hesitation during acceleration and runs likes its missing

[Katzer]

Okay fellas...long story....

 

1989 2.5L 2wd. When I first got this beauty it had a hesitation/constant stutter with lack of power during acceleration.  It initially stumbles on start up but a short touch on the accelerator and it purrs like a kitten. On acceleration it runs like it is not getting enough fuel or too much.  The  jeep had sat for a while so I dropped the tank and cleaned it. While I was there I put a new fuel pump in it. I changed the fluids and put new plugs and wires in it.  The distributer looks brand new so I left it.  That didn't fix it.  So I refreshed all the grounds, shiny as a new penny. Didn't fix it.  I traced and fingered every vacuum line searching for holes like a 16 year old in a 2 dollar lady of the night house.  Found some leaks..Didn't fix it.  So I started testing sensors.  Everything tested fine except for my Manifold Air Intake Sensor.  It was way out of the spec that I found on here. I went to the parts store to find out they couldn't get it.  Researched online and yep..its not made anymore.  I cleaned the connection and tried to remove it... not gonna happen Cap'n!  Its gonna twist off and break.  I posted on here and was told to tighten my intake manifold bolts and clean/check connections again.  So I did and SURPRISE it was fixed!!!!! 

 

Fast forward 3 glorious weeks of smooth 2.5L Comanche drivin'.  Was driving home in the rain and the stutter returned.  I have rechecked the manifold bolts, the sensor connections, refingered vacuum lines, recleaned grounds, CPS looks clean, took off distributer(it looks new inside also) I have tried everything I can think of.

 

 

Please help.

 

 

[cruiser54]

Okay fellas...long story....

 

1989 2.5L 2wd. When I first got this beauty it had a hesitation/constant stutter with lack of power during acceleration.  It initially stumbles on start up but a short touch on the accelerator and it purrs like a kitten. On acceleration it runs like it is not getting enough fuel or too much.  The  jeep had sat for a while so I dropped the tank and cleaned it. While I was there I put a new fuel pump in it. I changed the fluids and put new plugs and wires in it.  The distributer looks brand new so I left it.  That didn't fix it.  So I refreshed all the grounds, shiny as a new penny. Didn't fix it.  I traced and fingered every vacuum line searching for holes like a 16 year old in a 2 dollar lady of the night house.  Found some leaks..Didn't fix it.  So I started testing sensors.  Everything tested fine except for my Manifold Air Intake Sensor.  It was way out of the spec that I found on here. I went to the parts store to find out they couldn't get it.  Researched online and yep..its not made anymore.  I cleaned the connection and tried to remove it... not gonna happen Cap'n!  Its gonna twist off and break.  I posted on here and was told to tighten my intake manifold bolts and clean/check connections again.  So I did and SURPRISE it was fixed!!!!! 

 

Fast forward 3 glorious weeks of smooth 2.5L Comanche drivin'.  Was driving home in the rain and the stutter returned.  I have rechecked the manifold bolts, the sensor connections, refingered vacuum lines, recleaned grounds, CPS looks clean, took off distributer(it looks new inside also) I have tried everything I can think of.

 

 

Please help.

Did you scrape the attaching point for the braided strap on the firewall to bare metal? 

[Katzer]

All my grounds are as shiny as i can make them. Cleaned elec connections yesterday and now it runs worse. I think i have a bad wire or connection somewhere. Gonna give it another try this coming week.