I have a 89 s-10 blazer with a 4.3liter engine, and its egr system is not working properly.

When the egr valve vaccume line is dissconnected the vechile runs fine, but overheats quickly. When it is connected (the way it is suppose to be)it injects way too much gas and it floods it self out.

The egr valve does work it is new and so is the egr solinoid.

Any one have any ideas?

have you tested each component?

test the electrical to the solenoid and look for the triggering, then test the vacuum signal at the output to make sure it is turning on then off, then test proper valve movement and use a vacuum pump to test for leak down. lastly, clean the pintle seat.

EGR does not effect fuel flow and should not overheat a vehicle if unconnected for short periods.

Have your timing set.

well both the valve and the solinoid are new

but when i had a shop fix some other things for me they told me they dissconnected the valve vaccume line because the egr valve was opening at idel, which i guess it is not suppose to

anyone know anything about that

When you disconnected the vacuum line to the EGR, did you plug it?

When it is disconnected, you say it overheats. What is your description of overheating?

You said it is injecting way too much gas. How do you know this?

I am just trying to get a little more insight here.

yes i plugged the vaccume line when dissconnecting it

when it over heats, the engine gets too warm, thermostat gets to the rede line and i have even had the check engine lite come on because it got too hot

i started once with other people looking at it under the hood and they said it was dumping gas in

hopefully that helps

Check for a bad rad cap?

Is the fluid up to the top in the rad when you open the rad cap when completely cold? Replace the rad cap anyways to be safe.

Have you checked the thermostat?

Also check your timing with the brown and beige timing wire unplugged from the PCM under the carpet under the glove compartment.

the radiator cap is new and yes after every time it overheated i refilled te radiator and resiviour, the thermostat i dont know about but seems to function properly, it does open

i did have the timing set by a technician at a shop,

it was that technician that found:
EGR Valve was opening at idel, dissconnected vaccume hose

so i am still trying to figure out why it does not function properly with the egr connected

still check the timing and also check for a plugged rad.