idles...REALLY ROUGH after tranny pull

Well I just finished putting in a new flexplate on my 88. 4.0 I didn't pull the transmission, I just unplugged a few connectors and pulled it away from the block as far as I could. Now that it is all back together, as soon as I start it, it sounds like the motor is breaking apart. It will idle fine for about 1/12 a second, then man it really shakes. Is there something that I may have pulled tight that I am not seeing that oculd be causing this. I am totallly stumped.....

jephs422 said:

Well I just finished putting in a new flexplate on my 88. 4.0 I didn't pull the transmission, I just unplugged a few connectors and pulled it away from the block as far as I could. Now that it is all back together, as soon as I start it, it sounds like the motor is breaking apart. It will idle fine for about 1/12 a second, then man it really shakes. Is there something that I may have pulled tight that I am not seeing that oculd be causing this. I am totallly stumped.....

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did you put the 4 bolts back in the torque converter and torque em down?

yep, down to 40lbs. and the flexplate to crank bolts are torqued to 105 lbs

jephs422 said:

yep, down to 40lbs. and the flexplate to crank bolts are torqued to 105 lbs

Click to expand...

did you hook up the cps? and other conectors? also check the map sensor vac line

cps is hooked up, the Map sensor has vaccuum lines attached....but I may have goofed the cps sensor. I forgot to remove it when I pulled the trans, but I am assuming, that if I broke it, then the truck wouldn't run at all. I don't thin kit would cause a rough running symptom.

Okay, I've crawled underneath it and looked around a bit. Here's what I got so far.

1. Upon initial start it runs a little rough, but not too bad.

2. My Jeep has a tendency to idle at about 1500 for a few seconds. it does not vibrate too bad at this rpm.

3. At about 1000 rpm it is gawd afwful

4. at 700 rpm it fells the same as it does at 1500.

5. the vibration is not too bad at the oil pan. not too bad at the trans pan, but awful at the bellhousing.

is there more than one flexplate for my year Jeep? Maybe I got the wrong one? they looked identical in diamater and had the same balance holes.......

HELP!!!

I'm thinking that maybe the flexplate is offcenter.....but I don't know how.

nothin?......