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Does the speedometer fluctuate as well? many times it can be a bad RABS module pulling down the VSS signal. I do recall reading a post from subford where the VSS output should be in the 3.5 -4.0 volt range when the speedometer indicates ~30 MPH. That was from memory, I suggest you search a few of his posts.
That would be the best place to start. If the signal is low remove the connector from the RABS, see if the signal level increases. If it does then you know it's not a VSS or PSOM caused problem.
If the signal is good, then I would start leaning towards a PSOM problem.
Does the speedometer fluctuate as well? many times it can be a bad RABS module pulling down the VSS signal. I do recall reading a post from subford where the VSS output should be in the 3.5 -4.0 volt range when the speedometer indicates ~30 MPH. That was from memory, I suggest you search a few of his posts.
That would be the best place to start. If the signal is low remove the connector from the RABS, see if the signal level increases. If it does then you know it's not a VSS or PSOM caused problem.
If the signal is good, then I would start leaning towards a PSOM problem.
No issues at all with the speedo. Thats what made me think its not the RABS.
Thanks for the help. Ill try that. I send ya some reps.
I was having the same issue with my 94 150 a few months ago, kept shifting hard and throwing code 452 I tried everything mentioned so far. Ended up pulling a psom from boneyard and it fixed it cost me 45$
Slams in reverse then idle surges bad and then stalls out. Only does this when warm.(25 miles to work then backing into parking spot) When cold it does not stall in reverse.
Any test I can do to determine if its the PSOM, RABS module, or computer thats causing the issue. Id rather not guess and dump a ton of money into something I didn't need.
Have you checked for codes since this new issue started? The most likely cause is a gummed up or bad IAC. Pull it off and inspect/clean it. Have you pulled the PCM and opened it up to see if there are any signs of leaking capacitors or burn marks?
This may or may not be accompanied by irraddic idle and/or codes. If no codes are found pull the IAC (Idle Air Control) sensor and clean/replace as needed.
Another potential problem is that the transmission filter may have dropped into the pan. This is easy enough to fix. Remove pan, reinstall filter, fill with fluid.
Thought about the filter falling but wouldn't it do it all the time and not only when warm?
Pulled codes again and only got the 452.
Thanks for the link though. Think Im just going to take it to Ford.... I know they are going to rape me but I don't really have any other choice.. I actually can say I have more money than time for once in my life....