Help! 06 Tundra died at full throttle 70mph?????

[jsncal]

06 v8 4wd Access Tundra:

So, I was driving with Cruise Control on at 70mph, started up a grade and it kicked down hard like it tends to do and then all of a sudden I was losing speed. I turned off the cruise control and pushed the gas to the floor but it did nothing. It just died, I coasted to the side of the road. All the guages and electronics were still on and working. I popped the hood, looked fine. Fired her back up and everything seemed to run fine. No engine light or anything. So the next few days it happens again on the same hill. So I started trying to replicate the problem. It seems when I'm going up a steep grade at highway speeds and it gets close to 5k rpm it sometimes loses throttle. If I keep the gas down it will die, however if I lift off the gas it will kick back in around 2k rpm and I can drive normal again. Any ideas?


I've been reading through posts for awhile and the things that I came up were TPS, throttle body, fuel filter. Sounds like TPS usually throws a code, so throttle body or fuel filter.......do either of these sound like likely candidates? Hoping it's not the fuel filter as it's inside the tank.

Thanks

[DanoDavis]

Hoping it's not the fuel filter as it's inside the tank.

You sure you're not thinking of the fuel pump?

I don't think they changed the location of the filter on the gen-1's.. Should be right up on the frame rail, near the front seats.

[SuckersWalk]

wow. 5K rpm.

[kerryman71]

^^ I was thinking the same thing. Wow!

John

[jsncal]

Yeah, it might have done it at 4500rpm.....the cruise control is scary on the steep grades. It kicks down to 4th then 3rd and usually overshoots the cruise control setpoint by a few mph. It's violent enough that I don't use the cruise when it's wet out. So then later, I was in 3rd at 65mph trying to make it happen again.

[SuckersWalk]

your not driving a C7 vette so what do you really expect to happen with your driving style on a X% grade in a heavy ass truck?

[jsncal]

your not driving a C7 vette so what do you really expect to happen with your driving style on a X% grade in a heavy ass truck?

Driving style? Cruise Control on at 70mph up a long grade.....and the truck dies!!! It's dangerous and not how the Tundra is supposed to operate. There is definitely a problem with the vehicle.

[kerryman71]

Is the cruise control set when it spikes up to 4500 RPM's or are you doing that? I've never had my cruise control get the RPM's up to that much, and I use it all the time. What do you figure the grade to be about? I know you say steep, but what do you consider to be steep?

I've gone up some hills on the highway both with and without cruise control on and have probably never gotten it above 2500 RPM's.

John

[kerryman71]

Another suggestion, check for any stored codes. If you don't have a diagnostic code reader Auto Zone or a place like that will check it for free and give you any codes that may be in there.

John

[SuckersWalk]

Driving style? Cruise Control on at 70mph up a long grade.....and the truck dies!!! It's dangerous and not how the Tundra is supposed to operate. There is definitely a problem with the vehicle.

you said it died once and hasn't done it again. or has it? didn't it die AFTER you disengaged cruise AND then floored it? how much power do you think is available in your heavy ass tundra going up a long steep grade with the engine spinning at 5K rpms? just how do you think the tundra is suppose to operate under those conditions?

[gbeltran]

That sounds like some kind of rev limiter. How much of a grade are we talking about? Mine will only downshift to second if the hill is pretty steep, happens sooner with my boat in tow. I try to turn the cruise off before it happens but sometimes I don't get it in time.

[jsncal]

It has happened a number of times now. The grade is maybe 10-15% but long. The Cruise control in this vehicle at times will downshift and accelerate in a rather aggressive manner when going up hill. This is something I found many people complaining about on various message boards, so I don't believe it is a problem specific to my truck. When using cruise control the vehicle downshifts harshly and then recently at high rpms loses all power. This happens with zero driver intervention, past setting the cruise and is leading to either pulling over stalled on the side of the road until I restart the vehicle, or if I don't touch anything it will give me power again after 5-10 seconds by which time I'm going 40mph. Are people really suggesting that this is normal???? Ridiculous. It certainly is not, and has never happened before, although the downshifting with cruise control has always been harsh. Once this started happening I then tryed to reproduce the problem, which I successfully did by going uphill and flooring it up to 4.5-5k rpm . This is not normal driving practice, believe me I would prefer to keep my rpms low and truck acting normally, but if I have to bring it in to the dealership, better to know how to reproduce the problem instead of spending the money for them to try to make it happen.

[jsncal]

Also, I checked and there are no stored codes.

[Remmy700P]

There's not a damn thing wrong with your truck. It is your driving -- and performance expectations of your vehicle -- that's the problem.

Clearly you are unaware that engaging the "cruise control" on long, steep, inclines (both up and down; and a 10-15% grade is steep) is completely inappropriate. It's a quick way to burn out your transmission, torque converter, etc. They are designed for convenience on flat, open, unobstructed highways only.

Heavy shifting and gear-hunting problems while the cruise control is set are going to be even more symptomatic in the 5-speed A750X-series transmission in the 2005-2006 1-Gens in the conditions you are putting your vehicle in.

Slow down to about 60-64mph on steep grades as that is the optimal "sweet spot" for performance and mileage. And, your transmission won't spend all it's time bucking -- and failing -- your insistent demand that your big-ass truck maintain a low-profile sports-car momentum on these hill climbs.

[CoachRon]

I've never heard of it happening like that before, but I have heard of no throttle response. Usually if one of the two sensors on your throttle body go out, it'll throw a code and you'll get a check engine light. It usually just happens under normal driving conditions too, around 2k rpms. It usually won't give you a response until you shut the truck off and restart it. I've experienced that and I'm thinking that's not your problem. (about $440 if you supply the parts and have the dealer replace both sensors)
I know about cruise control going crazy. If my truck is going up a hill, it'll drop a gear and the rpms will jump up past 3k. I usually cancel it and use my foot if I'm going up a hill, just for that reason.
I'm just guessing, but I would say it has something to do with your rev limiter. Floor it on level ground and see if you get the same results. If the high rpms are what is killing it, and not the hill itself, I would lean towards something like that being your problem.