Having an odd problem. Started with Code P0122, Truck was running high RPM'* at highway speed. Normally runs about 1600 at 60mph but was running 25-2600 instead. Replaced the TPS. All was normal for the first day, no new codes. Took it for a long drive down the freeway one day, had the Cruise control set at 75 when the whole electrical suddenly went out and came back. Was quick enough that it didn't kill the engine at speed but was one hell of a jolt. Took it of CC and no more problems the rest of the way. Go to my destination and sat in a parking lot with it idling and it did it again. This time it killed the engine. Started right back up though. I've checked the obvious. Battery cables e.c.t. What the heck could cause it to do this?

Bad ignition switch. Very common in GM RWD manufactured in mid 1990s.

The high RPM may be a separate issue.

Forgot to add some info... Like said before. Replaced the TPS. Ran fine for a day then started the high RPM'* again and P0122 came back. Cleared it out to see if it would come back again. At this point as soon as i cleared it came right back before i even had a chance to unplug the scanner. I tried 3 or 4 times and at most it would stay off for a minute or so. As far as the electrical. Im also losing power to the power sockets in the truck, Those are always on. I noticed that a few days prior. My stereo and radar detector would randomly reset itself.

How are your battery connections at both ends? Sounds like a good case of corrosion at the terminals.

Both are clean. Just replaced the battery about 2 months ago.

Can you duplicate the power loss if you giggle the key switch forwards and backwards?

I'll give that a try in a few.

I wiggled it around in every direction possible for a few minutes, Didn't phase it.

sounds like u r possably got a bad ground connection

grounds or i think they have the double battery cable with the washer that doesnt really make when you tighten it.