While driving today, my 08 Pacifica Touring AWD with 180K miles lit up its traction control/stability control light (car with squiggly lines behind it). I don't feel anything wrong, but when I let of the gas at highway speeds, sometimes it felt like it was "chugging" a little bit. I don't remember it doing this previously - its almost like the transmission wants to downshift from sixth gear when I would rather it coast since I let off the gas.

Any thoughts if its a sensor worth changing (like a wheel speed sensor)? How do I find out if one of the wheelspeed sensors is bad (preferably without going to a Chrysler dealer, but if I must, I must). Any other things worth checking?

Thanks for any suggestions.

Dave

 

I have also noticed that the vehicle is reluctant to downshift. When going froma downhill to an uphill travelling at 50mpg, it didn't want to downshift, so I switched to Autostick and downshifted from 5 to 4. I noticed after that a bunch of times where pressing down further on gas pedal would have typically led to a downshift that nothing happened. It manually downshifts and upshifts fine in Autostick.

Dave

 

It's pointless to guess at the possible problems. When the light comes on. it's because the computer has turned it on. The computer turned it on because of some detected fault. That fault will be stored in the computer. Get the car to someplace with a sophisticated code reader to download the fault code from the computer. A low level code reader may not be able to dig down deep enough to find the code in your computer. You may have to get the code read by a dealer or at least by a reputable shop with a dealer-quality code reader.

 

Agree w/ dcotter. Lots of computer module stuff going on in the background. The Codes are listed in the manual.

 

As a followup for anyone who comes for searching on this thread, the shutoff of traction control appears to be related to the computer putting the vehicle into a semi-limp mode. - this version of semi-limp looks like it tries to limit the engine rpm, and prevent going automatically into gear 6 or downshifting on hills. The problem was the cam and crankshaft position sensors didn't agree, which could have meant a sensor went bad, or it was real. I changed both sensors, and the problem remained. My mechanic said he thought saw some crusty debris from leaky antifreeze around the timing belt cover, and thought maybe a leaky water pump could have degraded the timing belt (about 30K miles on it) and made it jump some teeth. Between that repair, and most of the exhaust rotted out, he suggested scrapping the car at 180K miles. I ordered a water-pump/timing-belt kit, and planned on changing them out this past Saturday morning. The vehicle stalled out 9 miles from home on Friday night and would not restart. I had it towed to home since I already had the pump/timing-belt kit. When I got down to the timing belt, I found both camshafts about 4 teeth advanced ahead of the crankshaft. The existing timing belt had lost about half-its width in some sections, and there was a good bit of timing belt dust and small chunks of belt laying down near the crankshaft gear. I don't know what was causing the timing belt to loose chunks across its width.

After changing the water pump, the idler pulley, belt, and the hydraulic tensioner, the vehicles runs fine, traction control works, transmission shifts normally, and no "check engine" light. If the engine starts shredding the new timing belt, I'll fear something worse is happening.

Thanks,


Dave