ThurzNite

DLX JPP USA RCB T1 3VZE EFI MTM 5F IV3 R

314k miles

This's stumping me big time. Driving home, about to get off offramp, engine dies. I can't remember if I was lifting throttle or already in neutral. Start it right back up, it's in limp-home mode, barely runs.

Things I've changed:
Fuel pump with filters
Fuel filter
cat converter
Spark plugs (Did not change spark plug wires, but they tested very well)
Cap/Rotor
Distributor
Air filter
Mass Air Flow Sensor
Throttle position sensor (swapped whole throttle body)

Right now, if I set the rotor to 11-oclock position, and advance as much as I can, it'll fire up, but won't idle. If I set the rotor to sparkplug wire #1, it'll crank but never catch or start. I'm hoping this isn't a big deal. The cams and crank TDC line up fine.

So with the rotor at 11-oclock, and cap/rotor/dizzy twisted clockwise, and Te1 and TE connected, it'll start, but won't stay running for more than a few seconds. Without the Te1 and TE connected, it cranks but doesn't start.

This's my work truck. No truck, no work, no money to buy food. Would love any help I can get! Thanks! BTW, I can take pics and videos for diagnosing if requests are made. Thanks!

One more thing: No check engine obd1 codes.

Jae

LittleBeast

rats in the air box?

LittleBeast

just kidding but why did you throw all those parts at it? what about a compression test? how many miles are on the thing?

ThurzNite

Regarding: https://www.yotatech.com/forums/f120.../#post51834948

I was getting a code for the MAF. I swapped it out with my friend's, and the code went away. However, that code was replaced with one for the TPS. Again, swapped out the TB so I wouldn't have to set the TPS. Now no codes.

In a very strange twist of events, it looks like I'm not getting fuel pressure again. Think the new fuel pump went bad. Thank goodness for 30day warranty. Will swap that out tomorrow, what a PITA!

So I'm finally getting air and spark, just need fuel. Which was the first thing I checked (and fixed?) originally. Grrr...

TNRabbit

Sounds EXACTLY like your VAFM is either bad or the wiring to it is suspect. Could possibly be a leak in the intake tube, too.

ThurzNite

Yup, just pulled code 24, 31, 32. Weird, I just swapped a known good one in the other day, ran better, and haven't touched it. Unplugged and reconnected, no change.

I'm still wondering about the fuel pump. I jumpered it at the diagnostic connector, I can hear the fuel pump, but no difference in starting. Then I released the cold start thing, and no fuel came out at all. The fuel pump is brand new, I hope I don't have to replace it. Any other way to test the fuel pump? For now, I'm going to detatch the hose from fuel pump to fuel filter, then jumper the FP again, see how much comes out.

ThurzNite

FP replaced, pressure back up. Starts, then dies. No codes. About to try starting fluid, then revisit the vafm.

Did compression test, within spec.

drkblu4runner

check your timing on your timing belt.... how long does it run for before dieing.... few revs?

drkblu4runner

o2 sensor? it does sound like your vafm is bad

drkblu4runner

woops just seen the "The cams and crank TDC line up fine" NVM

ThurzNite

Was swapped for a known good one. But I'll double check with ohmeter tomorrow.

TNRabbit

I'm telling you, this is a VAFM problem. As I said, may be in the WIRING to it. VAFM not working will not turn the FP on.

ThurzNite

I was thinking this too, but when I jumper the FP and B in the diagnostic, shouldn't that run the FP constantly? I've tried jumpering, and it didn't change anything.

What about the fuel pressure regulator?

JackedYota

I just had to replace the fuel pressure regulator on my 94 4runner today. It would idle but when you put it in gear it just bogged real bad and wouldn't move. I'm not saying it is or isn't the regulator just throwing my .02 out there.

ThurzNite

Thanks. How did you figure out it was the FPR vs the VAFM or TPS?
Dr J

JackedYota

I checked everything else that I possibly could and wasn't throwing any codes so I ripped the upper plenum off and when I took the regulator of something inside was rattling. Be sure that it is that though because the fuel pressure regulator is 72 dollars from autozone.

drkblu4runner

you can also cut a little off the fpr to get it off without taking the manifold off.

ThurzNite

Thanks everybody for the help. Truck is running now. This weekend I'll go over it in detail and smooth out the idle. But at least it's running again. Again, thanks everybody for the help!

thook

But, then, how do you get the new on? Cut a bit off of the tube on that as well? Did you have to cut the entire barb off, or just part of it?

drkblu4runner

i reused the old one. ya you would need to cut a lil off. idk about it leaking tho. mine has had no leaks for a year now