I'm having some problems with the new(used) motor just put in. At idle it fluctuates between 700-850 approx. My friend who installed the motor adjusted the screw in the tb. I've read it could be timing, how do I check that? Also read it could be tps how do I check that? I could probably get my friend to check it but he just put in a lot of work and has other stuff he needs to go, any help or suggestions would be appreciated.

 

If you have your fott on the brake when this problem occurs it could be the vaccum system. I believe I am experiencing that scenario.

 

I don't think there's a vacuum problem, he checked for leaks and everything. If it is that, how do I tell?

 

I think we have the same problem... I spoke to a master toyota tech and he told me that it is not a problem. He said the way the system is designed, this sort of thing is normal.

The way you can test it is:

make sure everything is warmed up... push in your clutch pedal, shift to first, hold the break pedal, release the clutch 'till u feel the motor is shaking, then push the clutch pedal all the way back in.

now your rmps should be a little lower..

next shift into neutral, release the clutch pedal all the way, and press the gas pedal once (to raise the rpms to say 1k or above). When the rpms come down they'll come down higher than previously at idle... anyways, I was told this is normal due to the design of the vaccum system