Problems associated with broken flexplate
#1
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Year: 1991
Model: Cherokee
Engine: 4.0 HO
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!
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!
#2
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Year: 1989
Model: Wagoneer
Engine: 4.0L I6
good info to know, have all those issues aside from the over heating, anyway im just starting the tear down to do a 5spd conversion and pulled the inspection cover to unbolt the torque convertor and go figure i see at least 3 breaks in the flex plate, should be interesting to see how bad it really is once its all off.
#3
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Year: Several
Model: Cherokee
Engine: 4.0
Wow - Interesting! Who'd a thought!
It obviously was still letting the CPS get a signal, but just at the wrong time.
I wonder if broken flex plates are common on these?
It obviously was still letting the CPS get a signal, but just at the wrong time.
I wonder if broken flex plates are common on these?
#6
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Year: 88
Model: Cherokee
Engine: 4.0
mine had broken as well as if the center had been punched out and replaced it but didnt gain anything by this and i still get 11 mpg the only thing i havnt changed is the o2 sensor thats next while i do the exhaust manifold as well but im waiting for that to arrive hopefully that helps im tired of driving that bad of a gas hog
#7
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Year: 1989
Model: Wagoneer
Engine: 4.0L I6
my brother works in a transmission shop and he says that cracked/broken flexplates are quite common on chrysler products.....good thing im going to the 5spd ive had enough of the issues when it comes to automatics
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