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1990 isuzu trooper

Cranks but won’t start. I’m getting fuel but no spark. Coil is good, so are the spark plugs and distributor. Help

Perhaps you have a faulty ignition system?

Thanks for the response, but which part? Maybe the ignitor?

I’ll assume the distributor is driven by the camshaft. With the distributor cap off, crank the engine and observe the distributor rotor. Does the rotor rotate?
You want to know about the ignitor? Test it: http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c15280062175

What motor is it?

it’s a 2.8L V6

Okay, so the 2.8 is a GM built engine (the same as in the same era s-10 pickups) that has an ignition module instead of an igniter (although the part does much the same thing). Unfortunately, there’s not an easy way to test it, so it’s sort of a process of elimination-- if everything else checks out good you change it.

Having a paper manual is nice, but you can use the manual link HelloKit gave you. You will also need a decent Volt/Ohm meter. Assuming the distributor is turning you need to check the ignition coil primary and secondary resistance and the pickup coil. If those seem to check out fine, change the ignition module.

This also assumes that the cap and rotor and spark plug wires are in good shape, so if those haven’t changed in a while it might be a good time to do a tune up as well. A sufficiently worn cap and rotor can cause a no-spark situation, so you could also check for spark from the coil before you do anything else.

I would not bet it is your problem, but why have you not checked the plug wires?

Thanks a lot for your reply. I’ve got a manual on the way and hopefully will figure this out soon.

OK, back to this thread. I’ve headed all your advice and everything mentioned above has checked out good, except the ignition module. So, i’ve replaced it. I’m now getting plenty of spark, but it still won’t start. Now i’m not getting any fuel! It’s like I change this one part and it affects another. Making me think it’s still electrical,maybe some part of the computer system? This engine has a throttle boby injector unit on it. Any ideas? It seems odd to me that something (fuel pump,filter,lines…)or something would go bad the moment I change that module. It was getting fuel yesterday morning, just before I changed the module out. Puzzled.

Check your fuses. There’s a very good chance you popped the ECM fuse while you were checking the pickup coil.

On these cars, the ignition system is mostly separate from the fuel system, so if the computer isn’t getting power you’ll have spark but no fuel. But it does have a rudimentary spark control function, so you can pretty easily pop that fuse while poking around the ignition system.