3VZE problems

Having problems with my V6. Dont know if anyone has any knowledge on this type engine but i'll give it a shot. The truck idles fine and everything but when i go to give it gas the truck just bogs and then slowly increases RPM's. When i take the truck out and put it under a load the truck doesnt want to move anywhere if i floor it, all it does it bog out. If i slowly press the pedal its fine until its all the way down to the floor. Its like it isnt getting any gas or anything. I've replaces fuel filter, TPS sensor, MAF sensor, ECU, spark plugs, wires, dist. cap, rotor, cold start injector, and even cleaned the injectors. Im beginning to think it may be my injectors that i didnt clean them very well, or my fuel pump is going bad but i dont want to buy things i dont need. Hooking it up to a computer helps none because all my emissions shit is capped off. I get about 15 different codes when hooked up. Anyone have this problem or heard of this problem?

it could be vaccume leaking from somewhere... i dont know much about the v6 but that would be my best guess.

You should have a schrader valve (looks like a tire stem valve) on the fuel rail, hook up a pressure gauge to it and see if you have enough fuel pressure.

Could be a vacuum leak as jeff said.

Double check all your grounds, maybe relocate them to different areas.

Check to make sure fuel pump is actually turning on. Some engines can still draw a little fuel without the pump working.

no vac leaks, fuel pump works well, i've rebuilt the entire engine and its finally all back together, all new grounds, everything has been either replaced or redone, it did it before the rebuild too, i thought it was the TPS sensor so i replaced it and set it to correct specs, new pressure regulator and everything, i'm about fed up with this bitch not running right, on the fuel rail there isnt the valve to read the pressure, i've looked before and no luck, i've tried running the pump with 12 volts constantly and still no luck, tried taking out the fuel filter and running and straight fuel line, no luck, have been through 3 MAF to see if they made a difference, 2 computers, i remember it used to be really bad and came out to be my alternator was bad and i was running off my bat. but replaced that and its pushing a good 15 volts to the battery, i have no clue and dont want to take it to a dealership to mess with it because they'll just hook it to a computer and tell me whats wrong and that like 15 codes popped up, i can do that right here in my garage for free

my 3vze did the same thing... make DAMN sure, (and look HARD) that there are no rips / cracks / tears in the rubber air intake tube that hooks to the throttle body...itll look fine, but when you torque up the engine (like flooring it) it will twist the air intake tube between the mass airflow sensor and the throttle body, and let additional air in, causing it to bog like hell.... but its fine when you accellerate slow, because it dont torque and open up the crack in the tube.

you will have to take it off and inspect it , twist it and bend it to find a crack, otherwise it looks normal.- hopefully this is your problem too

I'm just trying to cover some basics.

Does the timing use a CPS, crank position sensor? I'm not familiar with the electronics on these motors,

Is the fuel pump for the original 4/6 cyl? When you straight lined the fuel (bypassed the factory in tank pump) did you use an aftermarket inline electric fuel pump?

Have you done a pressure leakdown test on all 6 cyl.?

If memory serves me right, these motors were prone to blowing head gaskets worse than the 22r series. When you had the block torn down, did you resurface the heads and the deck? Have the heads been magnafluxed (checked for cracks)if not did you use a stock/ OEM style headgasket?
Reason I ask is that in the past when I have had trouble with motors blowing headgaskets I usually went with a thicker than oem style gaskets or an all copper style.

When you put the motor back together did you replace the head bolts or re use the originals? After so many miles the head bolts get stretched, scalded and basically uesless. When you go to reuse them they will torque down but over time they "stretch" more than they should.

it could be a bad cat also! or do you even have one? just amke sure everything it tighten up in there as toyotaman stated!

head gaskets have been replaced with OEM style gaskets, i havn't looked over the air filter just yet but will do that today, there is no cat on the truck because one wont fit under there, my exhaust is done in retangular box tubing because the regular round, circle piping hits the ground, i was also thinking that it could be my O2 sensor going bad, theres so many things that could be wrong its just pissing me off, and also all head bolts have been replaced, this problem happened last year, i was welding on my truck and after i was done welding it happened right when i started the truck from that minute, i thought i might of fried something electrical so i replaced the computer, didnt help and then the TPS sensor and MAF sensor, today i'm going to try and retard the timing a lil and see if that helps.

hmm, right after welding on it ehh? Thats something thats really sucks these days on computer controlled vehicles. You may have reversed the polarity on some sensors or damaged the battery and alt. if they were still hooked up.

thats the thing, i've replaced the alternator because it did go out and even blew the big ass alternator fuse, i replaced the battery as well, and the TPS sensor, im checking the fuel pressure from the fuel pump today, i'm beginning to think it may be that or the O2 sensor.......hopfully