99 Grandprix - Car jurks Trac light goes off and tach quits working

[twi119]

I have a 99 Gradprix GT. Every once in a while the car will jerk and
the tach will quit working and the trac off light will come on. Sometimes the car might even die. If you turn the ignition on and off the problem
will go away. Anyone have any thoughts on this?

[regalfriend]

i have a 1997 Regal GS,and have similar problem...while driving the trac off...anti-lock/trac light and brake light come on..When i let off the accelerator the car seems to stop itself because the brakes are being applied through the traction control device. When i turn the car off and restart it goes away.Some cars have trac-control through the use of the brakes, and some use a fuel system reducer, and ive heard some use both. Once the other AF Members view this im sure we'll get a pretty good answer...

[BNaylor]

The GTP and Regal GS (SC only) have the full range traction control system meaning it applies the brakes when a low trac situation develops.

The standard traction control system limits wheelspin by reducing power and upshifting the tranny via the PCM.

Most ABS and traction DTC error codes cannot be read by a basic odb-ii scanner but shops with higher level systems including the dealer with the Tech II machine can read ABS/TRAC codes which are in the CHASSIS code family and manufacturer specific. Higher up scanners like the Actron CP9145, etc. and up will read these codes. ABS codes will tell you which specific wheel sensor is bad, wiring or ABS modules, etc.

I found 99% of ABS/TRAC problems are the wheel sensor in the hub/bearing assembly and/or the wiring leading up to the wheel sensor connector which is routed on the lower control arm.

BTW - The problem sounds like a crankshaft position sensor (CKPS) going bad.





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