1998 2.7 Tacoma

I was driving my truck a few days ago and it was running great. Stopped at a red light and went to take off and it would only go if I lightly pressed the gas. If I rolled into it the truck would sputter and barely accelerate. I noticed the truck was really low on gas so I stopped and put some in and it didn’t help any. I got it home and now I can start the truck and it idles fine but if I try to give it any gas even in neutral it sputters and backfires.

codes pulled:

p0441
p0446
p0171


the 441 and 446 have been on for a while. The 171 system too lean code is new.

I have the lce fuel pressure gauge on my truck at the FPR and it shows 46 psi even if I try to rev the engine. The pressure does not change. Based on reading I assumed it would be the FPR so I replaced it with a used OEM unit and it did not fix the issue. I’ve unplugged the MAF and started the truck and it immediately dies. Unplugged the TPS and runs erratically.

im at a loss on what it could be and any help would be appreciated. The truck is not even driveable at this point in time. At idle the truck runs fine but any pressure on the gas pedal now and it stumbles and backfires

 

It could be that yes, you have good fuel pressure, but do you have good VOLUME?

When you ran the fuel way low, it's possible that it picked up some trash out of the fuel tank. It may be that the filter, or a fuel line, is partly clogged. It will show good pressure, but is you flow rate adequate?
Easy enough to check. Pull the return line, put a piece of clear tubing on it, and put it into a measuring container. Run the fuel pump for a minute, and see what your volume is. I believe it's supposed to be 0.5 quarts per minute, but that might be pints, not quarts.

If your volume is adequate, could it be a clogged injector or two?
How about the knock sensor, or it's pig-tail? Or what about the O2 sensor(s)?

I'm not real well versed in the 1998 Taco, so those are my only two ideas. I'm sure the true experts around here will pop in and tell you exactly what the problem is. They're quite good at that.

Good luck to ya!
Pat☺

 

I don't know much about the 3RZ(I think that's the 2.7l?), but the first thing I would look at is the two codes that it has been throwing for awhile. I would think that whatever is causing it to throw codes could definitely lead to some running issues.

 

I forgot to put it in my first post but I replaced my fuel filter at the same time I replaced the pressure regulator. I’ll try to do a volume check tomorrow but it’s snowing and cold as hell outside so I may wait til it warms up a bit next week. It’s not my daily so I can be without it for a while

 

what was your answer?! what was the fix?? I know it has been 5 years but i am about 6 months in and have replaced every sensor, i have a 1997 2.7, I am having the exact same issue.

 

welcome