Bad idle

[Nickey2729]

I have a 2006 Tahoe has a rough idle to it. The check engine light has been on since I bought it. Just today it has started to lug really bad when climbing a hill or when you give gas for acceleration. When this happens the check engine light will start flashing up to 37 times in a row. We have changed plugs , wires, and oil
Any ideas as to what else I may need to check ? With it missing it doesn't use gas badly , this is where my confusion lies.

Please help a gal !!! Thanks !

 

[lesterl]

You may have a lean misfire (the fuel pump may be on its way out), Altho I would post this in the proper part of the forum (this part is for the 1995-2000 square body style)

 

[jlawz]

look for a vacuum leak! give special attention to the manifold area along the driver side. my 01 was doing the same thing and it was just a simple vacuum leak. Good Luck!!!