

2. took it to the dealer to check for boost leaks and examine the DVR: none

3. took it to the dealer again for the smoke test: negative.

4. took it to the dealer yet again to get the boost actuator replaced.

By this time, I was seeing the "16683" regularly and clearing the code every week or so.

At the same time, I've contacted Andy @ Ross-Tech for suggestions and he furnished me with the usual battery of tests: 1. boost leak 2. dv 3. n75 4. software

Called APR again, "It's an hardware issue..."

Thinking that it might be the Forge DVR spring problem, I've switched the stock spring (green) to the next step up (yellow). This did not resolve the problem either.

So with the VAG, I measured and logged block 115:

<img src="http://www.ncaudi.org/gallery/albums/album258/Requested_vs_Actual_Boost.jpg">

As far as I can tell, the result seemed fine.

Has anyone else had this problem? If so what/how did you remedy it?

I am pretty much at the end of the rope and thinking whether I should get the car reflashed again or tinker with the n75 valve.

APR says their software is perfect, so what can I say?

Thanks in Advance <img src="http://www.audizine.com/forum/images/smilies/race.gif">
SP

 

There is no such thing as perfection, especially when it comes to APR and the B6. Again, you are one of many that are posting about problems with their software/bad service and customer support.

I met someone here with their Stage 3 and it as been nothing short of a nighmare for him so far.It as been months after months of wrestling with them to get parts and still the thing doesn't run right.

 

Yeah, that's what I said when I heard that... Jet, do you think all the options have been exhausted?

 

I also changed the boost sensor's,still the cel came back. My tech said it's the turbo and he was right so I changed the turbo and no more cel,my car is an 03 w/68,000 miles.

 

Which Turbo did you change it to?

 

Try swapping N75

 

which versions of N75? you reckon' reflashing the software alone won't remedy it?

 

You might also want to take logs on MAF and see whether MAF is dying or not.

 

for the MAF readings?

thanks,
SP

 

N75 takes at most 30-45mins on a cool engine bay..as for mesuring block for MAF is 2