scottishb

The 4Runner has been acting up lately. It's sitting in "time-out" right now. Why? Sometimes when I hit the gas pedal nothing happens. I have to give it a pretty good amount of pedal to get it to kick in. Other times it takes off just fine. Is this what happens when the TPS is going out? Is that what that plug is by the TB?

Fink

When was the last time a full tune-up was done it?
Oil, filter, air filter, plugs, fuel filter...

My money is on plugs - use OEM.

Fink

scottishb

I got this truck last September, so I am not too familiar with it. It doesn't feel like a spark issue, though. It feels like a fuel pressure or a sensor thing. Fuel filter sounds like a plan. But I really think the TPS might be the culprit. I'll put the pedal 1/4 way down, and it doesn't chug, it just waits a second and then takes off. And then at the next stoplight it'll act normal. It's intermittent. I dunno...

scottishb

So I took it for a ride, but this time I didn't turn on the A/C at all. It didn't act up at all. Hmm.

gdutch

That's very strange. It does sound like a spark issue to me, so it could be coil packs, plugs, or wires. Any CELs?

scottishb

No CEL.

Fink

If I were you I'd just start doing little regular maintenance things here and there - regardless of the A/C making it worse.

I'd clean the throttle body and MAF, check the air filter, replace the fuel filter, etc...

Fink

rtn

I had the same symptoms. Intermittent / sporadic hesitation; sometimes no response when pedal was pressed; no CEL. Turned out to be the TPS. On my truck, the whole TB has to be replaced! Fortunately that was covered under warranty. New TB made the truck run like new.

2004 Tacoma 4WD TRD MT 3.4L

LifterCatcher

I also have the same issues, not as bad but it does the same thing. From the little research that I have done TPS seems to be the culprit. I will be doing everything that Fink posted plus the TPS calibration posted by 4Crawler.com I will report back with my findings

Beto

Are you sure if you give it enough pedal it goes - or does it just go after a few seconds anyways? Does it always happen from a stop? No other bucking/surging/hesitation issues when the truck is already moving? Have you noticed that it happens more when you want to turn from a stop? And the biggest question, does your '01 have VSC and TRAC?

If the answer to many of these questions is yes, it is probably your VSC system acting up. You can try a zero-point-calibration (this didn't help me) or test the "Andy Mod", the "Bagel Mod" or the "Bagel Mod Light" to see if it goes away. Also note that the VSC system might de-throttle your engine on you without giving you that "beep-beep-beep" noise.

I like the Bagel Mod, but then again, I designed it so I'm not really impartial. If you can live without ABS for a few days, pull the sensor wire off the master cylinder to trip a fault for the ABS, TRAC and VSC systems. This will turn them off until you reconnect the wire and turn the ignition off and on again. (see the first post in the last link below - it has a picture of the master cylinder with the wire I'm talking about disconnected). If it does help, please remember that the VSC system is the only one that might be causing your issue. The TRAC causes other minor annoyances, and the ABS I find very useful. With that in mind, decide if, and which of the 3 mods you want to do.

Here are some links to read about the problem and the mods:
https://www.yotatech.com/forums/f2/andymod-2-0-abs-remains-active-204623/


https://www.yotatech.com/forums/f2/new-improved-andy-mod-real-trac-off-switch-195040/


https://www.yotatech.com/forums/f127...ystems-103814/

More info:

Andy Mod - Like pulling the sensor wire but on a switch. Easiest to do. Disables ABS TRAC and VSC.

Bagel Mod - Allows you to turn off and on only the VSC without turning ignition off and on. Also allows you do disable VSC and TRAC (leaving ABS active), but you need to turn ignition off/on to re-enable them. Hardest to do. Requires several relays, electrical knowledge, and patience.

Bagel Mod Light - Allows you to turn off VSC and TRAC leaving ABS on. Must turn ignition off/on to re-enable. Cannot turn VSC off without turning TRAC off. A little tougher than the ANDY Mod, but nowhere near as complex as the full Bagel Mod.