Dead yet again

[iraq_vet_x2]

My jeep died for no particular reason on the road back from work today. I was going along at about 50 mph and it just shut off; no warning at all. Tried to get it started back up but it wouldn't. Tried again about 5 minutes later and it started like it always does; then I got about 100 yards down the road and it just quit again. It's now sitting on the side of the road... maybe someone will steal it and ease my pain.

 

[kmack]

Have you checked for spark? Bring a tester with you. Have you replaced the crank sensor yet? What have you replaced/checked since the problem started?

 

[elevatorman]

check for obstructed exhaust pipe-could have gotten crushed or collapsed internally.

 

[iraq_vet_x2]

Ok, I just got my jeep towed back to the house with a friend of mine and got to do some troubleshooting before the rain started.
I put my timing light on my coil to distro wire and got no blink. So, to answer your question, no, I'm not getting spark. I pulled the pigtail off the coil and put my multimeter on them. 0 volts with the key off, then 11ish volts with the key on and trying to crank.
I recently did the TFI upgrade and it's been running great ever since. Common sense would tell us that the coil is bad and I just need to replace it. The thing is, I bought it new from the store not too long ago. i put the old coil i had back on to see if that would work but it didn't either. The thing that bothers me about that is my plugs are gapped for the upgrade and i don't know if the old coil would have had enough power to overcome that gap.

The other thing i don't know is how much power am I supposed to be getting at that pigtail? Is 11ish volts enough to run the coil?

 

[HiHood]

Have you checked for spark? Bring a tester with you. Have you replaced the crank sensor yet? What have you replaced/checked since the problem started?

SPEED (crank) SENSOR is what I'ld check first.

 

[iraq_vet_x2]

I don't think I have a speed / crank sensor; I have a 4.2 L carb engine, no fuel injection. If I'm wrong, let me know where I can find it in the Jeep, and I'll go check it.

 

[kmack]

Crank sensor is on the trans. bell housing...drivers side top. 2 bolts hold it in place...a little tight to get to.

 

[iraq_vet_x2]

No, there's nothing there. Ya'll see that I have an 89 4.2 L right?

 

[buckshot500]

I don't think you have that sensor either. What shape is your ECU in? Is it a real duraspark box?
I try to find real ones on every trip to the junkyard, (since they don't make them anymore) only found one so far in an f-250.
Not sure how to test that puppy either.

Also, when you say "TFI" you really mean the TeamRush upgrade, right?

 

[iraq_vet_x2]

I think my ECU is in good shape, but then again...it is a Jeep.

Yes, I am talking about the TeamRush upgrade.

 

[buckshot500]

I think my ECU is in good shape, but then again...it is a Jeep.

Yes, I am talking about the TeamRush upgrade.

I meant to say ECM box, it's on the driver's front fender, below the reservoirs. If it's fairly new & from a big box parts house, it may not be made very well (China).

The real Duraspark ECM's are made better, & you should look for one at the junkyards.

If you've done the HEI module deal, then it shouldn't be the problem.

The TeamRush upgrade is done, to give you a greater distance between the cap terminals reducing the chance of crossfire greatly.

The Idea is to get a hotter spark, so you can burn the extra fuel delivered by the MC2100 or the weber.

So using the original type coil, defeats the purpose of all this.

What you want to do, is use the E-core coil. It puts out a much hotter spark that would overwhelm the original distributor cap.

This is the reason for gapping the plugs wider.

No sense buying one new, when they are cheap as dirt at the junkyard. I got mine out of a 1986 Ford escort, but they came in many vehicles. My 1990 Aerostar has one.

Kind of tough to see it here, but I used the escort mounting bracket. It's holes line up with the ones in the 4.2L block, just had to trim off the unwanted part of the bracket.

 

[iraq_vet_x2]

I think I worded this poorly...I did put an E-coil in and I'm thinking that is what's gone bad. I put the old coil back in, for trouble shooting purposes, just to see if the engine would at least turn over for me...but it didn't. Another part of my concern was if that, as a troubleshooting procedure, was a valid thing to do since the 45 gaps were still in the plugs. Here's a pic of my E92 I bolted to the passenger side of the engine bay.

 

[SteelHeadz]

There are 3 wires from the Ignition module to the distributor, are all 3 properly hooked up to their respective terminals?..There are also 3 wires going to the Ignition module; White(Starter solenoid),Dark green (Coil), Red with a tracer(Coil and ignition switch).Somewhere between the ignition module to the ignition switch on this red with a tracer, is a resistor wire. Check it for continuity. Most of the time, after upgrading the coil, this resistor wire will burn and or break internally.

 

[iraq_vet_x2]

Okay, is this the wire you're talking about?

 

[SteelHeadz]

Yes.

 

[defmornahan]

I think I worded this poorly...I did put an E-coil in and I'm thinking that is what's gone bad. I put the old coil back in, for trouble shooting purposes, just to see if the engine would at least turn over for me...but it didn't. Another part of my concern was if that, as a troubleshooting procedure, was a valid thing to do since the 45 gaps were still in the plugs. Here's a pic of my E92 I bolted to the passenger side of the engine bay.

Holy crap, that looks exactly like what I did to bolt that coil on.

Anyway, I think I PMed this to you earlier, but if you've only got 11ish volts and are "trying to crank"--does it sound any weaker than usual? Because it sounds like that battery is nearly dead. I'd check the battery and alternator.

 

[Rubicon Rich]

You can also do a starter draw test and see if it goes below 9 1/2 volts. If it does, it's the battery. Take an amp reading during start-up and see if it's within specs. If it's not, the problem is within the starter.
While you're at it.....take a test light and connect it between the ground battery terminal and the battery ground cable. There should be no strong light emitted. If there is, you got a draw. To easily find the draw, keep the test light connected as I said and let another person hold it in position. You then go to the fuse box and take one fuse out at a time. When the light in the test light goes out...you found the faulty circuit. Then put the fuse back in and shake the wires in that circuit to make the test light blink.
When that happens, your hand will be with in inches of the problem. Any short in a car will produce static. Get a portable radio with a whip attenna. Tune it to a clear FM station and run the whip around the vehicle. When you hear static, there will be the problem area. Fine tune it by using the whip to produce the most static and you'll be within six inches of the fault.
If you need a test light...make one from a 12V light socket with the wires still attached....it will work fine.

 

[iraq_vet_x2]

Mikey, I just did the continuity test on the resistor wire we've been talking about and my multimeter beeped at me, it's still intact. Anyother problems you can think of.

Paul, to answer your question, no, the battery never sounded weak when I was trying to start it back up. I know it's good to go.

Rich, I love your troubleshooting techniques. I may try to pass them off as my own some day, HA!

I'm going to keep testing wires but, if anyone has any further ideas...please post.

 

[kmack]

Take a test light...ground to the battery... you should have 2 terminals at the coil...key on you should have power(battery voltage) at both terminals...then crank the engine over...one terminal will be lit constantly...the other should blink...if it blinks you have a bad coil(secondary windings) if not you need to look closer at the pick-up in the distributor etc. At least you'll know if the coil is getting a pulse and you can narrow your diagnostics from there. Good Luck.

 

[iraq_vet_x2]

Ken, that's a great piece of informantion, I'll do that and let ya'll know how it comes out.