2008 Grand Prix V6 CPS Problems

Posted by: gp2008

2008 Grand Prix V6 CPS Problems - 07/10/12 01:00 PM

I have a 2008 Grand Prix base model with a 3800-V6. For the past month it has been intermittently stalling. Over time it has been becoming more frequent. When it stalls the engine stops dead with no RPM fluctuation or sputtering. All electronics stay on. I have put a new AGM battery in per the advice of O'Reillys. It tested 320 CCA but was a 680 CCA battery. Afterwards the car continued stalling. I purchased a CPS from O'Reilleys and replaced it (BWD Brand). After replacing the CPS it stalls more frequently than before. I am wondering if I got a bad CPS from them. Any thoughts?

Since first posting I replaced the new CPS with the old one and I am back to the way it was before. I have noticed that the car has to turn over a few times for it to start now and it idles rougher than it did before.
Posted by: GP SE

Re: 2008 Grand Prix V6 CPS Problems - 07/11/12 06:38 PM

Sounds like the fuel oxygen senser.
Posted by: FordMan77

Re: 2008 Grand Prix V6 CPS Problems - 07/31/12 11:03 PM

A bad O2 sensor would throw a CEL.

OP- Is your CEL on? If not, then possibly try changing the fuel filter. Can you give us a better decription of when it stalls? Are you just drving along and it cuts out, coming to a stop, idling at a light?