95 blazer 4.3 vortec 4x4
Took it in to Chevy dealer and hooked it up to diagnostic. Bad news, they couldnt tell me what was wrong with it, good news, they only charged me half price!! (GEE THANKS)

When the weather was colder, It would blow white smoke at start up, run rough (like I had a fouled out plug) for a minute or two, then when smoke cleared, engine ran fine. Drained motor and radiator, ran head gasket sealer through, drained and filled. Problem went away.

2 months later, no smoke, but truck is doing it again, only now it can take up to 30 mins at driving speeds to clear up. I just started replacing items when cash available. Have replaced: plugs, wires, button and cap, fuel filter. ran ok for a few weeks, and now its happening again. Today I replaced plugs (again), EGR valve, PCV valve and still taking about the same amount of time to start running smooth. Took it to another dealer to have hooked up to comp, foreman told me to save my money and cut my losses (save what money? The company I worked for just closed the doors!). So the problem is still there, and to top it off, after my test drive, noticed that the plastic end on radiator is cracked and spewing. Anyone got any tips on the motor so that I can justify repairing the radiator? Spider Fuel Injector?

 

How did the plugs look when you replaced them? Was there one that was worse than the others?

I would run a compression test and a leak down test to assess the health of the motor. If you have a head gasket, valve, or ring failure, these two tests will let you know.

 

disconnected my battery in attempt to reset computer. It running fine now, so I'm hoping that it just needed a little inspiration to recognize that the EGR had been replaced. Radiator repaired, but now i am hearing a gurgling noise behind center/slightly right side of my firewall (from inside the cab). Heater core?

 

The gurgling is due to air in your cooling system. Get it bled out properly and it will go away.

 

If it doesnt have too many miles on it or if your willing to play a little risk might try an injector cleaning. Go to a good lube shop they'll run it for you bottle fed through the vaccum line. I had this problem a while back ended up just bein clogged injectors. Look out for a lot of carbon blow through afterwards though. This could possibly harm your engine (so ive heard) never had any problems myself 225000 miles on my 95 and I keep premium in her or she spark knocks haha. Just a cheap idea that might help good luck!