Engine was pressure washed, now the idle is running at 2000 RPM and slowly rises. 1993 Ford F-150 5.0 EFI. So far, here is where we are at...
No vacuum leaks.
No disconnected wires.
All wire harnesses were sprayed with WD-40 to displace any water that may have gotten past a seal.
Recently replaced the following: Cap, rotor, plugs, wires, coil, tps, iac unit, egr valve and motor, cold air intake k&n, fuel filter, o2 sensor, and tranny serviced.--(Engine was running awesome after these replacements)
Now, immediately after the engine was pressure washed, the engine idle is high. While driving, the throttle is slightly more engaged than I would like, and the truck will not slow when you let off the gas. Oiled the throttle cable where it connects to the throttle body, no luck.
All fuses have checked fine. When I disconnect the IAC valve, I get an engine that idles where it's supposed to. I took the IAC apart, it's ohmn resistance is within specs. It's internals are clean and engage properly.
So, I'm thinking I have a sensor problem. Air Charge Sensor, MAP sensor, coolant temp sensor, barametric sensor, or ECM failure? Any help would be appreciated as this is probably going to start getting expensive.
The vehicle has had a day to dry out, lots of wd-40 to displace water. Please don't offer anything that I've already written about trying.
If the IAC were stuck open, when I disconnect the wiring, shouldn't there be no difference in idle? The IAC disconnected is closed, when powered is open. Makes me think a sensor before the IAC could be to blame.
No vacuum leaks.
No disconnected wires.
All wire harnesses were sprayed with WD-40 to displace any water that may have gotten past a seal.
Recently replaced the following: Cap, rotor, plugs, wires, coil, tps, iac unit, egr valve and motor, cold air intake k&n, fuel filter, o2 sensor, and tranny serviced.--(Engine was running awesome after these replacements)
Now, immediately after the engine was pressure washed, the engine idle is high. While driving, the throttle is slightly more engaged than I would like, and the truck will not slow when you let off the gas. Oiled the throttle cable where it connects to the throttle body, no luck.
All fuses have checked fine. When I disconnect the IAC valve, I get an engine that idles where it's supposed to. I took the IAC apart, it's ohmn resistance is within specs. It's internals are clean and engage properly.
So, I'm thinking I have a sensor problem. Air Charge Sensor, MAP sensor, coolant temp sensor, barametric sensor, or ECM failure? Any help would be appreciated as this is probably going to start getting expensive.
The vehicle has had a day to dry out, lots of wd-40 to displace water. Please don't offer anything that I've already written about trying.
If the IAC were stuck open, when I disconnect the wiring, shouldn't there be no difference in idle? The IAC disconnected is closed, when powered is open. Makes me think a sensor before the IAC could be to blame.