So my 98 xj dies at random. Driving for about 30 40 mins it while just die. No sputters chugging nothing. Then you let it sit for a half hour or so an it will start back up. Drove to safeway today, came back out an it won't start. Let it sit am then it starts.

No idea what's going on. Any ideas

 

Sounds like possible fuel pump. Check fuel pressure at rail

 

I get that it could be losing pressure but why would you have to wait to restart

 

Yours is distributor or coil packs?

 

Start it, wiggle the cps wires down by the trans where it connects, see if it dies. Probly a bad wire/connection. They like to melt in that area. btw its a 98, so dist.

 

Yeah either cps or the distributor. Not trying to thread jack at all but mine just started running rough and backfiring when its cold. Once warm runs normal. Any ideas anyone?

 

Fuel pump is a possiblity, but more then likely the CPS, TPS or IAC (replace CPS first, then TPS) and clean or replace the IAC.

Also of note, the distributor ignition pickup coil may be on it's last legs.

 

Upstream O2 sensor

 

I used to have the same problem for me the problem was a crank position sensor try that if you don't find the problem.

 

Mine did it, it was the coil.

 

I agree the cps... I noticed when I cleaned mine it worked for some time, but I ended up replacing it

 

I am dealing with this **** right now...

CPS: New
IAC: New
Ignition Coil: New
Ignition P/U (whatever the think under the cap is): New
Wires: New
Rotor: New
Wiring looks good
Fuel pressure off of the valve:
Idle: 50 psi
Accelerate: 42 psi
From what I have researched on another forum, that's fine.

Through this process...
Sometimes it starts....
Sometimes it doesn't....

After warrantying all of the spark parts, it won't even start.
Only code we have thrown through this process: P0505

Next???
PCM????

 

Sounds like Crank Position Sensor. My 98 would get hot sitting in traffic, die suddenly with no warning, and not start until it cooled off about 40 minutes... I replaced a lot of stuff but the CPS sensor finally fixed it.

I got the dealer item on this one because it's crucial to the engine running and supposedly has the correct magnet strength unlike many cheaper ones that are risky even when new. And it's not the easiest thing to reach so I only wanted to do it once. You can reach it with several ratchet extensions, about 3 feet long and a swivel at the socket.

I haven't had a problem with it now for about 6 months, it runs perfect and never dies.