MJ studdenly won't start...please help.

[Disturbed]

OK I will start by saying this happened this morning when I was leaving for work, I didnt have time to mess with it so I just jumped in my ZJ and headed for work. I will tell you what I know and hopefully someone can give me idea on where to start, I don't have alot of time and I need the truck running.

 

Truck ran fine last night and has not given me issues for quite a while. 1988 with a 4.0 (renix), manual trans. It has been running great, consistanly getting over 18mpg, just filled the tank yesterday. Every now and then it would seem to stall but fire immediately and keep running, this happened maybe 3 times and in the last 5 months. This morning it would not start. It cranks over fine and plenty fast. I can hear the fuel pump run when the key is cycled, but no fire. It is odd because everything was fine, so it seemed, last night when I got home from work, this morning, no love.

 

I will start by check fuel pressure and spark later tonight but I was hoping that someone here could give me some common issues that could cause this to check out. I have 1 year old twins and very little time to mess with this and help you could give me would be greatly appreciated it. I will update this thread when I have more details, fuel, spark, etc. I have the Renix manual that I downloaded off of this website which will probably be a great help.

 

Any deas?

 

Any ideas?

[vaquaro]

CPS -crank sensor , easy fix :thumbsup:

[HOrnbrod]

:agree: But first try unplugging the connector and cleaning it up with some contact cleaner. Could be just corrosion if you're lucky. :D

[Disturbed]

Well since we are 2 for 2 with the CPS and this site seems to be very knowledgeable I will pick one up before I go home tonight, I checked online and they are only about $30. Is a CPS failure on these trucks common? Should I have one in my spares for the truck and carry it at all times?

[beaterheep]

mine did the same thing, i set a prybar on the cps and just barely tapped it with my hand, that was 3 weeks ago and its been perfect ever since, think mabye it was just corroded...

[2360]

I'd check your fuel filter, might be plugged up.

 

About a month ago my truck just died driving home from work.

It started for a few sputters and died again. Did this several times.

I was figuring the fuel pump, got under the fuel tank and banged on it hoping to give it enough life to get home.

Truck started after a few tries sputtered a bit but then off I went home without incident.

Next day or so I pulled the fuel filter and all kind of orangee yuck came out. Put it back in haven't had a problem since.

 

I wouldn't want to change a CPS, doesn't look like fun. I'm a bit worried my CPS will go some day with 502,000 km's on it.

[Lloyd]

Certainly try the fuel down the throttle body test. And the cross over the ballast resistor test, Two ideas that the great people in CC gave me that directed me to an inexpensive fix of my problem. And once again, Thank You to those people who helped me solve my issue. Whoa, 1 year old twins! I bet you are strapped for time and money. Hope you get it fixed.

[Disturbed]

It was the CPS, well sort of. I started under the hood to unplug the sensor and check for corrosion. When I did I noticed the wire to the sensor was laying again the exhaust manifold. Pulled the wiring away from the manifold, hopped in the truck and it started right up. Looks like the wiring had melted and was shorted against the manifold. For a temp fix I wraped up the melted section with electrical tape and wire tied the wiring away from the manifold.

 

I have a CPS and I'll swap it out in the near future as soon as I can move the CNC project I am working on and use my lift. Thanks so much for the help. I just have so much going on right now and very little time.

[Disturbed]

Whoa, 1 year old twins! I bet you are strapped for time and money. Hope you get it fixed.

 

Money actually isnt that bad, my wife works at the daycare center so we get a VERY good discount.

 

 

Time is the biggest problem, but I have too many project going at once so that is my fault. Kids go to bed between 7:30 and 8:00, I am usually headed to my shop by 9-10 and the I work until I am tired. Usually midnight or so, but sometimes 2 or 3am if I get into something and loose track of time. Currently I am working on our boat, the boat trailer needs some welding done on it, building a stand for my smoker, dialing in my CNC plasma table, and building a water table for the CNC Plasma. That's just what is currently in progress, not what is sitting around waiting for my attention, but the "too many projects" syndromn is a problem I had way before the kids were born.