2000 Isuzu Cleaned EGR valve and is stalling HELP?

just cleaned the EGR valve on my 2000 Isuzu rodeo and now I am having idling and stalling issues, the descriptions of the "pintle" were confusing, is there any way to resolve this issue? We followed the instructions to the letter, and now the car will stall out when in park, and when placed in drive , it seems as if the engine is about to stall. scared to drive it, the shop I talked to is saying that it is gonna cost about 200 bucks just to see what is wrong with it. help!