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Discussion Starter #1
Truck was doing great, just needed the brakes & the steering bled.

Got all that done & the damn thing started acting up. Hard to start, loss of power sounded real familiar.

Checked all the vacuum lines, found & replaced all suspect lines. Found the pcv valve cracked & replaced that. Found a broken wire on the maf plug soldered that back together.

Pos runs really good, then all of a sudden falls on its face. Checked the gas tank by removing the cap, no vapor lock. Truck won't start again! Wait and truck struggles to start but then starts. Runs like crap, then begins to run better. Then start the whole process over. Poor performance, barely runs, gets better then sucks again!

There's no rhyme or reason. Connor & I spent entire day trying to figure it out
 

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Did you ever get your charging system taken care of? My truck had been doing similar stuff for the last year.....then last week smoke began pouring out of the alternator
...replaced that and the running issues went away....apparently the low voltage was messing with the engine control system
 

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Discussion Starter #3
The charging issues are taken care of. Like before though I/we get the feeling it's either electrical or possibly fuel delivery but at this point I feel we're just pudding in the wind.
 

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This is going to sound really stupid, but my buddies 4runner was doing the same thing but...... Does it have enough gas in the tank?

We had an ob2 scanner hooked up to it, checking voltages on all the sensors, checked the vacume lines, and the truck was still sputtering and running like shit, even backfireing!! Turns out it was low on gas and the truck wasnt happy about that.
 

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That was an early thought, but I had just put in 5 gallons of gas before test driving.
 

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fuel pump is external. I am thinking it maybe due to the pressure regulator. It is one part I never switched because (sounding stupid here) but I never found it. I heard somewhere that toyota left the regulator off some models of my truck which makes no sense to me.

but that is my direction to go in. put a fuel pressure gauge and new regulator on and see where that takes me.

the new tank does have baffles in it. and the current fuel level is just about level with the top of the boxes. I was also thinking that maybe the fuel level is preventing a proper priming of the system.
 

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Bear, you still have the 3.4L, right? If so, the fuel pressure regulator is on the firewall side of the driver's side fuel rail. You have to remove the intake plenum (not sure if the supercharger has to be removed) to access it. With the supercharger, I believe you should have a vacuum line on the regulator that increases pressure as the load increases (from the factory, there is no vacuum at the regulator). Since it's hidden, you might not be able to see if the vacuum line is in good condition.

If you have access to the fuel pressure gauge SST you could verify any fuel pressure issues. If you have time, here is a good mod to add a fuel pressure gauge. http://www.samsonfab.com/phpbb2/viewtopic.php?t=10

I'm getting ready to replace my regulator. My fuel pressure has been running around 30-31 psi. Factory specs are 38-44 psi. I'll also be sending my injectors out for testing/cleaning while it's apart.
 
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