Duraspark nightmare!!!

[85liftedRanger]

I bought this 85 ranger about a year ago and no one can figure this out. the truck will crank but i have no spark. i have power goin into the icm but no power going to the dist. wth? can someone please help me. i have replaced the dist., cap, rotor, icm, coil, plugs, ign switch, and still no spark!

 

[Psychopete]

What ground are you testing against? I would get a diagram and go through and make sure the icm is getting good ground and power where and when it's supposed to.

Check power at coil, too. Hook up a tach and see if the module is doing it's job at the coil (but that's not going to rule out a bad connection at the coil).

Also check for spark right out of the coil with a spark plug on the end of the wire that goes onto the middle terminal on the dist cap.

Could be anything from a crappy ground, to it not getting a start signal, to it having a wiring problem in the pigtails from the dist to module or module to coil.

 

[85liftedRanger]

Silly question, if the alternator isnt hooked up will that prevent spark on this system?

 

[strvger]

did you double check all your grounds including battery? not sure about the alternator really. you can also double check the wiring with the color schematic in the tech library perhaps. my duraspark has been no problems except for getting rid of all the unnecessary wires and plugs without cutting out the wrong one. i also got rid of all my smog junk under the hood.

 

[85liftedRanger]

From the icm none of the wires that go to the dist. have power. but there is power goin to the coil and icm. i have tried 3 diff icm's can they all be bad out of the box?

 

[strvger]

i doubt it seriously. is the voltage going in regulated or fused? they aren't being burned out when connected to power are they?

 

[kimcrwbr1]

If the battery is low it could possibly not give you a spark. Are you smelling fuel on the plugs pull one of the plugs and turn the key on. Check for power to the coil and put the plug in the coil wire and set it on a good ground. Then take a jumper wire and short the neg side of the coil to ground quick touches and the plug should fire when you touch ground. If you get spark work your way back to the TFI.

http://www.therangerstation.com/tech_library/TFI_Diagnostic.html

This will help you isolate the problem with a VOM. GL

 

[85liftedRanger]

Im not really sure how its regulated the truck is across town so i will have to check it out this weekend, the guy who is working on it says the battery is pretty much dead.

 

[mhughes165]

either a relay or ignition module, either will only take 5 minutes to changes, and it woulda have probably saved u alot of headache.

also, spend the extra couple bucks on a good module, ive had to get 3 or 4 from advance auto before i got one that worked

 

[85liftedRanger]

Really? that many? maybe that icm is my problem. i have tried 3 diff boxes