Problems associated with broken flexplate
Just wanted to throw this out there for anyone who is banging their head against the side of their Jeep. I just spent four years and lots of time and money trying to figure out what the hell was wrong with the Jeep. Went to various threads and posts trying to get info and trouble shoot all the symptoms. Had it in two seperate shops and left cussing them cause they couldn't find the problem. So what was it you ask? Well, here goes.
Started out having a problem with power loss at higher speeds. Had a hard time holding on to 55mph. Anything above that was a pipe dream. At the slightest uphill grade had to down shift to pull the hill. (BTW she is an automatic)Well with all of the downshifting and high RPMs she was overheating.
Fuel milage was terrible. The best I could get was 12mpg.
And finally the exhaust. It finally let go at the colector and I had to replace the entire system. Exhaust manifold, Oxygen sensor, Cat, and Muffler. Once all of this was done the power loss was much worse. To say that it didn't have any power would be an understatement. Put it on the rack and the new exhaust was glowing.
Well after aproximately another 10hrs. of diagnosis we droped the tranny. Why cause we wanted to see the flex plate. Sure enough the flex plate was broke, Not cracked, BROKE. Center punched clean out. Had wedged itself so that it wasn't flopping around or making any noise. This caused the timing to be off and also affected the timing advancement when needed.
Replaced the flexplate and now have all the power I need. My fuel milage has increased to 16mpg. and I couldn't be happier.
So if you are experiencing loss of power, overheating, poor fuel milage, down shifting at the slightest uphill grade. Check your flexplate!