Thanks Subford... your posts from previous threads have been most helpful; you are a huge asset to FTE. Not sure if the PIP is more likely to fail all at once or if there's any significance to it, but about a month ago my truck wouldn't start one day and then it did the next day. This time I drove it around town one day and the next day it wouldn't start but still won't start that's why it was time to start troubleshooting. Is it possible for the pip sensor to get weak and work one day and not the next?
Most of the time they will not start. There are also ones that do start and run for a while then the engine will quit after a few miles. It will not restart for a while then the engine will start back up and then quit again after a few more miles. I have not heard of one going bad the way you described.
It sounds like you have checked everything else but make sure the plug that plugs on to the coil is good as I have that plug cause this problem also. Check with a test light that you have power on both small wires on the plug with the key on.
I would go ahead and replace the Black ICM with another Black ICM. Make sure they do not sell you a Gray one.
If that does not do it then itwould have to be wiring. Either you have a wire shorting to ground or an open wire.
I hope you are leaving the PCM Computer unplugged during all of these test for spark.
It is also possible that they sold you a bad distributor. One poster said he had to take three or four back before he got a good one.
Here are diagrams of your system "H" if you need them.
But the ICM tested good... also does the PCM = ECM ? The first time I checked for spark it was plugged in but then subsequent test I had it unplugged. I should see spark at my #1 plug when cranking the engine and shorting case to ground right? Thanks again.
The ICM's are hard to test. They can pass a test and fail on a vehicle.
However, more often than not...the vehicle will start but once it gets hot it'll loose spark.
Yes you should, but that isn't the best way to do it. Go ahead and pick up a spark checker next time you're at the auto parts store. They're cheap and are a reliable way to make sure you have no spark.
I've seen a lot of people chase problems for a long time based on false initial information.
ECM was used on our trucks in the late 1970's to the mid 1980's. Then we had the EEC Computer from the late 1980;s through some early 1990's trucks. The PCM Computer started about 1990 in some trucks and all by about 1993. The PCM is still used today on new truck as far as I know.
All Three had different jobs to do and that is why they had different names.
Emission Control Module (ECM): The module that controls emissions.
Electronic Engine Control (EEC): The system that provides electronic control of engine operation plus also controls emissions.
Powertrain Control Module (PCM): The module that controls the EEC system plus Transmission Control.
As MustangGT221 said yes you should have spark but it is best to use a spark tester.
The problem was the PIP/Distributor. My other problem is when I swapped out the coil with a "known good one" it apparently wasn't. I left it in there and swapped the dist. and it still did not work. I unplugged the coil connector and ran a wire from the red lead to ground through a 5amp fuse and it blew so I know I had power at the coil and after wiring checked good decided to put the original coil back in there and it started right up.
Just going by the FORD factory shop manuals and that is what they say.
You must have a different source.
It can be a PITA. The information Ford used in-house...or what might be in a printed manual...is not mainstream.
I've never seen anyone differentiate between a 'pcm' and 'ecm'....same thing...refers to the engines computer. The main difference only comes in that later vehicles used the computer to shift the tranny where early ones did not. That may be the use for the change in term...but regardless...they're interchangeable amongst the general public. PCM and ECM are refering to the vehicles engine management computer. Regardless of if that computer shifts the transmission or not, it's still an engine management computer. It's not a totally different piece of equipment.
I'd still like to know what they really are refering to when they say 'emissions module'. Our trucks don't have that...and if they do...than they're refering to something other than a computer box such as the ECM and that is just confusing.
BTW, there are better ways to check for power at the coil! Use a test light or voltmeter! Voltage spikes in an EFI system are your enemy!