Hello all. I have recently purchased a 91 F350 dualy. It has a 460 EFI. I am having some problems and need some help please. For starters, the truck sat with little use for the last year or so. It fires right up, but stumbles off ideal? The check engine light came on and the codes dtc: 32, dtc:41, dtc:63. I replaced the o2 sensor, no change. I had the cat tested, it was giving to much back preasure, so removed it. I replace the throttle position sensor, still no change. Removed the idle control and cleaned it, reinstalled still no change. The check engine light comes on every now and then, it's not a constinuos on. Any help would b greatly appreciated. Thank u in advance!

 

32 is EVP sensor issues (EGR Valve Position). EGR/EVP Codes 31/32/33/34/35 Troubleshooting

41 is HEGO reading lean/always lean, which could be caused by a vacuum leak.

63 is TPS circuit below minimum .6 volts. Part 1 -How to Test the TPS (Ford 5.0L, 5.8L).

 

Thank you. I will look into those

 

I think the main thing to keep in mind is that the O2 code could be caused by something else. Vacuum leak, EGR valve stuck open, etc.

 

Thsnk u again bob. I have sprayed carb cleaner around the engine looking for leaks, didn't find any. I need to check my plugs and see if they r faulted. I pulled the egr and Idle motor apart and cleaned them. Today the code was runnin rich. It had been saying running lean.