I figured two forum posts are better than one, and I know you Chevy guys can help!

I bought a 1993 GMC K2500 with the 5.7 and 5 speed manual. I bought it from a friend who got it brand new in 1993. In 2002 he bought a new GMC and parked this one with plans of using it around the farm. After 3 years of me bothering him about the truck and him only driving it a handful of times in a year, he got tired of it sitting there and sold it to me for $500. Heck of a deal for a truck with no rust, great interior and only 149,500 miles.

Brought the truck home and noticed hesitation due to old gas. Alsoafter it is driven around for a bit, if you shut it off it will not start for a little while. The engine will crank and crank, but not turn over. I've found that if I spray some water around the area of the EGR Vaccum Solenoid (left side of the air cleaner assembly), that it will start upright away.
Here is a list of things I havedone so far:
Recharged A/C
New Bosch Platinum Plugs and Wires
Oil Changed with Mobil 1High Mileage Synthetic
New Air Filter
New PCV Valve
Power Steering Pump
Stopped Small Radiator Leak
New Fuel Filter
Marvel Mystery Oil Treatment
Seafoam Treatment in the Engine

This truck is in great shape, and the cruise control even still works. The first problem I have is that sometimes I'll crank it up and drive it and it runs like brand new! Other times Ill crank it up and it idles at only 750-800 rpm, it hesitates in first and second, the oil pressure fluctuates on the high side more than normal, and the temperature gauge rises on occasion. It doesn't feel like it should at all. Then it wont start if shut off after its warmed up. The second issue is the factory radio. The radio power on and lights up, but it stays frozen on one station with no sound and none of the buttons function. I know its not a big deal, but I have to have my music on and I do not want to put in an aftermarket radio.

I know if anyone can help me, you guys can!! Thanks a million!

 

you need to find out what is "missing' when it fails to start...see if you have spark...and check the fuel pressure

 

Try spraying some throttle body (not carb) cleaner in the throttle body. It is probably pretty junked up. You prob need to do a radiator flush too. Make sure there are no vacuum leaks particularly around the throttle body. Platinum plugs aren't the greatest thing to use on these trucks, standard duty ACDelcos or NGKs will work better. Also it sounds like your EGR needs replaced (it sounds like it is getting stuck). Replacing the vacuum line to the EGR won't hurt either. The stereo will prob need replaced, mine quit on my 91' and I couldn't get it working again for the life of me. It did the same thing where it froze up. The stereo installation kit for those trucks is kind of pricey too.

 

the aftermarket install kit on those is very reasonable, about 15 bucks for the new tray wiring harness and crimps. not to bad if you ask me.

 

Did they still have the radio by the instrument cluster on those? My 91' had that 5" X 5" radio and you had to buy a kit to move the new head unit to the center of the dash and it was about 100 bucks for the wiring harness, the dash trim piece and the tray to put in where the old radio was.

 

Yeah, the radio is still the 5 x 5 in the instrument panel.

 

Get yourself a standard duty head unit for around 100 bucks. Install kit prob just under 100 bucks for everything. Get a head unit with a remote, you won't want to reach down all the time, trust me. Then you can get it installed for under $50, you'll be uner 250 bucks.