Engine/Transmission (1998.5 - 2002) persistant drivability problem.....help

[Qualey]

We have been battling some severe surging/engine dying problems and are running out of ideas. The background is as follows;



With comp box on OR OFF (wire is tapped) the truck lightly bucks and surges under light load at app. <2000 rpm. Replaced TPS and ECM (TPS due to code, ECM due to suspected voltage issue)



Truck still shows same symptoms, but these are amplified when box is turned on



A compounding issue, and one that we felt was a separate matter caused solely by faulty ECM, is the trucks tendancy to increase the idle speed after ~30 minute runs at highway speeds. The longer I drive, the higher the rpms until finally at ~1400rpm the truck will drop to normal, show engine light and go to limp mode. Zero throttle response. Sometimes switching ignition on to off will cure it, usually not.



Sorry for the length, but this truck only has 136k and I do not want to replace it. However I rely on this company truck too much to keep getting stranded. We are going to try a replacement TPS now, and monitor progress. FWIW, the Edge comp has been reflashed. Second injection pump, third lift pump.



Vehicle is 2002 4x4 ho 6 speed with 275s.



Thank you all.



Matt

 

[SnoKing]

If you do not have the comp grounded to the drivers neg battery term, then do that. The air horn bolt is not a good enough ground for the comp and the instructions indicate. SNOKING