beachlover

So I put brand new NGK spark plugs in ,and a brand new battery. All the time thinking I'm doing a good thing. But as I have been driving, the gas mileage display has been showing me getting 7-8 MPG when it used to show 20 MPG. Any speculation as to what's going on? No codes are being thrown either.

Baetke

Did you remove the intake manifold/throttle body to replace the rear plugs?

salimshah

What display settings do you have .. average or instantaneous?

you have lost your average value and new values are being collected. It can be that you have idled more and your new average shows poor milage. You can reset the average while driving on a open road and see the first few numbers settle around 20+.

Salim

beachlover

That would be too much work pulling the intake, even throttle body, to replace rear spark plugs. I just worked smartly with different extension sizes, etc.

Toggled back and forth with computer and resetting.

I decided likely candidate is MAF. So will try cleaning that.