Why is this turbo so anxious??

"Lugging" to me is when you're pulling a hill in too high of a gear. Had an older car that would also start pinging if doing that.

 

Why does this thread remind me of NoOffRoad4Me?

 

I wonder if putting a Scangauge or iDash on it would be the route to go and see if the boost gauge is even relative to any real engine data.

What’s with the insults? Some of you guys sound like you’ve never owned a new car. This isn’t the “good ‘ol’ days” where things were engineered to work, and last. How many old Supra’s are out there blown up?

I took Marty McFly up against my 2025 this morning thanks to your suggestions and for some reason Doc was on my side, couldn’t quite understand how putting 15lbs of boost under 2k rpm made sense. We were going up hill at 1,500 rpm and instead of downshifting, the boost gauge just maxes out.

I didn’t realize this would be so hard to grasp so we might as well have a conference call to cover the rest.

 

Thank you for the data as always. This graph makes sense.

I really don’t think I’m giving it much beans when this happens, we’re taking 10% throttle position. Maybe I’m not giving it enough beans to get the downshift?

To your point about the automatic, are you thinking this is more likely under conditions of let’s say a bad manual driver? I think hurricane made a good point on this too with MT. You may have hit the nail on the head there. Thanks.

 

And that’s exactly my concern. May need to give it a bit more beans to get that downshift I’m expecting.

 

Me too. Too much load at low rpm’s and the engine let you know.

It would rumble, or ping in some cases. The rumble was more common.

 

There’s probably enough computerized management to prevent this, I haven’t noticed knocking under these conditions. Appreciate the data and gear ratios provided.

 

Trucks are heavy, the hybrid even more so.. so yeah if you're in like 7th going down the freeway and you step on it, it's going to spool up a lot to accelerate.

You're never going to lug the automatic.

Put 91 in it and leave it in D. I've put 91 in my truck since the first tank, there is zero reason to not offer your T24A-FTS extra knock protection.

 

I’ve considered 91. My last few vehicles required 93 so not shocked by price increase. Thought I saw the owner manual mention a recommendation for 91 as well.

 

This. /thread

 

Lemme finish ‘Ye…


Above - just about sums up my issue.

/thread

 

Does that say 668 miles? You've got a long road of ownership ahead of you if this is how things are starting out

Instead of trying to convince us there's a problem with your brand new truck (eg, I didn't realize this would be so hard to grasp), maybe you should try convincing the Toyota dealer instead. Make sure to educate them about LSPI too while you're there

 

Sure does! According to the press release, it’s trying to hold the gear instead of downshifting to make the ride more “pleasurable” which is completely opposite of my last vehicle and pretty much anything I’ve driven.

I doubt the dealer will care. The consensus; you can’t lug an automatic and according to Toyota, it likes to hold the gear which apparently goes full boost even at low RPM.

 

Guessing your prior vehicles (a) weren't equipped with a turbo, and (b) made peak torque at a higher RPMs.

And yes, I doubt the dealer will care. Lugging isn't a concern with automatic transmissions, boost isn't bad (more power for same RPM), and being better at holding the gear on a hill is a significant improvement - 3rd gens scream like a banshee as they downshift on an incline since they don't make max torque of 265 ft-lb until 4600 rpm rather than the 4th gen's 317 lb-ft @ 1700 rpm (and 465 lb-ft @ 1700 rpm for the hybrid Tacoma).

 

One exception to the general characteristics seems to show in the tow/haul mode. That might be load dependent too. Our son's keel/cabin style sailboat is not near the full tow capacity, but it's also tall and not aerodynamic. The tow/haul mode limits 8th gear and also seems to drop sustained high boost.

Overall I just don't worry or care too much. My 2024 is a wonderful improvement over past models and alternatives. A whole lot have shipped now. Nothing in official complaints or news shows them to be the trouble some makes and models are.

 

Last 2 vehicles were twin scroll single turbo v6’s. Very new to turbo world. Those allowed you to keep boost down until higher rpm’s with light throttle depression. I’d been accustomed to that for 4 years and this turbo seems a little too anxious, thus the post. Those were max torque at around 1,500rpm but also I always tried not to boost full pressure under low rpm just as a principal. I’ve learned a lot here and thank you again for your help of course!

 

Yes, noticed as well with the modes. I’ve been doing some towing, the engine behaves totally different using tow mode. Keeps rpm’s around 2k and less boost pressure under acceleration. It’s interesting to see the dynamic while towing going between the modes. I do feel like tow/ haul is best for towing.

I love this truck. Glad to hear that previous gen owners are impressed with the improvements, I’m loving it! So far so good, just seemed a little odd how the turbo was behaving, but looks like this is completely normal according to the press release.

 

just curious, with an undersquare motor why do you feel the that’s “low rpm”? I’d also ask what you feel is negative with the turbo spinning up?

for disclosure I don’t presently own a 4th gen, my experience is a few test drives when I thought my 3rd gen might be totaled following an accident. Loved the motor, especially the hybrid. WAY better than 3rd gen IMHO. I plan to move to 4th gen but first want to see 2026 info.

 

Great question. I just learned about undersquare engines last week thanks another member here. Process a little deeper into it, I’m thinking of 6k rpm’s with 2,000rpm being a third of that, so logic being that the engine shouldn’t be pressured to 15psi of boost with 2/3’s to go if that makes sense. Based on that logic, 1/3 = low, 2/3 = med, and 3/3 = high?

I’m imagining a system (the engine) that sucks air in to gain revolutions. At lower (1/3) rpm, it would be a negative to force the full capacity of the turbo pressure into the intake. Basically forcing more air into the system than what the revolutions support while also needing to exhaust that increased air pressure as well being a negative. At 2/3 or more, sure give it all the boost you’ve got.

Trying to think of a good analogy where you don’t want to over pressure something that’s pressurized, right away which isn’t turning fast enough to get rid of the added pressurized air. Need to get those revolutions moving to support that forced air and to exhaust it! Could be hillbilly logic.

I’m hoping the explanation above makes at least a little bit of sense. I feel like I did a terrible job explaining this and got blasted for it.

Basically when under the slightest throttle the turbo gauge goes on full blast made me think “why is this happening?” I could understand if I’m mashing the pedal, but you would think, it would take mashing the pedal to get the full boost pressure.

I’m not getting on it, all I’m trying to do is maintain speed uphill, which seems like I’m always falling behind on the ascent while the turbo and MAX gauge are on full.

It’s almost as if the gauge is fake and designed to make you think “wow it’s getting full boost!! Brappppppapppp” While I’m sitting here going “why so much boost for so little pedal?”