so a recently pick up a new to me 93 3.0 runner, took it in the other day to get it smogged(commifornia), they say the numbers are great but timming is set at 20btdc and they need to set it back to stock, so i give the go ahead and the do it and it passes, but at 10deg it runs terrible!! no power, off idle stumble, so i take it home grab my light and set it back to 20btdc and runs great again.

so what would cause this? slipped balancer? motor is remaned with less than 15k, no CEL.

 

i've heard the 3.0 runs better with advanced timing.
agree with the cali comment i used to live near Riverside. too bad, really nice state and weather, just screwed up people run it.
there is a thread on here about the 3.0 and things to look out for with them. search everything to know about the 3vz or 3.0.

 

It will run fine at 10, that's factory timing. If it doesn't, then something else is wrong. Set it to factory, fix whatever is wrong, then mess with advancing timing if you have to.

 

x2. Do you really think a bunch of anonymous folks on an internet chat room are that much smarter than Toyota's engineers?

 

I bet the timing belt is off a tooth or two. No way of knowing without tearing into it though.

 

X2 to fordless

 

make sure the throttle position sensor is functional, connected, and adjusted correctly. I had a helluva time getting my truck timed right the last time I had it torn apart. Couldn't get it under 12 degrees advance (ran out of travel @ the dizzy), and it ran like crap unless I cranked it to 20. Chased it all over the timing set and distributor, finally (re)checked the TPS and it was way off. Once I dialed that in I re-checked the timing and what was 12 degrees of advance was in the neighborhood of 10 degrees retarded.