azhang253

I just encountered a very strange problem. Recently, my power-steering pump decided to come apart, the pulley and pulley-shaft separated from the rest of the pump, throwing the belt off. I didn't want the engine to overheat too badly, so I pulled over as quickly as possible (was only overheated for maybe 30 seconds).

I got it towed from the side of the highway, and I found that the shifter-cover was removed by the tow company (no idea why, the key was in the vehicle). The tow company towed it to some random location. Two days later, I drove my buddy's truck with a uHaul car dolly to retrieve my Cherokee. I started up the Heep, and drove it onto the dolly. I shut it off. I needed to adjust it, but it wouldn't start again! It kept cranking with no start. Keep in mind it was at an incline due to the dolly.

Earlier that week, I had replaced the Crankshaft Position Sensor (with new Mopar part), plug wires, cap + rotor (both brass), and new OEM ignition coil, so I doubt ignition was the issue. I fixed these to fix a very intermittent misfire. Turns out the coil was cracked all around the housing. The gas tank was 3/4 full.

Anyway, I towed it back to the shop, then I decided to try starting it again, and it started right up, no problem, no extended crank either. Then I drove it off the dolly and into the shop.

Any ideas as to why it didn't start?

fb97xj1

What year is it?

azhang253

​​​​​​​Sorry, totally forgot to include that. 1995 Jeep Cherokee Country.

Thanks!

tjwalker

Really hard to say but if you encounter it again, I'd chase it. No starts are diagnosed the same way, regardless.

1. First with a 95, you would check for spark. Remove a plug, keep it attached to the plug wire. Place the plug electrode near a good engine ground. Have a buddy crank the engine over while you watch. You are looking for a strong, BLUE, snapping spark. Yellow/orange/white indicates a weak spark.

2. If spark is good (and only if), then move onto fuel. Test fuel pressure at the fuel rail if you have access to a fuel pressure gauge. You need 31 psi to fire up the 4.0 ofo a 95 vintage. No gauge? Then introduce a very small amount of gas into the intake. If it starts this way, then you have identified a "fuel delivery" problem.

3. You also may want to check all the connections/wiring etc. on the tuneup parts that you recently replaced. When was the last time you replaced the fuel filter? Very inexpensive and easy to change on the 95 as it's right along the frame rail, drivers side.

Good luck and keep us updated!

azhang253

Sounds good, I'll update this thread if it happens again. I think, just to be sure, I'm going to clean my NSS.
I did double check all connections, but only after I got the Jeep into a garage. They all seemed fine to me. I hit the shrader valve and there was fuel pressure, not sure if 31PSI. I didn't have my gauge with me at the time.

tjwalker

If the engine turned over well but did not actually fire/start, the NSS would not be involved with that issue.

If there is an NSS issue, the engine will not turn over at all.

Your issue at that time was missing either spark or fuel.

Alinoun

As of late my truck has been encountering odd beginning conditions. Typically it fires up immediately, however some of the time like 1 out of 100 beginnings it will simply keep on wrenching with no endeavor at all to fire the motor. I'll endeavor to begin it a couple of more occasions and it'll proceed to simply wrench and nothing. I'm uncertain of the condition that makes this change yet like 5 or so minutes after the fact, I'll wrench the motor and it fires straight up no issue. ​​​​​​For model: I did some cruising through the neighborhood a short while back, presumably turned on/off my truck like multiple times without issue, I halted at a store on my route home for like 10 minutes, jumped back in my truck and Bam, simply wrenches the motor, no endeavor to fire. I attempt a couple of more occasions without progress.

cruiser54

Does this occur when the vehicle has been driven and then parked?
Or, does it do it on an initial cold start also?