Do you guys consider a Yukon 4x4 in the same line as the Blazer ?
Hope so.

Anyway,, it's a 350 Vortec 220,000 miles that runs great.

Hot start after sitting 15~ minutes requires a bit of grinding on the starter, then it idles roughly for a bit, then runs fine.

Oil pressure is a bit on the low side, like 20~psi Hot

I'm thinking the fuel pressure interrupt via the oil pressure switch may hold the fuel pump off till oil pressure builds up.

Any thoughts ?

Thanks
Doctorvette

 

Technically, it's not a K5. Solid axle = K5 which died after '91. We'll try not to hold it against you though.

Minimum oil pressure is ~8psi at idle so 20psi when hot is more than adequate.

When was the last time a tune up was performed?

Have you tested the coil? Maybe it isn't putting out the proper spark when hot?

Also, have you checked over all of the vacuum lines, throttle body base gasket, etc for leaks?

 

I'll give those ideas a shot.

I don't believe in the tooth fairy anymore or in New Plug Wires;

clarification, per GM's service manual, plug wire resistance should be between
12,000-15,000 ohms per ft
Haynes says a max of 30,000 ohms

I grab used wires at the junk yard or wherever, clean em with brakekleen, lacquer thinner and coat down with silicone grease, of course check the metal ends for a good snap-down upon installing..

GM's coils tend to leak to the bracket, which may be worse when hot. I'll grab my toy stethoscope and give it a listen..

Thanks for the thoughts

Doctorvette