Hey Blacksnapon, Checked out relay wiring today found that I do have 4.96 volts on command wire from module and found hot looking relay power terminal, replaced relay, still no compressor operation. Further checking and found that power supply terminal on relay plug was not making contact to...

thanks for the troubleshoot info. I will check some more tomorrow. I checked relay wires and am not getting a ground signal from the module wire.

air suspensionThanks Blacksnapon, A friend and I scanned dtc and found c1830, cleared code and retested vehicle, same code returned. After commanding rear vent, vehicle dropped and then compressor would not operate. I jumped out relay behind headlight and no compressor operation. I replaced...

My 2000 expedition will trip ck susp light when idling sitting still for about 4-5 minutes, during this time compressor cycles on / off before tripping light. Most recent condition is that when riding down the highway the ck susp light will come on and the rear susp will drop slowly in about...

cold rough idleThanks for the reply I will check it. I do not get on site to often, not much time available. all you FTF guys are a great resource.

I had this problem and used a timing light while driving, it would go out just before stalling, it turned out to be ignition switch mounted near the bottom of steering column. You also say it happens in about the same distance of driving, is the engine warming up and choke is opening which is...

cold rough idleMy 2000 expedition is doing the same thing since cold weather started. Did you find the fix? Was it the IAC?

IAC & throttle body are clean & clear, Idle Air Control is new.

I have a 1989 F-250 5.8L, I have replaced or tested with "none good" all sensors and computer. Truck does not seem to have any vaccum leaks, no codes are present. If truck idles for more than 61 seconds (throttle untouched) a surging starts. Cat is unobstructed, timing is correct, base idle is...