| 89RR Still no luck Posted by Greg on December 19, 2001 at 22:55:38: This is a continuation of the below posts "89RR Won't run, need some help". Thanks to all that have helped so far. The truck will barely run when cold (and surges dramatically) and will not run when hot. I've changed so many parts I don't know where to start. My plugs say that the engine is running very rich (black sooty plugs) I ran a fuel pressure check that failed and changed the pump, no luck, so I tested the fuel pressure regulator and that failed, so I changed it. Noluck. Even the new fuel pressure regulator fails when you pinch off the return line I get 70PSI. Finally I hooked up a vacuum gauge and found that the vacuum is so low, it won't work the fuel pressure regulator. Problem is I cannot find any vacuum leaks. I tested by pulling the wire to the stepper motor ICV, then shot carb cleaner around the vacuum hoses and listened for an RPM increase, no luck. Visual inspection of all hoses finds nothing. I've changed the following: cap, rotor, plugs, wires, fuel filter I guess I'm down to the Air Flow Meter or the ECU? Does anyone know how to test these? Or anyone have any other ideas? Thanks very much. Greg
|
