Had similar problem with my Dad's '86 T-Bird, on his it was inability to idle (sometimes it would, sometimes not). It was the injectors, they are not "Monitored" by the Computer, The computer just "operates" them. However when they act up, they do make other things throw codes randomly.
The 1st thing we did was the coding w/ the Scanner--It take s a bit to catch onto--listening/ watching the flashing light/ beeps and counting---watching it go thru a sequence
I was pulling my hair out and made several trips to the salvage yard and obtained nearly every sensor (2-3 of each) off of T-Birds and Cougars
I thought surely they all cannot be bad, I got a bagful for like $10!
My intentions were to figure out which one was being evil----THEN BUY A NEW ONE!
My Dad and I wound up taking it to the feller that the stealerships take their problem cars to. He let me watch the process.
Everything was in perfect order, He put stuff on an oscilloscope, and explained what he was doing. The only thing he came up with that was not perfect was the TPS--I had replaced it with 2 from the salvage yard and wound up buying a new one from Advance Auto (This new one was supposedly bad)
This feller even confirmed "Base Idle" was dead on (another learning experience). Don't mess with the adjustment screws--I learned that throws the computer out of sync with the sensors---there is a specific procedure to get it right----at least I had got it right before this guy checked it out
Dad paid the feller $200 and off to the stealership for the "OEM TPS". It's cost was much more than Advance Auto
Guess What?
This did not work, in fact, I took it back and got another
Same deal. Will not idle!
I was on the Verge of Suicide.
My buddy had went back and got the whole throttle body off of a wreck that had low miles, for $20.
I laughed when he showed up and gave it to me.
He said this is the only thing we haven't tried, the price was right!
Every other knowledgeable person (I talked to many, many people) insisted it was a sensor problem and I had spent a MONTH changing everything in the world.
I even had a composition notebook started w/ what I had done, the various code changes I got, How it ran, how long before it would not idle
It was the Two INJECTORS the Whole time!
Need a Bagful of sensors?
I am not a Paid Mechanic (as you can see) I do know Jeep CJs very well (They don't have a computer)
I hope this could be your problem, maybe you can try some used ones prior to buying new ones, just to be sure.
You could just use the excuse I use to justify getting new parts, whether it's the problem or not---"It's gotten the car to $300,000 miles already, something new is just preventative maintenance. The car is paid for, this is way less than one payment on a new one!"
The Medic
Friday, December 30th, 2011 AT 5:52 AM