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The title sums up my problem, no spark at the plugs. My truck is an '87 with the 2.3 and 5-speed.
My truck wouldn't start today so I checked a few things out to narrow down the problem. First I checked the fuel pressure, it was strong at 40 psi. Next I checked for spark at the ignition coil, it was ok. Finally I checked for spark at the spark plugs and there was none. I pulled off the distributor cap and rotor to clean them on the off chance it might be a moisture problem. Didn't do any good.
The plugs, cap and rotor are pretty new. The wires aren't but they checked out recently with a resistance test. The ignition module and coil are also both fairly new. The distributor itself is the original. Anyone know what else I should check out to find my problem?
Could this be a distributor related problem? Is there any way to test the distributor other than looking for spark? Any ideas or things I could try would be greatly appreciated.
As far as observing the rotor, will I just see it moving in its circle? What exactly would I be looking for. All the truck has done since the last time I drove it is sit for about two weeks. The timing should be ok, but it couldn't hurt to check again.
My money is on the TFI module as well. Of course you want to check for voltage at the coil and TFI module just to make sure you're not needlessly replacing parts.
Here is an article I use to test TFI modules that I come across.
If you ever go digging through junkyards, pick up a few spare TFI modules while you're there. Test them out and toss a good one in the glovebox along with a TFI module wrench. If your truck just starts running rough or won't start, it's better than having to call a tow.
So I finally had time to mess with checking out the TFI module, and had some strange results. First I took it to Autozone and had it tested. They said it was fine. Just for fun I decided to take it to O'reilly's and have them test it. Their machine said it was bad. Odd result. Since the part had a lifetime warranty (from Autozone) I made them replace it anyhow. I put in the new module but it didn't have any effect. Truck still won't start.
So if the ignition module, coil, wires, cap, rotor and plugs are all good what else could it be? I have spark coming from the coil to the distributor, but no spark from the distributor to the plugs. Any other ideas for me?
Thanks for posting that article Rockledge, very informative.
I've checked wires and they all seem ok. What is really dumbfounding me is that the coil is firing, but the plugs are not. If there were big wiring issues, if the PIP or TFI were bad, would the coil still be firing? I admit I'm not completely familiar with exactly how the ignition sytem works. Do either the PIP or TFI handle actual spark to the plugs, or do they only trigger the coil to fire? I guess just for fun I'll check the PIP for 'softness' as the article suggested. Couldn't hurt.