My 2006 jeep wrangler rubicon has been idling rough and stalling while driving, especially when it shifts gears (its an automatic). The problem seemed to have started sometime after I had a K&N cold air system and new stereo installed. It was hardly noticeable, just had a slightly rough transition from 1st to 2nd gear. Then, while driving at about 60 mph on a road trip, my dog managed to get out of the little harness I keep her in for safety and she jumped up and hit the over drive button. I immediately pulled over and turned it off. No idea if that could have made any sort of a difference. Also, I had my jeep in 4WD at the beach earlier that day. (I didn't do any serious off roading, just used 4WD to get through some soft sand) By the time I was at a stop light in the next town, I noticed it sounded like it was idling high and rough. A few days later, the check engine light came on and the problem got much worse. Now my car idles rough 99% of the time. It will sometimes stall while sitting still in bother drive and park. It also stalls often while I am driving- Most frequently as it shifts into 3rd gear. My cruise control stopped working very shortly after the check engine light came on. It idles much more rough the lower my gas tank is. Could that be affecting it?when it stalls, it starts right back up. But only after I turn the car off, take the keys out of the ignition and then start it. My radio never loses power or turns off when it stalls. There doesn't seem to be a consistent pattern in which is stalls. But normally once it does it once, it will do it back to back about 4 -6 times and then not stall again for a while. It happens at all different speeds, sometimes while accelerating and sometimes while cruising.
It has gone into the shop 3 times and no one has been able to figure out the problem.
We have replaced so far:
map sensor (2 times)
spark plugs & coils
checked for any vacuum leaks
After they replaced the throttle body and TPS sensor, it ran really well for about 45 miles and then it went back to running rough... my mechanic is suggesting to send it to a jeep dealership to have the PCM replaced... I've been told that this is the last measure you should take when fixing a problem like this. What should I do? As a self sustaining college student, I am unfortunately not made of money.. I don't know if I can afford to troubleshoot my way down the long, long list of things what can cause a rough idle.
Any help or suggestions would be greatly appreciated.. PLEASE!
EDIT: Forgot to include this. But I have noticed that my dash lights will kind of dim and brighten with the rough idle. Not sure if that may be a hint at what it may be.