ive searched the threads and cant find my specific problem so here goes i have a 94 4runner sr5 3vz5 speed 4x4. heres the problem: it starts and idles fine, if i gradually increase the throttle it will rev up as expected TO A POINT(about2k rpm).at that point it bogs down and damn near dies. if i rapidly increase the throttle it will do the same. there is no check engine light. ive read threads about these doing something similar when put in drive (obviously on autos) or something having to do with the circuit opening relay but from what i understand if thats defective it wont start at all(correct me if im wrong) but nothing that matches my situation. ive replaced: tps(set per service manual resistance values), cap, rotor, plugs, wires, afm(also verified resistance per service manual values), i checked impedance on all the injectors and they all have identical resistance, oil and oil filter, i also have a 94 pickup sr5 5 speed 3vz so i took the ecm out and put in in the runner to check(did not fix it) also swapped the efi relay from the pickup it does not overheat but does take a long time to come up to operating temp. i used a mechanics stethoscope to listen to the number 2 injector which gradually increases frequency as the rpms rise but when the motor bogs the injector stops firing. hopefully someone can give me some insight thanks

 

Make sure you installed and set the TPS correctly... not familiar with the V6 but, on the 22re you can UNPLUG the TPS with those symtoms, and if it will rev up normally with the TPS UNPLUGGED then the TPS is bad or out of adjustment.
fuel pressure regulator can cause the symptoms your describing...
try to determine first if it's a fuel or fire issue cutting your search for a fix in half.

 

Thanks for the reply I installed the tps correctly and adjusted it per the service manual as for fuel vs spark it's a fuel issue since the injectors stop firing when it's bogging

 

Unplugging the tps makes it run worse so that's ruled out. The fuel pressure was high bouncing between 45 and 50 psi so I checked vacuum to the fpr and there was none. Put a vacuum pump on it and the fuel pressure dropped to 36 psi well within spec. Turns out vacuum lines were crossed so I fixed that and now there's vacuum to the fpr. Today I'll check the fuel pressure and see what it does at the rpm the engine bogs. What mechanism causes the injectors to stop firing around 2k rpm?? I'm stumped could the injectors be faulty even though they're within spec for impedance?

 

Sounds like "limp" mode... any codes?

 

The only design aspect that cuts off the injectors is the lack of the IGF signal from the igniter. But that requires several crank revolutions, and it's hard to imagine an IGF failure that is rpm dependent.

Having the vacuum to the FPR mixed up will definitely cause rpm related bogging. Have you tested it since "fixing" that? Are you sure you fixed it? (The vacuum routing is on the under-hood sticker.)

Ignition timing will also cause your symptoms; have you checked that?

 

No check engine lights I rerouted the vacuum lines according to the sticker under the hood and checked vacuum at the fpr and it's showing 20psi I haven't checked fuel pressure since I did that but when I did have the fuel pressure tester on I applied 20lbs to the fpr with a vacuum pump and the fuel pressure dropped to 36psi spec is 33-38 so that's good as far as the signal generator I put the distributor from my 94 pickup on it to check it because it runs fine thanks for the input

 

I did time it but not at 800rpm I'll have to redo it how does it go into limp mode and how do I get it out?

 

Also put the coil from the pickup on the runner but it didn't fix it the ignitor is on the coil correct?

 

Got the exactQUOTE=greenpig;52458734]Also put the coil from the pickup on the runner but it didn't fix it the ignitor is on the coil correct?[/QUOTE]
Did you ever figure it out? Help some one! Going to loose my mind!
Me