93 yota questions

just picked up a bagged yota, I have a couple questions. Question 1 the truck runs at normal operating temp but the heater doesn't get anywhere close to blowing hot air, could that be the heater core? and question 2. After the engine gets to operating temp it continually revs up to about 2500 rpms and drops down to about 700 rpms what could cause that? ANY HELP PLEASE!!!!!!!!!!!!!!!

it's low on coolant, my old yota did that, and I know of a couple others that have done it too

Edited: 2/16/2007 11:33:38 AM by HOLCOMBE347

check the coolant. a friend of mine, her car was having heating problems...the temp would be normal but it didnt blow warm air. turned out to be low on coolant and now its fine. its pretty rare that a heater core goes bad, not saying that it cant happen but i would try everything else first before you pull it out...cause a heater core is a pain in the ass to get out. as far as the rev problem, check all your vaccume lines. be sure they are snug and there isnt any cracks in them. also if the truck came with a/c but doesnt work or whatever, make sure the a/c switch is off. i noticed on my 88 that (my a/c is broken) if i pushed in the switch at idle the truck would rev up and down. like it was looking for a drag to comensate for from the compressor kickin on.