1993 6.2 Diesel ECM
 

What does this govern? My trucks glow plugs used to flicker when driving before I had them manually overrode from the ECM.

My truck is a 1993 K1500 J CODE Swapped intake(originally C code(egr)), 5 speed manual NV4500, 4X4

When I kill my glow plugs from the ECM my truck idles lower. I also noticed random jumps in power.. and sometimes I notice gutless lagging speed.

Thanks for input

So I figured I may have a faulty lift pump.... when I turn the key I can only hear it for a couple seconds then quiet.This might explain the jumps in power and low idle speeds... Any input from anyone? Or would my ECM control my lift pump?!(doubtful)

with a 93 the ECM usually only controls the auto trans.
if you havea standard then I have no good ides what the ECM does?

I suspect that you may have a faulty oil pressure switch if the LPdoes not operate when the engine is running.
If you have a prime cycle on the LP circuit then it may have been modded to run with the glow relay?

GM 6.5L V8 Turbo Diesel EngineStudent Handbook
344 pages of AWESOMENESS! lots of pics and illustrations too..
Although not intended to replace FSM, it is far more accurate and useful than any Haynes, Chilton, or thers worthless 6.5 publications.

Suggest you down load it...

Check the fuel heater. It can malfunction and cause the WTS and WIF lamps to flicker on its way out, eventually it could pop the ECM fuse disabling the glow plug system and lift pump circuit..

hmmm I just hooked up the fuel pump relay to my battery and can hear it clicking away. But i dont hear it clicking at start up.

See attached.. You could simply unplug it, replace the ECMB fuse and see if everything returns back to normal. If so, you know the fuel heater is defective and wont need to remove and disassemble the FFM to properly "test."
If you find the fuel heater defective,, plan to replace it. FWIW a new fuel heater alone cost nearly as much as a new completely preassembled "drop in" fuel filter manager..

The lift pump relay only works during cranking,the OPS powers the LP while the engine runs.

Well I pulled my fuel heater plug and it ws completely corroded and basically broke off at the prongs. I think that is the issue.... Should I replace with a 6.5 fuel filter system? Can I run the truck without one?
I really appreciate your guys help.

Go ahead and run without it-does very little really.

Just be sure to use adequate amount of fuel conditioner for antigell.

I unplugged the Heater. I ran it about 40 km up the highway to class. The glow plugs still come on when accelerating out of 1st gear. It idles rough sometimes. I noticed steady power when my ECM was engaged but once my Glows came on i flicked it off and it got gutless. :dang:

Could it be my OPS?!!

So on my way home I couldnt get over 40 kms. Ran a 12 gauge wire from fuel pump fuse to battery and the fuel pump ran then died.

Better check if for codes,suspect coolant sensor problem?
AC Delco ONLY for replacement sensors.

gellin' maybe...

The reason for the fuel heater being in the middle of the ffm is to help the fuel pass through the filter element micronscopic passages during COLD WEATHER OPERATIONS..

It was my OPS. been replaced and running good. Fuel heater was rewired without the junction clips now. Still getting glows going off when accelerating before i switch them off