Good info., Kilna. I'm only on my first replacement and will probably throw one more valve at it before looking elsewhere. I have never cleaned my tube. I got the trombone cleaning brush but will see if I clean it this time around depending on the deposits on the valve. I'm reluctant to pop off the throttle body as I'm afraid I will introduce a new air leak. Is there a throttle body seal I should have on hand just in case?

WormGod, here's what I see on Rock Auto now; are you referring to the Delphi as the "GM"?

AIRTEX / WELLS 2M1 AdvanTech $80.79

STANDARD MOTOR PRODUCTS EGV589T T-Series $92.79

AIRTEX / WELLS 4F1139 Includes Gasket $97.89

STANDARD MOTOR PRODUCTS EGV589 $103.79

DELPHI EG10175 $112.79