stalling/not running

2003 JEEP WRANGLER TJ
148,000 MILES • 4.0L • 6 CYL • 4WD • MANUAL
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LBECHIEF
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My Wrangler started "bucking" on the way to work, half way home quit completely. Fuel pump was my thought. Towed it to my shop, replaced the fuel pump and cleaned the tank. ran for a day then same problem. this time I noticed that when the "episodes" occurred the tachometer was diving to zero (ignition).

I will save you the story and just tell you what I have replaced so far. Battery and cleaned all terminals and connections, throttle position sensor, cam position sensor, crank position sensor, power distribution center (fuse box) apart and cleaned/checked all connections. disconnected cleaned all of the plugs and reconnected, same with the grounds through the firewall.spark plugs and coil.

started and ran fine until you move it. it stalls.
Nov 8, 2016 at 9:26 AM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.
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HMAC300
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check to see if harness is cut/worn through by rear stud on head, these engines do that. then scan for codes and check fuel pressure with a gauge. see link auto parts rent it.
https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator
Nov 8, 2016 at 1:31 PM
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LBECHIEF
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OK Off for Veterans day, Good fuel pressure, the harness on this one has a protective box around the back of the head, checked inside and saw no obvious breaks. also moved all of the harnesses while the jeep was running. Not a-lot of area here to describe, but it will run fine, no light no stored or pending codes. will take full throttle if you move the jeep 3 inches it shuts off and will not restart until you move it from that position. you can do this as many times as you want. at the suggestion of friend replaced the ASD relay, how is it activated? Thanks in advance, Greg
Nov 11, 2016 at 9:07 AM
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HMAC300
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if you replaced asd relay and it fixe dit then it was probably a bad relay. I forgot about that see pic for operation of asd relay the pcm controls that.
Image (Click to enlarge)
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Nov 11, 2016 at 9:29 AM
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LBECHIEF
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Thank You, I have already read that passage from the manual. I did replace the relay, then did the old disconnect and reconnect the battery, started, let it run until she was up to temperature, put my shoulder against the door frame rolled it about an inch and it shuts off just like turning the key off. I,m gonna put it up and pull all of the wheels, look for gremlins attached to the axles. I know on some other vehicles the "hit from the rear" sensor, anything like that to look for?
Nov 11, 2016 at 10:08 AM
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HMAC300
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no sensor s in the rear before you go into all that stuff try resetting security system on it that may be the problem. see link
https://www.2carpros.com/articles/how-to-reset-a-security-system
Nov 11, 2016 at 1:09 PM
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LBECHIEF
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another day in the garage, I watched the security thread, I don't believe there is any-sort of security on this wrangler. I also took the steering column covers off, I had turn signal troubles before, and there does not appear to be any sort of security on or around the key. I cleaned all of the connections there and tried again. The heep is up on stands, started let fully warm up, while it was idling I "shook" all of the wiring harnesses an connectors and she just purred along. rolled under, turned the driveshaft 1/4 turn and she shuts off. the only thing rotational I see is the speedometer transmitter.Help Or maybe the ECU.
Thanks in advance, Greg
Nov 14, 2016 at 12:02 PM
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HMAC300
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all cars have had a security feature in them since at least 1996 you won't see it , it can be a transponder in key and the module is out of site so if you still haven't done it do so. also check the battery as weak batteries cause all kinds of problem as well as the silly devices progressive insurance gives you to plug into the car. any type of stuff like that interferes with the computer.if you cannot pic up anything on a scanner have a mechanic hook up his he can test stuff that auto parts computers cannot this one sounds like an odd type of problem.
Nov 14, 2016 at 1:13 PM