Replaced plugs, wires, and air filter.
After a 10 mile test drive, the truck is idleing at 1k rpm. The truck is running great down the road and very responsive.
I put in Autolite XP irridium's, Bosch wires, and Spectre filter.
I know the plugs are supposed to be gapped at .040 but these plugs were at .055. i was told these plug's gap could not be changed.
Upon first start, it had a very slight hesitation and then fired right up and sounded strong.
I reset the Ave. mpg meter in the DIC and on my little test drive, it bounced from 6.2 to 9.1 mpg and everywhere inbetween but never got higher on my test drive. Before the tune up i was averaging 12 mpg city.
I sent the wife to work in it this morning and she said it's running ok but brought up the fact of the higher rpm's too without even knowing about it before hand.

ideas on the rpm's and mpg's?

Thanks,
Mike D.

 

Check around everywhere you worked to look for any unplugged wires or vacuum hoses. Also see if any hoses are cracked or brittle. They may look good and leak at the same time.

 

good thought. i'll look some more.
i cleaned the throttle body too and thought maybe i left something loose. i couldnt hear any leaks anywhere though.
thanks for the input! <!-- / message -->

 

Probably should've stuck w/ AC plugs that you can gap correctly for one thing.

 

Ac delco plugs would have been a better choice however they are not/ will not cause your idle problem. You need to provide some more info. What year truck and what size is the engine?