Do you mean it runs fine for the first 4-5 minutes or so after a cold start?
If so, then the trouble is after it goes into closed loop and is probably sensor related.
Is the CEL lit? I'd try pulling the codes first and see if any shows up.
http://www.auto-diagnostic-codes.com/Petrol-Engine/North-American/Ford-US-Powertrains.html
Might be a faulty TPS or even an O2 sensor. Don't pay for new parts yet though, before you read the code(s).
If so, then the trouble is after it goes into closed loop and is probably sensor related.
Is the CEL lit? I'd try pulling the codes first and see if any shows up.
http://www.auto-diagnostic-codes.com/Petrol-Engine/North-American/Ford-US-Powertrains.html
Might be a faulty TPS or even an O2 sensor. Don't pay for new parts yet though, before you read the code(s).
I agree. Even if your CEL isn't lit you might still have codes stored. Definitely check them before you spend any time or money doing anything else.
John, the timing isn't adjustable on the 92.
You're right, there isn't a code 90, or at least one that I could find. I'd have another store read it again, to confirm that's really a bad code. Shucks may have had a bad code reader.
Since your trouble starts when it goes into closed loop, it's almost certain a faulty sensor is the cause.
Code 91 is an O2 sensor 'always lean' code. That's the closest to a code 90 I could find.
You're right, there isn't a code 90, or at least one that I could find. I'd have another store read it again, to confirm that's really a bad code. Shucks may have had a bad code reader.
Since your trouble starts when it goes into closed loop, it's almost certain a faulty sensor is the cause.
Code 91 is an O2 sensor 'always lean' code. That's the closest to a code 90 I could find.
Ford probably put timing marks on the crank for diagnostic purposes; you can still check the timing even though you can't adjust it. The ECM uses inputs from the CPS, TPS, MAF and MAP to set the best timing for any given engine load.
Any luck on the code? I still can't find a definition for a code 90. Those are generic codes though, and I can't figure out why one number (90) would be skipped.....?
It must mean something, maybe a factory testing code....?
Since it's in the number range to be O2 sensor related, you might try checking the sensor wiring to make sure it's not burned from the exhaust manifold, loose or broken.....
If you're good with a multimeter, the O2's not hard to test, just 3 wires to check on a 92.