since geo prizms have corolla engines........

we've got a 95 geo prizm, the cooling fan runs constantly, even tho the engine is cool, after a couple of days, the idle was kinda funky, it would drop a couple hundred rpms, then go back up. we've changed the temp sensor an' the cooling fan switch, can anyone help?

the fan relay contacts may have electrically shorted [welded shut].

Using an ohm-meter, does the cooling fan switch [with the wires removed, and the engine cool, and key off] indicate an open or closed switch?

OR...If Pre-owned....

Someone may have bypassed the control circuits all together and wired the fans to the ignition [run] curcuit.

I can't remember if the control circuit swithes the positive or negative side in and out of the loop....I'll see if I can find the schematic

the idle was kinda funky, it would drop a couple hundred rpms, then go back up. we've changed the temp sensor an' the cooling fan switch, can anyone help?

if acting kinda funky, check oxygen sensor, some corollas been having that problem