1990 Celica - New radiator reduces gas mileage?

[tvmaster]

Hi there. Due to overheating caused by a blocked radiator, I had a new rad installed in a 1990 Celica ST with manual trans and a 1.6 engine - all stock.

Funny thing - I was getting 30-32 MPG average before the new radiator was installed.

But after the new rad went in, the average has dropped to around 25 MPG.

Fairly drastic change.

Any thoughts as to what may have caused the drop-off? Does an engine that's running unusually hot get better mileage?

thanks

[hatchy_gt-s]

did you replace the thermo?

[tvmaster]

Originally Posted by hatchy_gt-s

did you replace the thermo?

Actually, I did. What could be left?

[jlspec]

Make sure the themostat is a toyota OEM, aftermarket sucks. Did you bleed the system of all the bubbles? In any case, when a car overheats it could cause more damage then it might of looked in the first place. You might want to do some tests and do a full tune up. That's always the first thing to do when trying to get more MPG or fix a MPG issue. Oh, don't forget to change your fuel filter, and gap the plugs. Toyota/aftermarket always claims that the plugs are pre gap but its a load of crap. Again use OEM parts to insure the best repair.

[Pineapple]

You sure everything is plug back in after the swap? Like O2 sensor?