Thread: Weird Drivability issues

Hello all, new to the form and have a weird issue going on with my wife's 04 GP. The car just hit 100,000 and I have completed a complete tune up. But it just started to do the following.
From 1700 -2000 rpms, the car cuts out sort of, the rpm gauge fluctuates back and forth bouncing and the car chugs, it does this when using the cruise, at speed with no cruise, also when sitting in the drive way in park. Another weird thing is, seems that it only does it on the highway when going down a grade, not while going flat or up hill. It has thrown no codes and has no issues other than that, runs great just like a striped, well you know the rest. I don't want to start throwing parts at it, looking for some suggestions and/or a way to test the "Accelerator Pedal Position Sensor" as I am thinking that it may be the culprit. Does any one have any ideas or maybe had the same exact issue and has fixed it ?

No Codes, that's what is weird. I did clean the throttle body, didn't help. Took of the accelerator pedal it looked good, hooked up an OHM meter and played with it through the motions, never did get a dead spot or anything, still not ruling this out, but don't look like it is it either. IDK I guess I will have to wait for a code, but I hope whatever it is , won't leave us stranded. One more thing that I did forget to mention, really don't see how this could have anything to do with it, but right before It started this, I had changed the Serpentine belt, PCV and Air filter.

Did you replace the o-rings on the PCV correctly? Might be just a huge vac. leak. Not sure on the 04's but I know prev. years had 2 orings and a spring in the PCV area. One on the PCV itself, then spring on top, then large oring in the UIM.

Originally Posted by FordMan77

Did you replace the o-rings on the PCV correctly? Might be just a huge vac. leak. Not sure on the 04's but I know prev. years had 2 orings and a spring in the PCV area. One on the PCV itself, then spring on top, then large oring in the UIM.

Interesting that you say that, I didn't change the o ring, because I forgot about it and it didn't come out when I pulled the old PCV. I will pull it again to make sure it didn't get crossup in there. Boy that would be a cheap fix, not to mention, DOH.

Originally Posted by NegativeOne13

Sounds like an issue I was having with my '05. I had pretty much the same symptoms and replaced the APPS hoping it wasn't the TCC. Ended up being the TCC and the tranny was replaced under warranty. The best thing to do is hook up a scan tool that shows real time data (i.e. Snap-On Solus), and take it for a drive. When the RPM fluctuates watch to see if the TCC is locking up or not. Also try enabling the lock up via scan tool to see if the fluctuation goes away. Not all tools will allow you to lock up, but hopefully you know a friend that has one that you can borrow.

I doubt that is the problem, but you never know, because it does it in park as well. It will do it when ever the car is not under load on declines, stand still, cruise or manual foot pressure. Above post might be on to something, because it all started right ater the belt, PCV and Air Filter change. Will be checking things out again. Love all the input, makes my brain work out of the box.

Well I'm not sure if it is fixed or not, but I think it may be. It turns out that there is a second o-ring on the PCV, pulled it last night and installed the second one. Tried to get the car to do it sitting in the garage and she ran like a champ. Will report back tonight to se if the .02 cent o-ring was the cause.

Awaiting report