OK i need help I bought my son a 89 ford ranger 4X4 with the 2.3 litter motor,It has ran great until the other day when it just died.I did some trouble shooting and found that I have no spark coming form the coil on the drivers side of the motor,I have replaced everything I could thing of new coil,ICM,ECM,crankshaft sensor.I checked fuses and power going to the coil all ok.Any new advise would be great.

 

So in other words you are just swapping parts randomly. Do you have an electrical tester? If so, find out which circuits are getting power, and which ones aren't. Find out what is working, so you know where to start. Is your system using the dual plug setup with coil packs? Or do you have a distributor?

 

Yes I have a volt meter.I have a Fluke 87 and a 73.I have power going to the coils,I had the ICM tested at auto zone it tested ok but as you know they sometimes test good but are bad.I had a set of coils on hand so I just swaped it out also I switched the coil on the right with the coil on the left to see if it would fire did not make a difference. I was told there was no way to test the crank shaft position sensor and Ford wanted $175.00 to check the ECU plus the tow bill to get it to them a new ECU was $109 at this point I thought it had to be either the ECU or the sensor I bought both but the truck still wont run

 

Is the ECM ground still connected at the battery?

 

Yes the ECM is grounded.

 

Here is a way to test the coil. If you connect the coil to a 12v source, and leave the ground disconnected, and connect the coil wire to a grounded spark plug, then touch the coils primary ground, every time it touches, you should get a spark. A coil creates spark by the build or collapse of a magnetic field. This building or collapsing induces a current in the secondary coil. The primary side has a few windings, which the secondary coil have many windings, so this causes the voltage int eh secondary coil to be much higher than the primary winding. The voltage is great enough that it will jump a spark gap. So if you present, and then repeated interrupt the coils power supply, it should spark. If it produces bright blue sparks, the coil is working properly, and it is not getting a signal to turn on an off. The on/off cycle is controlled by the ignition control module (ICM) which in turn gets its signal from the PIP or crank signal. If you have a distributor based setup, which you never clarified for me if you did or not, the PIP signal comes from within the distributor. This signal can be tested with either a scope or an LED strobe light. It should flash as the distributor turns. If you have a DIS (Distributorless Ignition System) then the ignition module gets its trigger signal not from the cam sensor, but from its own crank sensor. The signal generated must be tested with a scope, and strobe light is not a conclusive test. If this signal is absent, then the ICM will not work.

Another area to consider, is the ICM getting a good ground. Years of corrosion and grease can impair the grounds, and a poor ground can cause all sorts of grief. I would not think the computer to be that likely a suspect, because both the DIS and TFI are designed to be standalone ignition systems, meaning that they can operate and continue to produce spark without input from the computer. The computer merely sends these modules a signal that alters timing. So without that signal, the modules will default to 10 degrees BTC.

 

If I understand you explanation, you have power all through the system except from the coil to the plug. Is that correct?

If so, try to replace the wire from the coil to the plug on cyl. number 2 and see if the plug fires.

Let us know how you get along.

 

I had the same problem, it ended up being the pigtail going to the top of the icm. If it helps, cool. If not, its a fairly wavy check with a hanes manual.

 

I've had a bad TFI pigtail as well. Tracking a broken wire can be a little harder, but saves money over swapping parts. All it takes is checking the continuity on the wires.