My Trooper randomly dies on straight, smooth road. Just ups and dies. It is hard to start also. I have to cycle the key on and off until the CEL comes on, and THEN the truck will start up great.

I did notice that performance does lag. Sometimes I can go up a hill normal, also im shifting all the way to 3rd gear to get up a hill and still losing power.

Engine grounds are checked and fine, new battery cables and terminals. Thought it was the ignition module, switched it out, nothing.

Now when I am cycling the key sometimes I hear the engine bump, almost like the start engages just a tiny bit. This is without me putting the key in the START position.

Any thoughts? This thing is driving me nuts!

Try some of the common fixes for this problem in this post.
http://www.4x4wire.com/forums/showflat.php?Cat=&Board=UBB86&Number=811748

Whatever you tried and didn't work, let us know.

All spark plugs are in good working order. All seated, no holes in insulation. And yes my tire pressure is ok (:o It was on the list!)

Air filter is new. I checked over vaccum hoses as well as manifold leaks, everything is good. PCV Valve is new, I took it out and is still good. Complete air system (Intake) Was dismantled and cleaned; that is all clear.

Cap and rotor are brand new. Maybe 200 miles on them, did not help the problem any. Id like to check the fuel pump relay..In the fuse box?

MAF Sensor was swapped with another, same issue.

Some problems started while I pulled my ECU to Herculine my interior. The Trooper hasnt been the same sense. I do run an MSD 6A box w/ Tach adapter. I also have switched out Ignition modules, and bypassed the MSD.

Check your ECM connections. Drag test the terminals.

CHECK THE IGN SW ITSELF ,THEY HAVE BEEN KNOW TO WORK LOOSE ON THE BACK WHERE ALL THE WIRES ARE SOLDERD ON, AND ALLSO CHECK THE MAIN RELAY IN THE FUSE BOX THE BROWN ONE , WITH THE ENG IDELING GIVE THE RELAY A SHARP RAP WITH YOUR KNUCKLE AND SEE IF THE ENG SPUTTERS , THIS IS THE MAIN POWER RELAY TO THE ECM AND IT MAY BE GETTING TIME TO REPLACE IT , IF THE CEL GOES OFF SO DOES THE ENG , IF THE LITE DOES NOT COME ON WITH THE KEY IN THE ON POSITION THE ENG WILL NOT START . JERRY

( for future reference: does this mean even if the bulb is blown. . .that is, the only reason the CEL light isn't coming on is because the bulb is kaput and therefore that circuit isn't complete. . .?

thanks )

I hope none of the isuzu engineers are reading that they might be very offended. <img src="/forums/images/graemlins/lol.gif" alt="" /> Can't drive my troop I burnt the check engien light!! Might need a trail spare bulb!!

just kidding man, no, what he means is that the cel not coming on is often an indicator of a bigger problem (the ecm not getting powered up), and subsequently the engine will never start.

I was hoping you would reply Jerry! Thanks for everyone else also.

Well I replaced that relay and it has worked great so far. Hopefully that is it..I will drive it for a couple days and see where we sit.

Be careful here, you might be looking at two problems. If it seems the relay fixed it, that's good, but keep listening for this, cuz that ignition switch could be goin' flaky on ya.

they'd be offended? you mean those engineers that designed it so the dash lights up like a vegas casino when the alternator is on the fritz? they'd be offended? yeh, right.

or do you mean those engineers that designed it so the automatic transmission does weird and unpredictable things simply because the charging system isn't producting volts in a rather narrow parameter? or the ones that designed it so there's no indicator what the problem is. they'd be offended? yeh, right.



i know there is some humor there, but this is a real question on my part. i understand the ecm/CEL connection. i'm just wanting to be assured by "mr.isuzu"JLEMOND hisself that the bulb itself is not part of the circuit in this case...

<img src="/forums/images/graemlins/cheers.gif" alt="" />