Gremlins?

[outlaw5.9]

My "93 won't start with out being jumped and having the block warmed by the block heater. When I turn the key and wait for the wait to start light to go off the is a electrical "groan like" noise. I assume the noise is from the glow plugs or grid heater. By the time the wait to start light goes off the dash lights are very dim and the starter just clicks. Even with the battery having been on the charger for two days. If not on the charger the battery drains. Nothing is left on in the truck, I have checked many times. The battery load tests strong. When the truck is running the amp meter will go back and forth from the normal charge reading to about half of normal. This is really a problem because I then have to drive like an egg is on the accelerator or it gets hot. Could this all be caused by a faulty PCM. Do I need new alternator with a PCM on it. I have nto been able to find one seperate.

Also since my mods I have not been able to get my idle RPM's below 950. Any suggestions.

[Richie O]

Sounds like you have more then 1 problem on your hands.

[peobryant]

Sounds like you have more then 1 problem on your hands.

I agree.

[Richie O]

Try charging the battery and leave it unhooked. You may have a bad short in the battery. If it is charged, left unhooked and it still goes dead then its the battery. The high idle may be due to the fuel screw being in pretty far. Have you backed out your low idle screw??

[KTA]

With everything off you can unhook the battery cable and place an ampmeter between the cable and the battery. The draw should be less than 1 amp and should be about .5 amp or less because the only thing it is powering is radio memory.

[outlaw5.9]

The truck starts instantly if it is plugged in. If the glows plugs have to cycle to start the engine won't crank over. The dash lights start out bright ,but by the time the wait to start light quits the dash lights are dimmly pulsing and there is no crankig power.

[dpuckett]

Test the battery again. I had a similar problem, and had one dead cell in the battery. Above 30deg, and she'd crank over. Below, and no-go; grid heaters were on too long, and it took too much from it. Load test showed it down to 10volts at 750amps; tested each cell, and all others floated the little balls. One cell was DEAD- nothing. New battery, and she cranks and fires, grids or not.

What amp rating are they plugging in when they load test it? SHould be at least 1000CA. My mom is having a similar issue with her pickup, and I just havent had time to troubleshoot it. I unhooked the grid heater relays, and she can at least crank it without leaving it on a charger.

On to your fluctuating volt gauge. It is the voltage regulator part of your PCM that is bad. You can bypass the PCM and install an external regulator. Had it done in a 93, and the CHeck Engine light stayed on, but removing the bulb fixed that. (there is very little that the CEL will alert you to, since the fuel system is mechanical and all).

Daniel

[Oddfire]

The truck starts instantly if it is plugged in. If the glows plugs have to cycle to start the engine won't crank over. The dash lights start out bright ,but by the time the wait to start light quits the dash lights are dimmly pulsing and there is no crankig power.

Glow plugs?