1988 Chevrolet Silverado K1500 4X4 problems...?

[abpumprepair]

I just bought this truck. It has 150,000 actual miles. It has been in storage for the last 5 years. When I first bought it, it ran great. Now after 900 miles, it shakes at idle, misses at idle and after idling for about 4 minutes, it smokes like crazy. Blue. Give it a little gas and it clears right up, both the idleing and the smoke. I am getting 11 mpg highway as it is. 350 TBI motor. I have changed the plugs, wires, cap and rotor but nothing different... Any suggestions would be greatly appreciated.
I did just change the fuel filter but no difference. As for the valve seals..I should correct myself.. after a few minutes it smokes like crazy but if I let it idle, the smoke all disappears after about 5-6 minutes.. It does have a nasty smell coming from the exhaust, kinda gives you a head-ache if you smell it too long.
Also I should ad that once you step on the gas, all smooths out just perfectly.. I took it to the shop to get a engine code read and it say's that nothing is wrong.. also, the catalitic converter has been removed because I thought it may have been clogged.
went out this morning, started in and within 15 minutes the temp guage was up to 260 degrees at idleing, once I gave it some gas, it went right down to 195 .. head gasket??

 

[81Mustang]

The whole fuel system will be gummed up with gas varnish (the residue from the rotten gas) It normally takes a couple days of running it for all this to loosen up and start clogging everything up. Recommend you start cleaning/replacing the fuel system from end to end. Only other thing I could think of that might at least be a contributing factor is the valve seals dried out from sitting so long and are now leaking oil through, but then it should still idle okay so think most of your problem is fuel related. Also be a good idea to change at least the tranny fluid, you never know if it would get some moisture in there or something from sitting so long. Sitting for that long causes lots of little problems so don't be surprised if things like wheel bearings an such start to go also. If it was me I think I would change all the fluids in diffs, transfer case, repack the wheel bearings.......then you can eliminate annoying break downs. Good luck!

It could also have some sticky valves which would explain the miss at an idle, once it warms up the valves unstick.......If that is the case it should improve with time and you can try so engine treatments that are recommended for sticky valves and see if it helps, I trust you already changed the oil in the engine.

 

[patricia w]

If its blue smoke it's burning oil. If it's black smoke it's gas. Valve guides, valve seals, worn piston rings or cracked rings is probably your problem. How to check to see is those parts are worn out is a compression tester through the spark plug hole in all 8 cylinders. All 8 should be close to the same reading. That will give you an idea of the shape your cylinders are in.

 

[f100_supersabre]

After setting that long I'm surprised it started!

Have the TBI checked as it sounds like it is too rich at idle.
NOTE: Fuel has changed somewhat in composition over the last 5 years!