i got a code 31 EVP or PFE circuit below min voltage. car never used to do this till after i pulled the heads again. we don't have a PFE on our cars do we? can this be from to little backpressure in the exhaust?
44 and 94 are secondary air left and right inoperative. took off smog system. got this after h/c/i but after toying with some things i never got it again. now it's back.not sure which ones are throwing check engine light but i'm guessing mainly the EVP.
should i just replace the EVP and go from there? ford sensor or aftermarket?
any suggestions on ways to eliminate the 44,94 besides programming it out of the computer?
44 and 94 are secondary air left and right inoperative. took off smog system. got this after h/c/i but after toying with some things i never got it again. now it's back.not sure which ones are throwing check engine light but i'm guessing mainly the EVP.
should i just replace the EVP and go from there? ford sensor or aftermarket?
any suggestions on ways to eliminate the 44,94 besides programming it out of the computer?