5VZFE Refuses to Stay On/Idle

Hey y'all! Pretty new to the forums but pretty stumped on an issue I'm having with the 5VZFE in my '91 Pickup. As the title of the thread says, I've got a 5VZFE that just refuses to stay on or even idle past 1,000 RPMs. So far my old man and I have replaced the fuel regulator, cleaned/checked the MAF, TPS, and IAC, fuel pump + filter were done a year ago, and even checked my igniter just in case. Still no luck. Our next stop is to grab a fuel pressure test system from AutoZone since we're not getting any sort of codes either...does not like when the gas pedal is touched and sounds like it grabs more air than fuel. Pretty stumped, but would love to get the ol' girl back on the road and turning heads at the beach. Thanks in advance y'all!

 

I would replace the fuel filter again. Bad Gas? Always that chance.

 

Dang that'd be three times now on fuel filters BUT could be that...I fill up on a reservation with cheap prices (possibly bad gas?) however our diesel and my momma's Corsair have never had a problem with their gas. Still going to make a run for that fuel pressure kit and report back.

 

Have you scanned it for codes? You might get a pending code for either crank position sensor or cam position sensor with symptoms like that

 

Ran the code reader right before the fuel pressure test and ZERO codes, however we ran the pressure test and we're getting 0-5 psi so we're leaning towards the fuel pump and filter...first time I've had a Quantum pump go bad on me within a year. Total bummer if that's what messed the truck up.

 

I usually get aeromotive pumps, but I've definitely bought other stuff from quantum fuel systems that's been good quality too.

 

On my 93 I found the "swinging door" part of the MAF was jammed halfway open for some reason

Is the rubber boot ripped between the maf and throttle body? Did you do all the sweep tests for the TPS and MAF?

Edit: nvm, just saw you said 0-5 psi fuel pressure..

 

I'll give em a look! Gonna take advantage of the lifetime warranty with Quantum while I'm at it as well.

 

I'll add, I also have the K&N setup on my 5VZ...not a HUGE fan but we have a feeling that MAF may be on its way out. Doesn't seal very well against the plastic either so I may end up fabbing a custom setup to have that sensor sit flush.

 

Cool looking truck tho. Are those 37s?

 

What year Tacoma is your engine and wiring harness from?

 

You won't believe me, 33s! Currently on 33s with 16" beads

 

2001 my man, however to my knowledge my old man says the ECU is from a Tundra? Gotta double check that.

 

I was way off, looks great though.

Also I thought you had the old 3.slow motor. Totally different maf setup.. anywhos..

 

Yeah I've heard horror stories about them, not down for that at all hahaha. This thing had the 22RE prior to the swap.

 

Oh okay, I have a spare mass air flow sensor for a 95 to 97 Tacoma I was going to offer you. There were some 5vz tundras, kind of rare beasts.