What does the ignitor do exactly?
 

I have been having problems with my 91 runner not starting when warm and has been shut off for 10 - 15 minutes.It chugs at 200 rpm's like it wants to run,but won't.Last time it did it I pulled the coil wire off of the cap to see if I was getting spark.It had an intermitent spark,1 every few seconds.I switched back to the stock coil and it still does it.What does the ignitor do?Would a bad one cause my problems?

Yes, what you are describing sounds like your Ignitor is crapping out or you have a bad ground at your ignitor or from your ignitor to your ecu. When an ignitor goes, it goes, it's usually not intermitent, we're talking no spark, there used to be a rule of thumb that when the ignitor goes, you'll get no spark and your rpm gauge won't move! Just a rule of thumb! Yeah, I'd go w/a bad ground first or bad wire, don't throw parts at your truck!
Good Luck! Let us know how ya make out!
Harry

doesnt sound like the igniter... mine died on me one day, and my truck died, i mean dead.... while i was driving.. it jsut stopped......

How can I ditch the ignitor and run a aftermarket coil without buying a 300 dollar ignition.

My truck did the same thing once. It wouldn't hold an idle when started warm. Starting it cold was fine though. Turned out to be a bad ECU.

I slapped another one in and I never had that problem since. I guess one (or more) of the resistors on the mother board crapped out or something. Good thing I had a spare ECU lying around.

The solid-state igniter signals the coil to fire the electrical voltage neccessary to jump the gap at the sparkplug which then ignites the fuel/air mixture inside the cylinders. Basically speaking, it tells the coil when to fire.

Igniters usually don't fail unless you accidentally touch one of the terminals to ground. You may want to fully diagnose the other components that could cause a warm no-start before you zero in the igniter.

Well,I guess maybe when I switched the coil and coil wire it actually did fix it,I hope.It isn't doing it now.I could have swore tested it after but the more I think about it I don't think I did.I took it to the dealer yesterday and he said his guess would be ignitor.Sometimes the heat soke will shut them down.If it does it again I'll switch ignitors.It runs great right now.No more semi rough idle either.

MSD BLASTER COILS!! haaha

I took out an msd blaster coil!Are they known for going bad?

My ignitor doesn't like me to go through big puddles. When I get water splashed up it tries to stall but the truck, but being in gear bump starts it again. But if it's not in gear it won't stall. It's only when there is load on the engine. It's pretty annoying.

I'm on my second ignitor and it does just stop like everybody else said. Starts one minute, the next it doesn't.

Well,the damn thing is still doing it.I am getting good spark now though.It must be something fuel related.I can floor it once it starts and it will rev really slow with a lot of vibration and hesitation.If I let off of the gas it will die.

Last summer driving home from school from Denver to Atlanta my igniter started to go. The engine would cough and splutter under deceleration but if I held and even throttle in would run ok. This happened going through Kansas city. I didn't turn the motor off once the rest of the way, even to fill up because i didn't think I'd get it going again. Made it all the way home and turned her off and the next morning the thing was just totally dead. It wouldn't catch at all but it got me home and that's wat counts. Those igniters are ridiculously expensive unfortunately. I think I was robbed of 400 dollars by a dealership for the part.

Could a bad knock sensor cause it to do what it's doing?I have gotten a knock sensor code 2 times in the last year but it never made a difference in how it ran.I am not getting any codes now.What (fuel related)could cause this to happen?I am ready to blow the thing up.It runs great once I get it running.

There are lots of things which cause your symptoms. Obviously bad spark is one of them. But you should also check for:

1)clean air filter
2) the intake tube between the air box and throttle body is sealed, and insure there are no vaccuum leaks on all those little hoses.
3) that the afm (air flow meter) is working within spec
4) proper timing
5) proper fuel pressure (implies clogged filter or weak pump)
6) crossed ignition wires, bad plugs, bad distributor cap & rotor, bad timing advance.

Some of this may not apply to your 91, I am not familiar with that motor.

well, it has a new pump,it will never die while driving,just after I shut it off and wait 30 minutes it will start and then die,if I wait an additional 30 minutes it will start and run great. :think: :dunno:I haven't been able to find out how to check fuel pressure.It is a 3vze v6.