I've traced an annoying problem ive been having to the egr: My car is hard to start cold, stumbles for a while after first started, sometimes dies on deceleration, and surges at crusing speeds. My question is, how do i tell what i need to replace. Is it the egr valve or the egr soleniod?

Thanks

 

Is there an error code stored in the ECM? You might be able to eliminate the EGR valve itself as the problem by removing it and inspecting it for proper closure, cleanliness, and function. On my '95 it is bonedog easy to remove, but slipping it past the EGR plumbing to get it out of the engine compartment is a little tricky (but possible because I did it). Mine was dirty with quite a bit of build-up. With the valve in your hands you can depress the vacuum diaphram and observe how it returns to the closed position, if it feels tight or encumbered, etc. If it's got a lot of build-up on it you're probably better off just buying a new one ($43 or so from Jeff Kopp, $47 from Advance Auto Parts for Delco brand), because trying to use a solvent (I tried Throttle Body Cleaner) can tend to gum it up and make it not close completely or be slow to return to the closed position. I know because I tried cleaning mine this way. I ended up cleaning it up okay, but used a LOT of TB cleaner. I also sprayed TB Cleaner on the valve travel shaft while holding the vacuum diaphram fully depressed (to expose all of the travel shaft) and worked it back and forth many times while re-spraying, until the shaft stayed clean and had no more broken loose build-up visibly hanging on it. Once that was done and dry I repeated the procedure using a semi-dry (low petroleum lube content) silicone based spray lube on the shaft. I didn't stop the cleaning process until the valve would hold any TB cleaner I sprayed into the end of it and not let it seep past the valve and into the duct-channel in the valve base.

I don't know if this is the approved process for cleaning an EGR valve, but it's what I did and the car doesn't run any worse, maybe a little better, maybe...

 

whoops sorry forgot to say i throw a code 32, it comes and goes.

code 32: Exhaust Gas Recirculation Circuit

 

Get a vacuum pump and see if your EGR valve will hold vacuum. If it is like my 87 you need to apply about 14 inches of vacuum before it will hold then it bleeds of slowly. If you need a new valve by a GM one.

Does your year have the EGR temp switch? I screws into the passenger side exhaust manifold and the wire runs behind the distributor? If it does this could be your problem. When mine went bad it would give me a code each time I started the car when it was cold but not if it was hot.

As for the solenoid, you'll need to follow the procedures in the shop manual to test.