Hello, normally I would not offer an unsolicited review of a product, however in this case I feel I should. We purchased our '94 Blazer with enthusiasm, only to find dismay with the EGR valve. The more research I do on this, the more I am disappointed.
After driving our new purchase for 6 months, we experienced much as the same problems that I have read about on this site: braking distance increased, stalling, lack of power etc. As recommended we replaced the EGR valve. Great drive for about three weeks. Tired of spending money without adequate results, we went to a GM dealer. We bathed the EGR valve for the recommended 4 hours... great drive for 2 days, returned the truck to bath it overnight... great drive for one week... now it is recommended we have a $1600 valve job done. After spending $600 dollars, now another 1600. Well from the research, it is clear this is a design fault. By some miracle when the truck was running well, we had the emissions test done (by law), it passed and we have two years before it is done again.
Now we are looking at a backing plate to cut off the emissions return capabilities. I'm told this won't hurt the vehicle, the only drawback is that it will leave the "must service engine soon" on... better than the $1600. For those who think that you can just clean it every so often, I spoke with a reliable friend/mechanic who has seen a vehicle 7 times for the carbon build up.
Tomco has also designed a replacement EGR gasket that contains a fine mesh, heat resistant screen that prevents the carbon from reaching the EGR valve pintle and its seat. Check out www.tomco-inc.com. I am not a sales or rep for this company, but I have contacted them for this gasket (only this morning without response yet). For those frustrated with the EGR valve... don't think it will solve itself after one trip to the shop. Good luck.
I love the truck when it runs well, and I don't mind spending money for maintenance - as long as the money fixes the problem. Be careful if your wife takes the truck or if you drive with your kids in the truck when it is showing the above mentioned signs. I am a big guy, and I have difficulties stopping quickly if this arises. Hope this helps...