DWS964

I hooked up the Scantool to the "new" widebody last night to see what codes, etc. were present. I finally have put about 100 miles on the car (crappy weather and roads....), and it seems to run pretty good. One thing that I noticed was the absence of the sound of the resonance flap opening up at around 5000rpm, and thus why I wanted to check things with the Scantool. Under the Test Outputs, I was able to confirm that the resonance flap does operate properly. Two things that showed up:
- the WOT switch would not come ON when the go-pedal was floored. I lengthened the rod under the gas pedal, and now the WOT goes ON. The throttle was simply not fully opening. I expect to get at least 25 more HP out of this "modification". Need to let the weather clear up again, and test this out.
- the Motronic showed Code 41- Control Unit Faulty - I cleared the code and restarted the car and the code came back after the second restart. The oddity is that the car seems to run fine and all inputs and outputs seem to be performing "normal".

In the Search, I found a reference to Checksum that will throw the code. And another reference that suggested that an aftermarket chip may be present and cause this code.

Thoughts from anyone?
I know....If it ain't broke, don't fix it. But, I am an Engineer - everything needs fixed.

mojorizing

The bottom two numbers that the scantool reports should correlate to the checksum table you reference...

261200450 and 126735344 correlates, does yours?

mojorizing

I think you'll need to crack open the ECU a determine if you have a custom chip though, which I think you must have.

Nice widebody, too!

DWS964

Thanks for the info and suggestions. I will hook up the Scantool this weekend for a re-check.
Does anyone have a helpful procedure for opening up the ECU to view the chip?

I know..... if it ain't broke, don't fix it.

mojorizing

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