I recently bought what I thought was a great deal (I know right) but now not so much. A 94 4wd yota w/3vze. It ran really rough and after a compression check and a little more mech pokin' around we yanked the heads and had them redone. We found several issues but all and all nothing unexpected. After putting the engine back together, we attempted to crank it up. It turned beautifully but no start.
We then rechecked our work ensuring that timing was correct, everything plugged in/connected, and that we had fuel.
When we checked spark, we found that we had it from the coil to the distributor, but not out to the plugs.
I have read a bunch of posts about similiar problems, but for some reason no one ever comes back to give their solutions.

I have the FSM and have replaced the ignitor, distributor, ECU, and some other parts. Any assistance would be greatly appreciated.

Pops

 

Plugs and wires? You sure you put in a good distributor?

 

first thing I would do is go buy a spark tester at auto parts store for $5, looks like half a spark plug with a clip on it to ground it. THen test out your ignition coil primary and secondary.

 

We replaced the distributor, ignitor, cap, rotor, ECU and other associated parts, we get a healthy spark from the coil, but nothing from any plug wire. I have done the "Tap" test and ohm'd everything out. I will give this one more try then I am taking it to a shop.

 

Did you index the dist correctly? It could be throwing the spark when the button is between ports.

Other than that, chase the spark a little more unorthodox. Remove the cap and use a good ground wire (not one from the truck, use a heavy gauge wire attached to a ground) (oh, use insulated pliers to hold the wire please) to check the spark from the center of the cap on the underside. Basically making sure the spark is traveling through the cap.

Reattach the cap and use the same good ground wire to check all the plug wire ports, one at a time.

BTW, have you checked the battery charge? You might just have a weak as hell spark that is being ate up with resistance, afterall you did just have the engine torn down for a while.

Hope this helps

 

That doesn't make sense. If you are getting spark from the coil, then the primary is good and the distributor is signaling it to fire. If it just isn't coming though the cap and across the rotor to teh plug wires then the only thing I can think is that the cap isn't contacting the rotor. The little spring contact inside the cap in the center, maybe it popped out. Or maybe they gave you the wrong rotor?? I did have an issue before where I replaced I think it was just the cap, and got weak spark because the manufacturer made it slightly different. Worked fine with their cap like it was amatched set.

 

Mr Peepers,

I completely agree...that is why it is such an issue. I have read several other threads with the same issue but they never post what the fix was. If I figure it out (or we all figure it out) I will post what the fix was no matter how riduculously simple it may be.

I suspect that there might be a grounding issue somewhere or an inappropriate signal coming from the computer. I will keep checking.

 

Sportsmanphil<

We will give that a shot this weekend...

 

A little trick, if you are 'leaking' the energy from your coil, it can sometimes be found with a little soapy water.

Put some soapy water in a spray bottle and while the engine is running, spray down the coil, coil wire, dist cap and plug wires. If the energy is leaking to ground, the water will 'help' it and you will not only see the spark but hear it all of a sudden.

Its a shot in the dark but give it a try.

 

Hmm, what I would probably do at this point is go somewhere with a good return policy like Pep Boys and buy a coil and new plug and coil wire. Replace these, but do NOT mount the coil, let it rest on some cardboard or something out of the way. Then try it.

 

It ended up being the coil after all that. It had spark but not enough. Of course now we have a code 12 on the ECU and need to check the wiring. It runs but won't pass smog with the code.