EGR valve

How do you know when the EGR valve is bad? What are the symptoms? The reason I ask is the car started running rough and idleing rough. I had it checked out and they said it was misfiring and the catylitic converter was cloged. Changed the spark plugs and replaced the converter. It runs better but has an irratic idle and boggs out at 4000 rpms and when driving has slow pick up and boggs down when I stop the car almost stalling the car. That is why I think it might be the egr valve.
Thanks for any help.

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1997 Pontiac Grand Prix V6 Two Wheel Drive Automatic 185000 miles

3100 Engine. The code reader always says "Insufficient airflow to egr valve." The egr valve was replaced 4 years ago and has 50000 miles on it - seems a little early for it to go bad. I have taken the egr valve out and cleaned it/blown it out. I have also sprayed Seafoam into the tube and manifold passages AND blown them out as well.

What else could cause this message?

If you look at the hole in the middle of the egr real close you can see if it is working by pushing down on the valve its spring loaded just push it and see if it returns to seal. But the passege sounds like your problem to clean it you have to take off your throttle body and egr its hard to do yous hangers to clean it it will be all carboned up spraying wont do it you have to scrap it all out

1999 PONTIAC GRAND PRIX 3.1L 153,000miles

I Need to replace the EGR valve b/c the code reads it for my smog.

Is this something I can replace myself if I order the parts or must I go to a professional?

Parts: Gasket & EGR valve right?

This is definelty something you could do yourself with the right tools and just a lil time. I'm not familiar with the 99 grand prix so I can't walk you through it but I would check with your local auto parts store and ask what all you will need to change the EGR valve.

Got a code to replace egr valve and did. It made it better but did not fix the problem, loss of power, dogs up hills and wont increase speed if givin to much gas.
Could it be the covertor? Or what?

1999 Pontiac Grand Prix, 3.1L V6 158,000 mi. Check engine light is on. Fault indicated EGR insufficient. Should I replace the EGR Valve?

Car will not start, had diag. And it read it was that.

Just replaced an egr valve of a 1995 pontiac, since the engine light was on and this was shown to be the problem. The car is running better, however, light is still on occassionally. Why?

Sounds like the EGR tube may be getting clogged as well. Are you getting the EGR flow insufficient code?

If so, that EGR tube is your likely culprit. It's easily cleaned with some carburetor cleaner and a stiff-bristled pipe cleaner.

Ok I turn on my car sometimes and my car does not idle right the idle jumps around and then when I hit the gas then idle levels off and evrything is off. Sometimes the car is hard to start and ideling is rough.
My check engine light came on and code said egr valve stuck open.

You think I should change it cause I tried to clean it and I changed the gasket and still samne thing