EGR Valve

Tahoe service engine soon lamp comes on after 10 minutes from cold start. ECG code is EGR trouble. 200K mile on tahoe changed EGR valve and solinoid.
Checked all vacuum lines. Lamp goes out after shut down and stays out from then on when warm.

When you replaced your EGR, did you disconnect your battery for several minutes. Sometimes you need to do this or the computer will still think it has a problem. On a side note, usually when an EGR goes it could be because of carbon fouling or the Temperature sensor may be bad. But disconnect your battery, I usually waite a 1/2 hr or so just to be sure. If the SES light comes back on have it check and if you have a P0400 or P040X then you know you for sure you have an EGR problem.
P0400 Exhaust Gas Recirculation Flow Malfunction
P0401 Exhaust Gas Recirculation Flow Insufficient Detected
P0402 Exhaust Gas Recirculation Flow Excessive Detected
P0403 Exhaust Gas Recirculation Circuit Malfunction
P0404 Exhaust Gas Recirculation Circuit Range/Performance
P0405 Exhaust Gas Recirculation Sensor A Circuit Low
P0406 Exhaust Gas Recirculation Sensor A Circuit High
P0407 Exhaust Gas Recirculation Sensor B Circuit Low
P0408 Exhaust Gas Recirculation Sensor B Circuit High

Thanks for the reply!
Yes I have reset the ECM. The only code in the ECM is 32 after 5 rounds of code 12. I am not familar with your P0400 or p040x code iformation, could that be using a code reader? I am shorting pins AtoB and reading the SES light.
This is the code information I have found so far.
32 EGR open command did not change the fuel mixture when the command was given during off idle operation. EGR opening should cause the mixture to be slightly richer because of the low oxygen content of the exhaust gas. EGR position signal is also monitored to verify EGR movement.
Do you know how in the last part of that the ECM gets a EGR position signal? There are no electrical connection on the EGR.
Where should I go next? I own another 95 Tahoe 2wheel drive and I am thinking of swapping the EGR componets now.
Thanks for your help
David

I have a 1996 chevy tahoe. I did the tune up by changing the rotor cap, distributor cap, plugs and wires.
I got 2 problems. First when I put the key in the ignition and crank it to start it I have to hold the key in start for about a second and a half, im wondering if that is normal for a tahoe or perhaps thers another issue with it.
Secondly the check engine light came on and after checking it with the ODB checker, it says that its is an egr problem. THat would explain why when idling the car sounds like its choking and not idling smooth, feels congested. I have been told that instead of spending $300 ++ on a new egr valve I could simply take out the one I have and try cleaning it. Will this solve my problem for the time being, seeing as to how in ontario we have emission test, and this wont allow it to pass. If I should try to clean out what do I use to clean it?