2000 TJ died and now it won't start

PJOJeep

2000 TJ Since New
Supporting Member
Joined
Jan 31, 2019
Messages
209
Location
Northern Illinois
Well, my always reliable TJ died while driving down the road today. I have a 4.0L, 5-speed and was driving down the road few minutes from home when the seems to momentarily die and the continue to run fine. It did it again and I noticed the gauges jumped up and down. I turned around to head home, it did it again and then stalled completely, would not restart...happened to have code reader in the Jeep, NO trouble codes showing.

So....working backwards on what I have done after I towed it home.

Fuel Pressure - turned on the key and verified there was fuel present at the fuel rail.

Recently I replaced the spark plugs with Champion Platinum plugs and a new Delphi coil rail. I removed the new coil rail and put the old one back on...still won’t fire.

Assuming fuel pressure is adequate, next I plan to crank it over, then pull coil rail and plugs to check if they are wet with fuel, injectors are original with 215,000 miles on them, just find it hard to believe all 6 plug up at same time.

Not sure how to check for spark with the coil rail. I don’t understand why no trouble codes, assuming it’s an electrical type problem!
 
My first step would be to spray starting fluid.

If it starts its something to do with fuel.

If it doesn't its spark.

This is also where I would start as well.

Also, check your fuel level!

My fuel level sending unit got stuck on the half way mark so I thought it had fuel. I kept starting it over-and-over and it would sputter and die. Well, I came to find out my fuel level was completely empty, but the gauge was stuck on half.

Just saying... rule out the simple stuff first!
 
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Have you looked at your main ground wire?
Especially because of the jumping gauges. Mine had a similar issue, ended up being a loose corroded ground.
 
Finally found time to look at it, starting fluid didn’t work. Grounds seem fine, engine cranks strong, just won‘t fire. NO codes being thrown. I took a chance and ordered a new Cam Shaft Position sensor, and Crank Shaft Sensor...will try replacing them one at a time. I hate chasing electrical gremlins!
 
Check your alternator. I had a similar situation while I was driving the engine lost power and struggled until I pulled off the road and all while the gauges were shooting around randomly. I turned the jeep off and couldn't get it started again and had it towed to the shop. My mechanic somehow got the engine going but noted the gauges is acting wildly and the voltage meter was low and believes the alternator was about to give out. A quick search on this site showed the gauges will behave weird if there isn't enough voltage and referenced an alternator issue. He installed the new alternator and it instantly fixed that problem.
 
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Verify that your ASD relay is activating, if it is that would indicate your crank and cam sensors are working.
Swapped it with the horn relay, horn still works...Jeep still cranks over fine but doesn’t start or fire at all.
 
Check your alternator. I had a similar situation while I was driving the engine lost power and struggled until I pulled off the road and all while the gauges were shooting around randomly. I turned the jeep off and couldn't get it started again and had it towed to the shop. My mechanic somehow got the engine going but noted the gauges is acting wildly and the voltage meter was low and believes the alternator was about to give out. A quick search on this site showed the gauges will behave weird if there isn't enough voltage and referenced an alternator issue. He installed the new alternator and it instantly fixed that problem.
Well, I replaced the alternator, checked the grounds, engine cranked over fine, voltage was a little low with ignition on so I put my charger/starter on it and voltage was over 12v...cranked strong, does not fire. I’m going after cam shaft sensor next, then maybe crankshaft sensor. Still no trouble codes come up. I did notice the Voltage dropped to almost 0 while cranking.
 
Swapped it with the horn relay, horn still works...Jeep still cranks over fine but doesn’t start or fire at all.

So the relay in the ASD location is activating while cranking the engine? The relay itself may be good, but without a valid cam & crank sensor signal the PCM will not activate the relay. If the relay is closing during start up you know your cam/crank sensors are good.
 
Well, weather finally improved enough to work on it in the driveway...and now have the correct MOPAR Crankshaft Position Sensor. I had ordered one from Amazon, ended up with the wrong one, so broke down and did the Mopar version. So, once it was installed, the Jeep actually fired and seem to run ok for a few minutes. When I tried to move it, it started missing and threw (3) codes: P0352 & P0353 (ignition coils) and a P1391 (Cam/Crank Sensor). Since replacing the camshaft position sensor didn’t fix the problem previously, I decided to put the original sensor back in. While I was at it, I replaced the coil rail with a new one I had. It started, ran very poor and same codes came back again.

I am going to try ordering a new Mopar camshaft position sensor next...just wo
 
Well, the Mopar Camshaft Position Sensor got installed, the trouble codes cleared and engine started and idled pretty good. Dumped in a bottle of HEET since it had been sitting since November, backed it and started to pull out of driveway for test drive...spitted and sputtered, CEL came on. This time only (2) codes, P1391 and P0352! I think I will try new plugs next...then not sure where to go.