My 2008 Endeavor is the first new car I've owned in 10 years and things have changed. Anyway at 30K miles it was time to change the front brakes so while I was at AutoZone I picked up some new plugs too (Bosch +4s). What a mistake, I ultimately learned. Read on.

After changing the plugs (took me hours) and brakes (took 30 minutes) as soon as the car reached normal operating temperature the SES light came on and the TCL turned off. That lead me to read here and other places and learn I didn't need to change the plugs at all. Anyway I went out and bought a scanner and found the codes were 0717 and 0174, engine running lean on both banks, and read here and elsewhere that suggests a vacuum leak, dirty or defective mass airflow sensor or - I read from one mechanic - the plugs are wrong. So next thing I did was replace the +4s with Mitsu specified NGK iridium plugs (per my owners manual), couldn't find the Densos, and took extra care to clean all the surfaces on the intake manifold. I also cleaned the mass airflow sensor with the CRC cleaner made for that purpose. Put it all back together and . . . same problem.

So far every lesson has been expensive - I've been working on my own cars for nearly 30 years but have to admit I've haven't kept up with all the changes (beginning with, iridium plugs last more than 30K miles! Boy do I feel stupid!). If I can't get answers here I'll probably end up taking it to the dealer, but I thought I'd give this a shot. BTW I've checked all the vacuum lines, etc., and everything is connected and in good condition. Thanks for any and all help!

 

I also poured a bottle of Chevron fuel injector cleaner into my 3/4 full gas tank while I was at it. Just in case that's a possible culprit . . .