No Fire~Replaced Everything

[kscycler]

I have a 1986 2.9L sweetheart that's dead in the driveway. Drove to the train station, left her for a day, came back and she wouldn't start. Cranked fine but wouldn't light off. Came back the next day and she fired right up. Drove her home and she hasn't started since.

I've replaced the ignition control module (ICM), coil, distributor, distributor cap, rotor, and ignition switch and still no fire. There's 12v power to the coil, so I can't see why there is no fire. And, there doesn't seem to be any fuel pressure at the rail. Is the fuel pump somehow interconnected or am I just imagining things.

I've been to a mechanic only once in 34 years, and have replaced/fixed everything on all my vehicles and kids cars, but this one has me stumped. Any help anyone can suggest would surely be appreciated.

 

[madmax]

if the fuel pump isnt running the plugs can spark till they melt, they cant ignite what simply isnt there. try removing one plug wire and putting it on an extra plug with the threads of the plug connected to ground. if it sparks when you crank it over then check your fuel pressure again. If youve got no fuel pressure check the voltage at the pump. If you are getting pressure you should make sure the injectors are getting a signal, how that is done though I don't know. If the pump has power but your not getting fuel then theres either a blockage in the line or filter or the pump is simply dead.

 

[kscycler]

if the fuel pump isnt running the plugs can spark till they melt, they cant ignite what simply isnt there. try removing one plug wire and putting it on an extra plug with the threads of the plug connected to ground. if it sparks when you crank it over then check your fuel pressure again. If youve got no fuel pressure check the voltage at the pump. If you are getting pressure you should make sure the injectors are getting a signal, how that is done though I don't know. If the pump has power but your not getting fuel then theres either a blockage in the line or filter or the pump is simply dead.

 

[kscycler]

Thanks for the note. The problem I have is no fire. No spark at the spark plugs. Maybe I wrote it wrong, but I can't figure out why there is no fire to the plugs. The fuel comment was secondary and I only wrote about it to see if somehow the fuel system could keep the plugs from firing. I think I need to solve the "no fire" situation first, as I assume there will be fuel pressure if there's fire. Thoughts?

 

[yusuebronko2_86]

distributor, coil, cap, rotor, plugs, and wires, as well as control module on the back of the distributor have been replaced, right?

if all those parts are in good working order (which they should be if they're new) and there's power TO the parts, check power FROM.

make sure ALL you grounds are in good shape, no corrosion. that includes that funny little wire from the battery that somehow makes its way into the main ECM harness. that's the one that gives the ground to the computer to tell the injectors when to fire. that's instant no-go if not connected or intermittent (kinda grounded).

check the ground from the coil, make sure the ground to the engine is in good shape.

if all are in good shape, proceed to check your relays. they're a real pain in the butt, so I recommend getting somebody who knows their way around relays to help you. you may need to replace a couple, and they're all different inside. the relays are located along the passenger side fender inner, those little black or brown boxes with hundreds of wires going every which way.

hopefully this sheds some light on your horse. i know first hand how the '86s can be a real pain. good luck!

 

[kscycler]

Well, I figured it out. After realizing that I had no fuel pressure, I wondered how fuel pressure and no fire could be related. And your comment about relays triggered the solution. The EEC relay provides power to the computer brain which gives power to fire and to turn on the fuel pumps. There was power to the relay, but no power coming from the relay. After installing a jumper across the contacts, the fuel pumps came to life and the beast fired up!. Yeah! Now, I have a clogged injector or a bad plug or a bad wire, and that's a bit unsettling as the engine ran fine before, but I think I can solve that with a bit of injector cleaner and a new set of plugs/wires.

So, put this one in your thinking cap. Fuel and fire are related, by means of power to the EEC computer through the relay. Thanks for all the help...