Stalling out, moving gas pedal recovers it

So I've got a new problem with my '07 5 speed 89k miles. It's the first problem I've had actually, and here's what is happening.

Driving along, and it feels like I took my foot off the gas. No popping, sputtering, etc...just no acceleration. If I either lift or push further on the go pedal, it catches and starts accelerating again. This has now happened with engine, hot, cold, up hills, and down etc. Completely random and speed irrelevant. Lift foot or push down, and off I go. No check engine light when this happens.

So far, have cleaned throttle body (which was really pretty clean), MAF sensor with CRC maf cleaner, checked and re-gapped plugs which looked nice and brown, gap at about .046 so brought down to .043. Air filter clean.

The result of the maintenance is a truck that does actually run a bit better, but still have the cutting out issue.

I've searched high and low for a similar situation, and unless my google skills have failed me, can't find a fix for this. Any ideas on where to look next?

Thanks,

Mark

 

So I missed this thread, but unfortunately didn't see you had a resolution. Did you get it fixed? Mine doesn't go out for 20 seconds, and comes back as soon as I move the pedal (so far at least), but otherwise sounds like what you had happen.


Mark

 

yeah, misery loves company Mine is doing it every time I drive, so a bit more concerned. Hate to take it to a dealer at this point, as it sometimes takes a while to happen, and it isn't throwing a check engine. No doubt, nothing will be found...

 

I wanted to clarify something before I try to offer any help. You mentioned in the title that your truck stalls out, then catches when you change the gas pedal position, but then you mention "Just no acceleration".

Stalling out means typically that the engine stalls, or dies. Can you be a bit more specific? Does the engine just act like the accelerator has a "dead spot" where the engine just hesitates and has no acceleration, or does the engine actually attempt to stall, with the RPMs going under 750?

 

Good question and something I checked yesterday. It actually doesn't stall, just drops down to idle. Checked it a few times with the same result...revs down to about 750. So if it had a throttle cable, I'd think the cable snapped.

So I kept checking things and think I have actually solved this. Was going to wait another day or so before posting, but will be optimistic that it's solved. I pulled the brake light switch out, took it apart, cleaned the terminals and remounted and no longer hitting any dead spots. Clue was that brake lights were on briefly while I was out of the truck, so figured switch was messed up. Don't know the exact electronics of why this would cause it to drop to idle, but guessing has to do with unintended acceleration issues and protecting me from crashing into things if the pedal was stuck.

If the brake light switch fix isn't it, will post up accordingly. But based on the dead spot issue, any other ideas of what could cause this behavior if the problem does come back?

Thanks,

Mark

 

Well to be honest, I don't think your brake pedal switch has anything to do with your problem, but hey, with todays electronics, you never know. I would actually suspect something more with the APP sensor.

 

Mystery to me too, but have now driven quite a few miles without a hiccup, and it was happening probably every 1/4 mile. Was thinking maybe bad gas in the tank, but the fact that it was dropping to idle rather than stalling or sputtering ruled that one out in my mind.

I've shopped prices on the APP sensor and throttle body/TPS and figure they're next.

Thanks,

Mark

 

My 07 vw gti was drive by wire. If you touched the brakes the throttle would drop to idle even if the gas pedal was floored. I am pretty sure its the same with our trucks, and most other drive by wire vehicles.

 

It's been a few days now, put in new brake light switch this morning, and no problems. So strangely enough, it appears that the brake light switch was the issue.

Related to this, had ordered a bluetooth obdii sender and will try to get that working with my droid. Curious to see if any DTC's or otherwise show up, but relieved that my Taco is running strong once again.

Thanks for all the input.

mg

 

While I believe this issue is resolved, I purchased a bluetooth obd ii bluetooth adaptor elm327 for $19 off ebay, and torque for the droid. It hooked right up, and not surprisingly no error codes thrown out. For $24 total having the obdii diag tool as well as other cool features is money well spent imo.

 

Agreed. Mine should be here monday!

 

I was a click away from buying a $200 obd ii diagnostic tool when I tripped over the thread somewhere on my TW search about the blutooth setup. Amazing that something can do that for such little $s. Now I just need a hands-free mount for the phone or smokey will be pulling me over here in CA

 

I seem to remember reading something on this (in my manual or online???) anyway it was a comment on how the computer would check the brake and accelerator to be sure only one was on at a time. Or in other words - so you won't ride the brake when driving down the road. I think it said that it would drop the engine rpms to an idle if the brake was on when the accelerator was still depressed.... Does this sound familiar to anyone????

 

don't recall seeing that in the manual, and I have read most of it, but it is exactly what mine was doing. I did try dragging the brakes while driving and it didn't cut the throttle to idle when I tried it, but I'd imagine there are more variables than what I was doing. Whatever the case, it does seem that there is a tie in to the brake and throttle cut out.

 

http://blogs.cars.com/kickingtires/2010/02/toyota-to-add-brake-override-system-on-all-new-cars.html

"How does Toyota’s brake override system work?
It’s an electronic system that engages when both accelerator and brake pedals are depressed, then the system cuts engine power: “When the vehicle is moving and both the gas and brake pedal are pushed at the same time, this software forces the vehicle to respond to the brake only,” Toyota explains in its recall FAQ. Lee said it will work under all conditions — not just in extreme situations — so those who drive with a left foot on the brake pedal will have to learn not to do that.
"

 

I am having the exact same problem. 2009 DC Sport. I was having some issues with the ABS light and Traction Control lights coming on intermittently, and had the brake light sensor replaced (because the dealership said it was spitting out a code for this). Ever since (it's been a week), I get this same symptom- the accelerator just cuts out and RPMs drop, but if I pull off my foot and put it back on, or pump the pedal, it comes back. Interestingly, I have also had a few times when the car is parked and the brake lights just turn on (with nobody in the car). Sounds like I got a faulty brake sensor.

 

what you describe is exactly what mine did. Lights on when no one in the car, cutting out random and then came back. New brake light switch fixed mine. Though I didn't get a code even when cutting out, so maybe the 09 has a smarter obd sensor. Either way, cheap fix and easy enough to try.

 

I had just had a new brake sensor put in, but apparently they didn't adjust it correctly. Following someone else's remarks, I was able to pull it out (1/4 turn) and re-install it adjusted up a little bit. No brake lights coming on for no reason any more, and no more interference with the accelerator.

All good.

 

Back in 2012 purchased a new Tacoma automatic six cylinder. SR5. Loaded. It did same thing. Dealer couldn’t fix it after leaving it there for two weeks. Pull up to stop sign. Take off and it would go to idle. Let off gas few seconds and act normal. I asked them bout changing some parts but said unless computer showed it bad couldn’t replace it. Here’s the hard part to believe I traded the truck in on new year model. Limited. It did same thing. They couldn’t fix it either. Said nothing they could do unless part showed bad. I told them there something I could do Went to the ford dealer traded in. And guess what 80000 miles without one hiccup. This whole deal makes me sick cause I had 1990 Tacoma 4x4 not single problem. Then 2000 tundra SR5 4x4 still have 180000 miles. Starter replaced and that all. Loved Toyota And looks like a $50.00 switch May fixed it.