Have Ford Questions? Ask a Mechanic for Answers ASAP
Hello and welcome! My name is ***** ***** I can assist you with your question. Does the check engine light come on with the key on? Does it og off while cranking? Both are very important. Both the yellow wires going into the ignition switch should have power at all times. Then the red/light green wire should have power leaking the switch with the key in the "run" position.
You can also run a few voltage checks on the system. There should be 5 volts going to the TPS with the key on and there should be battery voltage on the red wire going to the idle air control motor with the key on.
Please run these checks/tests and post back with your findings. I do work all day today but will be back on line later tonight. I will be looking forward to your reply!
Thank you for checking these for me. Do you know if the engine has injector pulse while cranking?
Ok, no problem. Lets check the power going to the ignition coil and ignition module. Backprobe the Dark Blue wire at the ICM connection and check the circuit for voltage. It should indicate greater than 9.0 volts or less than 1.0 volt. If the voltage is high, tap it to ground simulating an RPM signal and listen for the fuel injectors to trigger, the fuel pump relay to activate, and the coil to trigger indicating a defective distributor pickup coil. If the voltage of the circuit is low, induce power into the circuit through a standard 12-volt test light and check for the same activity from the fuel injectors, coil, and pump relay, indicating a defective pickup coil. If the described activity does not occur when the circuit is tapped to ground or power through the test light, check the DB wire for a short to ground in the harness between the ICM and the PCM connections.
Here is a wiring diagram of this circuit.
Hello and sorry for the delay! Did you say there is fuel pressure when cranking? Does the engine have spark if you pull the spout connector and restest for spark?
I suspect you may have a wiring issue going to or coming from the distributor. Check for a ground signal trigger going to the ignition coil on the (Dark Green/Yellow (DG/YL) wire) with a test light connected to battery positive and check for a trigger signal when cranking. If no trigger signal is present, check the same circuit for a trigger signal at the Ignition Control Module (ICM) with the ICM and coil connected.
I do work again until late tonight. I will be on line after work and tomorrow morning before work. I will be looking forward to your reply!
So your saying that the spout connector was disconnected during this test?
Ok, if there is no signal coming from the ICM, then the new ICM is either bad or there is a wiring issue going to the ICM or coming from the ICM. Be sure to inspect the wiring harness very close and check for a good ground going into the ICM.
Does this ignition module get held in place by a few screws?
Well, I got some bad news. I am all out of ideas. I will leave this question open for other experts. Good luck!
Hello, new expert here, I've got a few things for us to run through to check the ignition system. I will pst them below.
Also checkthe wiring around the coil, ifit's in convulted tubing, which it should be remove it and examine the wires closely. The tubing being on them was actually due to a service bulletin from ford and they may have rubbed some on the coil bracket before the bulletin was carried out.
Let me know what you find and we can work further.
Thanks,didall the voltage andcontinuity tests between the TFI plug and ecm show good as well?
Run through those checksI posted earlier, they should narrow it down to the culprit.