my 91 toyota 3vze had a burned valve. i had another engine i removed the heads and delivered them to the cylinder head shop.when i picked them up he did all the usual and set the valve lashings.when i reassembled my engine the it ran like crap. (i.e would not idle, backfire through the intake). i triple checked my timing and its perfect.my muffler ig getting extremly hot at idle.what could it be.

 

did you check the timing with the connector terminals shorted?

 

Stuck intake valve? Have you checked compression? Not too familiar with the 3vze but is the timing belts setup correctly on the pulleys? If it was me, I'd double check that stuff first. Good luck.

 

Maybe you got a couple of plug wires crossed.

 

I just have to mention that the title made me laugh, I am sorry, move on ...

Marko

 

A backfire usually indicates a timing problem.
Check the timing belt and distributor timing (firing order and advance) again to ensure you didn't miss something.

 

simply put your timming is off......

 

backfiring could most definitely be caused by an intake valve that's stuck or doesn't have enough lash(and thus is staying open)

 

thought the same thing...

"simply put your timming is off......"

maybe her timing is off...jk.

 

ok i solved the problem it was a leak in the intake gasket

 

bloops! i've made that type of blunder before. after i swapped in my 20R head, i fired it up and it ran like total crap. yanked out the timing light and it was a *little* off but setting it to spec didn't help.

ended up, i noticed that i had forgotten to connect my brake booster line. doh!