Just did a paper-clip check on a check engine light and I am getting 122 (122 (O,M) TP low (possibly grounded or open circuit) ) (http://www.thorssell.net/hbook/3digit.html). I just got done replacing the TPS this weekend after the old one was bad. I checked the connection for it and everything was connected well. Can anyone further explain the code and tell me if I messed something up? Any help is appreciated!

 

Did you disconnect the battery when you were changing the TPS to clear the codes?

 

Yep, negative was disconnected.

 

For the record, I was not getting a check engine light before I changed the TPS. Before I changed it (and the MAP sensor) I was idling bad, and often stalled when shifting out of park, which has been mostly taken care of by these changes (the idle drops down from about 11-1200 to about 650-750 when shifting, but doesn't come close to stalling, so it's really just idling a bit high).

 

You have a vacuum leak. I don't suppose you cleaned the throttle body with spray cleaner while it was still on the engine?

 

I gave it a solid wipe-down of the build up inside but I didn't use any cleaner, and it was fully off as that's the only way to get to the TPS screws on these model. Also the gasket looked to be in really good shape so I didn't replace it.

 

Spray cleaner in the TB while still on the engine will kill the upper intake gasket causing a high idle. You still have a vacuum leak and the PCM can't make the high idle mate with the low reading on the TPS. Check all vacuum hoses and the PCV in particular. If you've replaced the PCV with a non-Motorcraft part, that could also be the problem but there's air getting into the engine that's not going thru the throttle body.

 

Any tips on getting to the PCV valve? I've checked every hose I could get to but couldn't find any leaks. Moving on to the PCV next, but it's a real pain in the *** trying to get to it on these years 302's.