ok cool. check engine light came back on after i ran it for a while. still getting codes 171 and 174. so guess the gaskets werent the problem. more work to come i guess lol.

 

If both banks are lean and the lower intake gaskets have been replaced and the code is still there, check for any vacuum leaks, throttle body gasket, iac gasket, intake snorkel, low fuel pressure, dirty MAF etc...usually the intake gaskets arent suspect unless only one bank is leaking.

 

ok will do that stuff thanks.

 

start the truck and spray carb clean on all the areas where you could have a vacuum leak

-lower intake
-upper intake
-iac
-throttle body
-all vacuum lines
-intake hose from air filter to throttle body
-maf sensor
-air filter gasket
-check fuel pressure
-new fuel filter?

 

fuel filter has been done pretty recently, just took things apart to inspect gaskets and all seemed to be in good shape. dont have carb clean so i might have to get some... if i took to a dealer they could put a vaccum gauge on it to check to see if im losing vaccum?

 

that wouldnt be a very accurate way to tell because if you have a vacuum leak, your gauge vacuum reading could still be correct.

if you took something apart you cannot reuse gaskets just an FYI

 

alright, just wondering how to get this problem solved.