EEC or EGR Problem?

It's port injection, right?

- PFE sensor fail/clog or clogged EGR tube?

If the idle 'hunts' or is always high, then look for a vacuum leak or a bad ISC valve.

Also if the throttle position sensor is bad, that will cause the problem. Esp on MAP(no MAF) engines.

Note: Believe replacing TPS on that model requires adjustment to .95 volts read with DVM, with throttle stop screw set for ~ 750 rpm idle, engine warm, (functional) isc disconnected and NO VACUUM LEAKS!

Which 13 is it? And like BM says check the TPS for the bucking/hesitation and pull the vac off the EGR too and try it. You can use a volt meter at the tps to test it, it should run at around a 1/2 volt at idle to about 4 1/2 to 5 at wide open. VERY slowly open the throttle and watch for a smooth transiston (of voltage) from closed to wide open. Do this several times. They seem to like to fail when the throttle is in the off idle/cruise area. If I remember correctly the Ferd scool teachers said to always fix lower number codes first starting with KOEO, then KOER, them memory. I would clear the codes right now, then start with KOEO and go from there. Oh, and since you can't see data on that year buy a book with emisions flow charts. Ford ECM's can diagnose themselves in a since if you follow the flow exactly. Of course its gonna suck a little when thy tell you to "install breakout box":( but you can get around that too. Oh, and don't ignore the "visual inspection" part. Good luck.

Oh, and another thing, clean the throttle bore and IAC first too. That alone might fix your 13 code.

Thanx "BackYard Mechanic" and "ShoeSalesman" for your help. First to answer your questions about how the code was obtained. At KOEO = 11 At KOER = 13, 32 Checked TPS voltage. Was at 1.2 volts. Was unable to adjust the TPS on engine so I removed the trotle assembly from the engine. Discovered EGR port and PCV port on the trotle assy plugged up. Cleaned out the plugged ports. Replaced PVC valve. Adjusted TPS to 0.73 volts ( 1/2 way betwee BM & SS advice). Truck now runs like a charm but. I still get code 13 & 32 at KOER. KOEO =

Does it seem to idle too high? That will cause the 13. Fix that first then run the tests again. It could be that the IAC is bad or dirty or idle is set too high. It would probably be a good idea to get a book on it and set the minimum air if the cleaning doesn't get it. The 13 code means the IAC can't control/lower the idle correctly.