we have no spark at the distibutor
Asked by ippielj May 21, 2016 at 09:24 PM about the 1991 Ford F-150 XLT Lariat Extended Cab SB
Question type: Maintenance & Repair
truck died one day and would not fire up after that. we have replaced
everything except the computer and done all res, tests and voltage tests on
stuff. everything points to the pip module but its brand new as well.
where do we go from here?
17 Answers
tried 3 new different icm's, tried 2 different pip sensors, replaced ignition coil, replaced cap, rotor spark plug wires and plugs. checked eec relay , checked ignition control module. no coil switching signal there is continuity between icm and coil when we take the inut wire off the cap from the coil there is no spark when we turn the engine over.
did that, no spark whether its in or out. even unplugged the computer to see if that would change anything but still no spark.
How do you test the plug? I have tried to stick a probe in the end of the plug but the probes cannot reach the terminals? When i inspected the terminals there was slight bluing, i used electrical contact cleaner and repeatedly plugged in and unplugged the connector into the old ICM to try and clean the contacts. When testing the ICM, i have power, ground, and a signal from the PIP sensor, but nothing from the Coil switching signal. So the coil will not fire if it cannot getting the signal from the ICM. What would cause the ICM not to give a switching signal?
I have tried 3 different ICM, none give a signal. I have also done the LED test light method instead of the incandescent bulb in my test light. Would removing the red retaining clip in the ICM plug/connector allow me to remove the wires from the connector and check them? Or are they a sealed plug and require to be cut off?
we took the plug apart. it seems to be having a good connection. we cleaned the connection found continuity between this plug and the coil so its not broken somewhere inbetween. we have an led light flashing at the injector. does the coil have to be grounded or not? when we manually ground the power there at the coil it sparks. but we still have no spark at the cap
I have 3 different ignition modules, all three don't show a ignition coil switching signal. The coil has spark, i have taken a wire and it arcs when you quickly touch it.
Have u checked to make sure distributor rotor spins
I have tried two different brands of ICM, hard to believe all three including the original was faulty. But i guess what has to be done has to be done. I took an ohm meter to one right out of the box, and it failed the resistance test brand new right inside the store. Yes the distributor rotor spins, and have had everything marked to ensure top dead center when removing and installing distributor. Spout is removed to even try and get spark, unplugged the EEC to ensure that it was not the problem, i have plugged it back in, and unplugged an injector, and it is flashing with my LED test light when the motor is turned over.
The store told me it had to be plugged in to do a resistance test on the module. They did not have a module tester.
Forgot to answer a previous question, when i take my test light at the trigger wire on the coil, and then the alligator clip onto the positive post of the battery, the test light does NOT flash, but when i take a wire and quickly tap the ground it does arc on the wire. It's not getting the coil switching signal from the ICM. I've already bought $200 worth of ICM because everything is leading me back to the faulty ICM, i don't want to spend even more money on it.
PartSource sold me a "Select" brand ICM, and AutoParts Plus, sold me two different brand parts.
The other brand is "Standard". At the coil when i take a wire from the positive battery post, to the ground switching wire, with the key OFF, the led lights up, but when i turn the key into the RUN position it turns the LED turns off, and when i turn the key to the START position to turn over the motor, the LED does NOT flash. Neither at the coil, or at the ICM at the signal wire.
Here's the resistance tests i've done on the modules i have currently. Part stores are closed so i cannot take them in to get tested, and tomorrow is a holiday so i doubt any will be open tomorrow as well.
Yeah, Canada, victoria day tomorrow. From the resistances tests would you think the ICM/TFI Modules are faulty?
Standard parts comes out of specs, right from the box. Try Delphi or motorcraft (OE).
Hello. I am having the same issue with a Winnebago Lesharo class B Motorhome. What did your problem end up being? This is driving me crazy, now on my 3rd coil and 3rd ICM.