We have a 97 F250 with the 7.5L V8. The truck is pulling codes 173 - EGO Not switching, Rich Exhaust Bank 1 and 332 - EGR Valve Not opening.
The truck Idles very rough, and blows black smoke when reved from an idle. It runs smooth at higher rpms though, and seems to have its power. We do have alot of miles on the truck, but until this problem, she ran great. Any help would be much appreciated! I'm trying to get her running well for the winter. Thanks guys!
I think I would check the Fuel Pressure Regulator. Make sure that the vacuum pipe going to it is good and then pull the vacuum pipe off the FPR and look for signs of gas in it. If any found replace the FPR.
Engine off key on - Shoots up to about 55 psi, and slowly drops down 20 and below. Engine running 70 - 74 psi (bouncing around). Turn engine off drops right back down to next to nothing. Sound like I need a FPR? Also - On the vac lines there is a small cylinder with 2 vac lines on the top of it and a plug with 2 leads in on. Any idea what this is? Thanks for your help guys!
Put the new regulator on, and It runs so much better. Runs at 30 psi, and holds pressure after being shut down. I was amazed at how much better it ran with the new regulator. Still have the codes, so I'll be clearing them, and I'll be pulling it out tomorrow to run it and see what codes I get. Again though, If anyone has any idea what that vacuum valve is, let me know! I'm very interested to find out what it does. Thanks again!