Got a bud whose car shudders on the 1-2 shift and throws the ABS Inop light. We've adjusted the shift points and used Datamaster to log the drive just to make sure that the car was shifting at the right point. It seems to be shifting when we've programmed it to and the tranny doesn't slip up to this point. Right at the shift theres a shudder from the rear of the car on the shift that is very noticeable and then the ABS Inop light pops on.


Thoughts??

 

May be the rearend , is it chirping good?
Deflection might simulate what the abs sensor thinks to be a slide etc.

 

The PCMForLess tune has the shift firmness included in the file but we got out of the throttle once the shudder started so i'm not sure how firm it would have shifted. 3.42's were just installed recently over the stock 2.73's.

His tach is currently not working and datamaster recorded seeing 5000 (give or take a hundred) on the log and the car shifted when it was programmed to (35mph) but the engine sounded like it was revved much higher. Question is, doesn't datamaster take the RPM straight from the PCM? So IF the car was actually revving higher than 5000rpm it would have logged it as such right? So, the log of 5000rpm that we have should be accurate straight fromt he PCM?