Hey Guys new here looking for advice.
1990 SR5 4x4 3vze
Just put new timing belt, water pump, oil pump,and idler pulleys on and the thing runs great twice the power than before. Installed a thermostat ( it didn't have one before) and new exhaust from the cat back. Ran great for a week, but now if i drive it more than five minuets and turn it off it wont start back up.I just get a faint click from what i believe is from the starter relay in the fuse box under the hood marked EFI. If i let it sit for an hour or so to cool down it will fire right up no problem. Replaced the starter and the starter relay already still the same. Could installing the thermostat have anything to do with this problem?

 

Nothing wrong with your starter nor starter relay. Thermostat has nothing to do with it, either.
It's the wiring: https://www.yotatech.com/forums/f199...l#post52368225

If you'd like us to help please put us under your hood; let us see, hear, feel what you see, hear, feel in front of you.

 

Sounds like possibly an intermittent open or high resistance connection (caused by heat?) between the starter/solenoid and the battery.

RAD4Runner, I was going to supply him with that link to your thread as well! Lots of useful information there.