94 f150 problems
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94 f150 problems
I have a 94 f150 with a 5.0 that is starting to act up. This is the first problem ive ever had with this truck.
The truck is cutting off on me with no warning. Some times it will crank right back up and other times it want but come back later and it cranks. Its been doing this for a week or so now. It doesn't get sluggish or anything it just dies with the blink of an eye.
Whats wrong?
The truck is cutting off on me with no warning. Some times it will crank right back up and other times it want but come back later and it cranks. Its been doing this for a week or so now. It doesn't get sluggish or anything it just dies with the blink of an eye.
Whats wrong?
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Had the ignition module tested today and it tested good. Ill check the PIP in the morning. Is there anything in particular I should look for to see if its ok.
I do know that when it want crank that im not getting fire between the ignition coil and the distributor. Would this be because the PIP is not picking it up or is trying to put a gap between the two to check for spark not a good way to test? By the way its a new ignition coil.
I do know that when it want crank that im not getting fire between the ignition coil and the distributor. Would this be because the PIP is not picking it up or is trying to put a gap between the two to check for spark not a good way to test? By the way its a new ignition coil.
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Joined: Oct 2005
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From: Kentucky
The PIP is what starts the process to trigger the ICM which in turn fires the coil. With the engine running the PCM comes into play to advance/retard the spark. There is no good way to test for a bad PIP other than knowing the coil and ICM are good that I know of.
When you have a no spark condition you could try momentarily grounding the negative side of the coil. This is simulating a command to fire the coil, you should see a spark. Another telltale sign of a bad PIP is no RPM reading on the tach during cranking. I have also used a DVM that also measures frequency or duty cycle. Attach the meter to the negative side of the coil and a good ground. Turn the engine over with the key, see if you get a frequency read out or if using duty cycle it should read 50%.
The PIP sensor can be very heat sensitive, more so than the ICM.
When you have a no spark condition you could try momentarily grounding the negative side of the coil. This is simulating a command to fire the coil, you should see a spark. Another telltale sign of a bad PIP is no RPM reading on the tach during cranking. I have also used a DVM that also measures frequency or duty cycle. Attach the meter to the negative side of the coil and a good ground. Turn the engine over with the key, see if you get a frequency read out or if using duty cycle it should read 50%.
The PIP sensor can be very heat sensitive, more so than the ICM.
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