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Sorry for your problem. I am here to try and assist you. Is the check engine light coming on ?
Hello, thanks for responding quickly. No light.
I there any spot in the accelerator that is a differn't rpm in any position of the pedal?
I have not taken it out of the garage for a test drive. I am about an hour away from the vehicle. I'll check out the
pedal position and contact you at noon, E.S.T.
ok i'll check in later. Jim
Just took it for a test drive. The accelerator is very touchy at the outset. A slight tap and it goes from 800 RPM to 2000 very quickly. At about 30 MPH it seems to act more like a big diesel engine. Very good power. I did notice some large
puffs of black smoke when I accelerated.
well after setting for 2 years you may notice temporay problems you seem to have done what you should have after setting for a long time. it would seem that the reostat in the foot control has corrioded. brb
It that a replaceable part?
I was looking online to see I run school buses an they have them and they do go bad and are replascable. they don't usually act like your vehicle but I'm not usually talking about setting around. I would guess the whole general motorsline would use the same controller. The biggest problem I have had with PMD unit on the injection pump. I'm still checking for the reostat.
You mentioned the PMD unit on the injector pump. I have read in Hummer forums that the placement in these
vehicles overheats them. I only have 53000 miles on it but what are the symptoms of a bad PMD unit?
Ok I just checked with my local chevy dealer and its avabilable. call a trottle position sensor
I'm at at work brb
I'm back sorry have to ans phone too. PMD problem are hard starting, quitting and not starting. the biggest problem is the positining on the back side of the injection pump. hidden down in the valley where there is no ventilation. I ended up making a long extention cable and moving it to where you would get air flow acrost it. always carry a spair. If you look on the internet you will find special kits.
Part No. 5714531
Sensor, Engine SpeedSensor, Engine Speed 6.5,For 4L80 equpt Truck,both Turbo and N/A
I also found that it has an engine speed sensor also may be be your problem. Please accept if i have helped with your problem. Jim
I also found this picture for the trottle position sensor.
Part No. 5714530
Sensor,Throttle, PositionSensor, Throttle Position, 6.5 N/A and Turbo with 4L80 Transmission, Military Only. May not be yours but simalar. Jim
Sorry for not getting back to you. The key point that you overlooked was the black smoke on acceleration.
I took it in to a mechanic and he diagnosed it was injector pump. I found one locally and installed it.
I am sorry I can not give you a positive rating because you were pointing me in a wrong direction.