Auto trans disengages when pressing gas pedal at mid speed

Greetings! 2014 Tacoma PreRunner Quad Cab V6 SR5, 5-speed automatic. 26 miles new, 1400 now. When traveling freeway speeds (70+) and slowing for traffic to 45-60 for awhile, when then pressing gas pedal to gradually accelerate, feels like putting in neutral and coasting. Engine idles down. Holding pedal there does nothing. Letting off and then starting to push down results in slight engaging for trans/engine, but then nothing again. Can keep pressing on/off/on to gradually get it going faster, then finally back to normal. Sporadic, unpredictable, cannot duplicate when trying. When in this coasting mode, pressing pedal to the floor finally engages tranny in low gear pegging tach. Trans seems to lose track and not know what to do. Took to dealer, twice, happened once in a drive-along. Did a software upgrade and reset the trans memory. Still happening every few days when in that scenario of slowing for traffic, etc. No codes thrown! Hard to believe that. Dealer will open a case with Toyota next time it happens. Any ideas? Thanks,

 

Does the engine rev but the tranny doesn't engage? Have fluid level checked. There's been some people who had low fluid in new trucks. I still need to check mine. Sometimes when it's cold it seems to slip. It's acted like that since I bought it new.

 

Thanks. No, engine doesn't respond either, as if neither the trans nor engine know the gas pedal was pressed. The dealer checked the fluid.

 

Almost sounds like a bad throttle position sensor. Can't imagine it would be with it being new. Certainly seems like a signal problem of some kind. These trucks are drive by wire.

 

I agree it does sound like the sensor for the pedal. New parts break as well as old parts.

 

Sounds reasonable, but they can't find anything yet. Works perfect all other times. A friend had a mid-90s Camry that acted similarly. Turned out to be an ignition switch-related issue. Not sure how that would work.

 

Did the techs at toyota look into anything other than a cel? I know sometimes they contact Corp to see if there is any related problems to give them a starting point.

 

Supposedly they researched. But they will open a case with Toyota next time and they said Toyota will send someone out to check it.

 

If they say there is no problem take the service writer for a test drive and show him the problem and keep documentation with dates and times in case you have to lemon law them.

 

That's good at least. Some people go in circles with their dealers trying to get some help with an issue. Yours sounds like they're helpful.

 

Actually, the Service Manager went with me and he is the only one who has witnessed it. After two times there, he actually used the lemon word as a possibility. I have to admit that they have been great so far in trying to help. Gave me a rental last time. Now they just need to fix it.

 

That dealerships a keeper.

 

Another possibility is a faulty or misadjusted brake pedal switch. Since it has the "accelerator override" feature, it could explain the loss of throttle response, and the other symptoms surrounding it.

 

Yeah, there have been a couple confirmed cases of brake switch problems causing loss of throttle response here on TW, and a few more suspected cases that never had an update to the thread. It can be hard to tell if your brake lights are on when you're driving, but you could try depressing the brake pedal to see how far it travels before the brake lights illuminate (have a helper watch the lights) If it travels less than 1/4" before the lights come on, or if the brake lights come on when wiggling the pedal side to side, you've probably narrowed down your issue.

 

The software upgrade they did to your truck ..... did they explain to you what the purpose of the software upgrade would do ?

Check your service records using your Vin # and it should show you what the software upgrade did . Here is the link http://www.toyota.com/owners/web/pages/home

Keep us posted on this one .

 

When i got my truck my feet would sometimes hit the brake and it was a really weird sensation. Or be braking with my foot on the gas pedal. They layout the pedals in these trucks strangely.

 

Thanks, all, for the suggestions. The dealer tech did ask if I had pressed the brake pedal prior to the issue happening. In the slow traffic, I had tapped it a few times. I'll have someone check the break lights when I press the pedal. The software upgrade had something to do with the transmission, but not exactly my symptoms.

Here's what was on the service invoice for the work performed (thanks for the info on how to find it online):
DRIVEABILITY ~|~CUSTOMER STATES WHEN ON FREEEWAY AT 65 MPH AND DECELLERATING WITH FOOT OFF GAS EPDAL THE TRCUK WILL COAST NORMALLY WHEN GAS PEAL IS PRESSED TO ACCELERATE THE TRUCK WILL FEEL AS IF TRANSMISSION IS NOT ENGAUGED. NO POWER AND SEVERE HESITATON . WHEN GAS PEDAL ~|~VEHICLE SHIFTING NORMALLY HEARD PINGING KNOCK ON LIGHT ACCERATION FOUND TSB 0044-12 ~|~2157 PERFORM TSB - 0044-14 UPDATE ON ECM. RESET MEMORY AND ROAD TEST - OPERATING AS DESIGNED AT THIS TIME.

As for cruise control, it has never happened with it on. But I have never had the scenario - slowing, staying at the slower speed, and then accelerating - with the cruise control on. When it's happened, I've tried many combinations of things to try to isolate a cause: shifting from D to 4, radio on/off, A/C on/off, etc. Nothing makes a difference. So far your suggestions of throttle sensor or brake pedal switch (accelerator override) are in the running.

 

Quick update on the issue. After being fine for a couple of weeks, it happened again big time yesterday. Trying to pass a car on a 2-lane road, it "paused" just as I pulled out. Had to brake and get back in behind the car before I got hit by the oncoming car. Kept happening all the way for 30 miles. Called and opened a Case with Toyota. Will hear back tomorrow about next steps.

 

sub'd

 

Why do you link that picture of your truck on every post lol


Just put in a sig pic