have a 93 s10 blazer with 4.3 vortec in it. had cpl codes that came up for iac and egr took both off and cleand good with carb cleaner. put back in codes are gone. if it sits in park it idles good can give it gas and seems ok like has power put it in gear and drive and its a different story you can tromp gas pedal to floor and you have no power or accelleration its like the thing bogs down on you? what can be causing this? what can i do to check or troubleshoot my problem?

 

Fuel pressure? Specifically leak down rate?

 

whats leak down rate? went and got a fuel filter and fuel pressure regulator guess i will start there

 

Leak down rate is how fast (if at all) the fuel pressure drops after the pump shuts off. You basically leave the fuel pressure gauge connected and shut off the key then watch the gauge. If it drops to zero, you have a leak somewhere in the system.

You can also pull off the upper plenum, pressurize the system, and inspect for leaks. It will be quite evident if there are leaks.

Diagnose first and the replace the parts that are found to be defective.

 

i had a similar issue< check the coil and distributor. i replaced the coil and spark plugs and wires and its better than ever in my 4.3. but yah like said earlier it could be a fuel problem too

 

Check both fuel and igniton coil, and ign. wires, plugs, distr.-etc; Just to be on the safe side. weak/bad coils do exactly what you're describing, but so do fuel leaks, ( and bad fuel filters, and clogged lines too), like the gentleman said. Do diagnostics on as much as you can, so you'll have a good idea what to go thru the next time something craps out...

You never can be REALLY sure, until you have check BOTH the electrical (igniton part primarily) sytem, and fuel (supply) system-related parts.

Look at the bright side, by checking both systems NOW, (if you have the time to do so), you'll save ALOT of time and guess-work later. Although, you never know from one day to the next if a part, and/or system will shut down on you. Nothing like the world of electronics and mechanics eh? "Bring back the Horse" as they say eh?

Well, at least vehicles don't "talk back to you" like women do, (usually--LMAO), so there is more peace of mind that-a-way, right?

 

Well i had leaks in plastic fuel lines going to spider injector. Whomever put the fuel filter on last put a hole in top of it when mounting to frame rail so i replaced that. I replaced the spider injector as well. I also replaced cap rotor and plugs. It runs great but im still getting some carbon chunks lodging in EGR valve again, i had to take it off again and clean it then put back on and runs good. What happens if you do away with egr and put a plate on where it bolted to? Will this mess with computer? Can this be done without messing anything else up? Comments suggestions welcome and thanks again.

 

Good job finding and fixing the problems.

For your EGR, go to your autoparts store and head to the HELP! section and grab the EGR gasket that has a screen in one of the holes. Bring it home, clean the EGR one last time and put it back on with that screened gasket. The screen keeps the chunks out of the EGR.