1st Gen Overheating (3rzfe)

Hey all,

Recently changed my head gasket on the 3rzfe. Drove around for about 500 miles incident free (sub an annoying exhaust leak I haven't been able to fix). Yesterday I blew a P0325 (Knock Sensor), and this morning I started overheating (up to 111C, I typically run at 85-90C).

Truck's performance before overheating was noticeably worse than a few days ago (took 15%-ish longer to get RPMs up, A/T transmission shifting at slightly later RPMs).
I'm a little stuck on what could have happened. I think I lost a little coolant during the drive as well. Plan on doing some diagnosing today but unsure of where to start. Anyone have any advice?

Thanks,
Dave

 

Are you sure you check that head carefully....


https://www.tacomaworld.com/threads/head-gasket-leak-advice.806585/#post-29071376

 

Yeah, took it to a shop to get it resurfaced/leak down test/valve job. Ran a compression test after everything was put back together and got 190 psi across the board.

 

There could be lots of reasons;

Did you replace the thermostat?

Did you burp the coolant system?

Did you add any additives to the coolant system to fix the old head gasket leak and now the radiator is clogged up?

Knock sensor should probably have been replaced

 

Process of elimination......crack would of been worst....

everyone ones gonna ask same questions.....

oem thermostat , and jiggle in right position...

water pump......fan clutch....engine temp sensor....

how many years on that radiator......


Egr stuck/messed up....that keeps it cool at highway speeds.....



Drive around with a decent scanner and watch live data for all these...
see which one goes wacko first.....

 

I replaced the thermostat, water pump, ECT sensors. I believe I burped the coolant system but it is possible there's an air bubble somewhere - I didn't get it on a ramp or anything. I agree about the knock sensor...
I'll do some fan clutch/egr investigation. Thanks for the tips.

 

Long shot....but are you sure you're getting a good ground on the head and block....
the plugs need a good ground.....

These trucks come from factory with a body sheet metal ground....really high quality stuff....

 

Well my water pump is leaking profusely. Not sure if it's just a bad part or I did a shit job with the RTV... Thanks for the help.