Jeep Stalled and Died

Daniel.Lee

Member
Joined
Dec 3, 2018
Messages
62
Location
Cupertino, CA
Hello all,

I've got a 1998 Wrangler 4.0L with 128,000 miles and on my way to dinner last night the Jeep stalled and I couldn't get it to turn back on. I pushed her off into a parking lot and waited for a tow.
The tow truck driver tried putting fuel in as well as jumping it — of course, this didn't do anything. I don't suspect it's the battery, however, after a bit of research I'm beginning to think it is a bad fuel pump or maybe bad CPS/CKP.

A few weeks ago I did the Rubicon Trail and noticed that when I stalled on a steep incline, it was difficult to turn the engine back on. It would take a couple attempts of turning the key for 3-4 seconds before the engine turned over. However, on flat ground the engine turned over after half a second of turning the key.... I'm not sure if this was an early sign of the fuel pump failing?

Anyway, I would love your guys' input before ordering a $200 fuel pump and spending the time and effort in dropping the tank.

Thanks,

Daniel
 
What does "turn back on" even mean?

What does "It would take a couple attempts of turning the key for 3-4 seconds before the engine turned over" mean?

Are you saying that the starter doesn't even spin the engine for the first 3-4 seconds?

Correct terms to use:

Engine cranks (spins) but does not start

Engine doesn't crank (does not spin)
 
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What does "turn back on" even mean?

What does "It would take a couple attempts of turning the key for 3-4 seconds before the engine turned over" mean?

Are you saying that the starter doesn't even spin the engine for the first 3-4 seconds?

Correct terms it use:

Engine cranks (spins) but does not start

Engine doesn't crank (does not spin)


Yes, it cranks but doesn't start.
 
Remove the intake tube and spray starter fluid into the throttle body. If it starts and runs for a few seconds, it is a fuel delivery issue. If it doesn’t, check for ignition issues.
 
If it’s angle dependent it sounds like a pump / tank issue to me. Try driving up one a steep incline and shutting off / starting to see what happens. Have you ever had issues starting before?
 
Remove the intake tube and spray starter fluid into the throttle body. If it starts and runs for a few seconds, it is a fuel delivery issue. If it doesn’t, check for ignition issues.

I did this and it did not want to start. I checked the fuel pressure at the fuel rail and it was hitting 42psi while cranking the engine.

I tried to get a spark out of the ignition coil by putting an old spark plug in the ignition coil cable but saw nothing.
I also checked the ASD relay and it's working just fine. Also tried to jump the ASD relay and fuel pump relay but the Jeep still wouldn't start.

Is there any way to rule out the CPS and CKS? I am getting a pulsing signal out of one wire that goes to the ignition coil. The other I'm having a hard time measuring anything at all.

What could it be? The PCM seems fine .... my gauges work and my OBDII scanner is able to connect to it.
 
I am getting a pulsing signal out of one wire that goes to the ignition coil. The other I'm having a hard time measuring anything at all.
If you have a signal going to the coil and no spark then maybe the problem is the coil ground or what you are having a difficult time measuring. Did the coil ground or wires get damaged on the trail? Seems like signal in and no spark out means the problem is there.
 
If you have a signal going to the coil and no spark then maybe the problem is the coil ground or what you are having a difficult time measuring. Did the coil ground or wires get damaged on the trail? Seems like signal in and no spark out means the problem is there.


Hrmm, doesn't the coil ground itself through the two bolts that fasten it to the bracket? I don't think the coil/wires were damaged on the trail. It's in a pretty safe place and I didn't cross any rivers.
 
Hrmm, doesn't the coil ground itself through the two bolts that fasten it to the bracket? I don't think the coil/wires were damaged on the trail. It's in a pretty safe place and I didn't cross any rivers.
Is it possible that the new coil is bad, I mean signal in and no spark means bad right?

Just trying to focus on things you know are wrong.
 
Is it possible that the new coil is bad, I mean signal in and no spark means bad right?

Just trying to focus on things you know are wrong.

Yeah, but it's a brand new MOPAR coil so I'm less inclined to blame the non-existent spark on this component. Is there a test I can do on the ignition coil to ensure that it's functioning as it should?
 
Might be a bad rotor or cap also. Try hooking up one plug wire to the coil and check for spark.

I replaced the rotor and cap less than 5k miles ago with a new MOPAR cap and rotor. Also, I'm getting no spark out of the coil — I attached a spark plug to it and got nothing.
 
Yeah, but it's a brand new MOPAR coil so I'm less inclined to blame the non-existent spark on this component. Is there a test I can do on the ignition coil to ensure that it's functioning as it should?
Ya, hook ground up to the coil, put the main coil wire close to a ground and tap power to the other terminal, when you pull the power wire off the coil will fire.

You just need to tap the power wire, don't hold it too long.