94 Jeep Wrangler

Tiny
SCOTTY000
  • MEMBER
  • 1994 JEEP WRANGLER
I recently bought this 94 wrangler it has an automatic trans. And I think a 2.4 ltr. 4 cyl. Eng. With over 100,000 mi. On second eng. Is what I was told, it runs great at an idle but when I get up around 40-50mph. It starts cutting out backfiring etc. I can shut it off and turn it back on and it quits for a little while but then does the same thing, it has good fuel press. I checked it, any ideas?
Wednesday, February 7th, 2007 AT 5:28 PM

8 Replies

Tiny
2CARPRO JACK
  • MECHANIC
  • 11,533 POSTS
Try an ignition coil
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Wednesday, February 7th, 2007 AT 7:00 PM
Tiny
SCOTTY000
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Thanks I will try that this weekend
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Thursday, February 8th, 2007 AT 6:38 AM
Tiny
SCOTTY000
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Tried a new coil this weekend, that didnt do the trick, put new plug wires on that seemed to take the backfire away, but now when I rev the motor up a little and hold it steady it surges up and down, could this be the fuel pressure regulator or maybe a vacuum leak? Help please. Thanks, scotty
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Monday, February 12th, 2007 AT 12:06 PM
Tiny
2CARPRO JACK
  • MECHANIC
  • 11,533 POSTS
Could be either one. Also test fuel pressure to be sure it is within spec
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Monday, February 12th, 2007 AT 4:10 PM
Tiny
SCOTTY000
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What should the fuel pressure be, pressure regulator seems to be working fine, but I still get an up and down surge while holding the throttle at steady speed?
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Thursday, February 22nd, 2007 AT 12:44 PM
Tiny
2CARPRO JACK
  • MECHANIC
  • 11,533 POSTS
I think your Jeep is gonna have to go on a scanner to watch the sensor outputs. What you are describing could be many different things
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Thursday, February 22nd, 2007 AT 1:52 PM
Tiny
SCOTTY000
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My fuel pressue is 24-25 psi book says its supposed to be 31, could the 6 psi difference make it act like this? I also did the test it called for in the manual and the pressure never changed. It does not surge up and down any more with steady pressure on the throttle, I dont know why it quit all I did was put a new exhaust system on. The engine idles great but when I get it on the road right before it shifts it stalls and backfires through the throttle body. Anymore suggestions before I put it on the computer?
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Wednesday, February 28th, 2007 AT 1:20 PM
Tiny
SCOTTY000
  • MEMBER
  • 10 POSTS
TURNS OUT IT WAS A WEAK FUEL PUMP CAUSING MY PROBLEM, SO I FIXED IT, DROVE IT TO GALVESTON AND IT WORKED FINE GOING BUT ON THE WAY BACK IT STARTED A NEW PROBLEM. IT WOULD DIE ON ME WHILE GOING DOWN THE ROAD, I COULD TURN IT OFF, CRANK IT UP AGAIN GO A FEW THOUSAND FEET AND IT WOULD DO IT AGAIN AS SOON AS I HIT THE GAS PEDAL, WHEN ITS COLD IT WILL CRANK UP AND RUN FINE UNTIL I HIT THE GAS PEDAL THEN IT DIES AGAIN. ANY SUGGESTIONS?
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Thursday, March 22nd, 2007 AT 11:40 AM

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