New Caprice - Discussion forums

RPM fluctuating from 400 to 600 lights are dimming and brightening while in park. I have replaced throttle body I was wondering if you guys could help me identify the idle air control sensor mass airflow sensor is good. Thanks

Lights dimming and fluctuating in park?

I would definitely load test/check your battery and alternator first.

It shouldn't be hunting like that, and yeah, what fudgehog says, check the alternator output and load test the driver's side battery. How many miles on it? I'd get a good data logger on it to see what your inputs are, and see if there are any codes set, and work from there.

Pending that, I'd run your hands around all of the vacuum hoses and make sure nothing is cracked or loose. I'm not terribly familiar with the V6, so I'd say to also check the PCV system. If it's got some miles on it, you may want to check/change the PCV valve and hoses.

Thank guys the throttle body just needed to be relearn

Good to know. Yeah, these cars are really sensitive to new stuff being put on them.

So what's the process for relearning the throttle body?

Thanks!

Use a tech2 scan tool or GDS2.

Either dealer performed, someone local and competent, or buy the VXdiag off Amazon and learn how to do it individually.