Newbie 2nd Generation member

And could use some expertise in diagnosing an 3vz-e engine problem. I just had a shop rebuild my engine in Jan. 2023, in lieu or replacing the head gaskets for the 4TH time, (496,000 miles), considering a complete head vat, grind, surface & deck was required. Included, all parts OEM from YotaShop.com , : NEW pistons, rings, freeze plugs, multi- gasket, O-ring, seal sets, head gaskets & bolts, valve covers, timing belt, water pump, pulleys, tensioner, oil pump, fuel pump, fuel filter, salvaged fuel tank, fuel damper assembly, muffler, distributor, plugs, plug wires, battery, bearing sets, thrust washers, vacuum hoses, new aftermarket Mass Air Sensor, used ECM replacement, break-in oil/filter change, etc, etc

My 4ruuner starts, idles, and runs fine, BUT after running and warming up - engine starts sputtering and stalls upon braking to a stop, or making a slow 90* turn. I can quickly shift to neutral, & give it excessive throttle, and it starts right up and runs as long as I give it excessive throttle, including when I have to brake to a full stop. Prior to this behavior, for several months, it's 'Check Engine' light came on while driving a few times-But not every time, but after turning engine off and restarting - NO 'Check Engine' light, and didn't start stalling until now.

What could be it's problem? What to consider is the cause? Any input would be appreciated. Bobby

 

Welcome. After it is warmed up, what is the idle speed?

 

Appreciate response,
normal just like after startup/warmup, tach reads 10-11 RPM range but before stalling in neutral, idle drops to 8-9 RPM and then stalls, UNLESS I throttle IT to stay above 10 RPM.

 

Normal idle is around 850 so that's sounds like you are there. Sounds to me, I'm no expert, like it's a fuel starvation issue. Hopefully someone with more experience will chime in soon. Also check all your vacuum hoses to make sure they are attached and routed properly.

 

Also trouble shoot your throttle position sensor...

 

For what it is worth...not an expert.
things that I would check.
Fuel filter
sounds like a coolant sensor problem.
coolant temp sensors on manifold behind intake plenum.
Do you have air pockets trapped in your coolant system? That will cause problems.
vacuum leaks (Ive had problems with power steering pump vacuum, there are 2 hoses)