First Issue with the engine T24A-FTS (1 Viewer)

[LCQ]

UPDATE (see post #9: dealer replaced the Duty Vacuum Switching Valve, 90910-12284)

Encountering the first issue with this engine isn't reassuring, but I'm thinking it could be a relatively minor valve. And I'm hoping I've got it pinpointed. It's a chirping cricket noise from what appears to be the Duty Vacuum Switching Valve, 90910-12284 - this part number is stamped on the actual part installed on mine. Interestingly, that part has been superseded by 90910-AC005, but I haven't done much digging into what has changed (if there's any info out there).

I first thought it could be the high pressure fuel pump but I'm not even sure if that's in this area. After some checking with the stethoscope, I'm 85% sure it's coming from this vacuum switching valve.

When does it show up? Mostly after driving a long trail at high elevation, but I think it's correlated to the engine bay being relatively 'hot' or fully warmed up. It's much more prominent after 30 minutes of sub 10mph low range driving climbing a mountain. But I have replicated it with city driving, although it's much less pronounced.

Here's a video of the noise in case others will encounter it. My dealer is booked out for 2 months, so I'll update this once Toyota has had a look at it.

Since I'm a novice on this turbo, is this (the driver side) where the intercooler is stacked with the intake manifold and high pressure fuel pump in close proximity? I'm trying to figure out what else is there that the noise could be channeling from.

 

[OGBeno]

The part supersession indicates (the ACxxx) localization of manufacture for that part for service part support for the US market. 90910-AC005 is also utilized by the Tundra. Ergo, Toyota will substitute the localized part for service part support.

 

[Zill]

That sound is there to remind you that it’s a 4 cylinder squirrel engine instead of the big V8

In all seriousness, that’s not normal and glad to hear the dealership is replacing the part… and it’s easy to access.

 

[carboncycles]

Trying to follow along...so it's a noise that shows up after certain conditions. Is this causing drastic loss in power or negatively impacting the performance? Or is this a hyper sensitivity to problems from the V6TT?

 

[LCQ]

That sound is there to remind you that it’s a 4 cylinder squirrel engine instead of the big V8

In all seriousness, that’s not normal and glad to hear the dealership is replacing the part… and it’s easy to access.

You must be a V8 lurker. I agree it’s not normal. This is a noise far different than the typically referenced diesel sound of the 4 cylinder.

Not so far with deslership, they’ve yet to even have a mechanic diagnose it.

 

[LCQ]

Trying to follow along...so it's a noise that shows up after certain conditions. Is this causing drastic loss in power or negatively impacting the performance? Or is this a hyper sensitivity to problems from the V6TT?

Yes, it shows up after the engine is in the warm/hot side. Pretty sure I never heard it in the first 1,000 miles, despite the same sort of driving then.

There is no noticeable loss of power or performance. Not in the slightest that I can discern. Scanned for codes on my torque app but nothing has showed up. No check engine lights, nada. Just a squeaky noise that is clearly not normal. You can hear the chirping noise from 10 feet away with the hood closed when it’s at its loudest.

You could call it a hyper sensitivity to the TTV6. But I’d argue most of us on mud are hypersensitive to any sign of issue with our Toyotas. With a new platform, first model year, early in the first MY production, I’m paying attention to anything that’s abnormal so Toyota warranty can take care of it.

Machinery sometimes likes to give you some audible warning before it completely fails. This is where I think it’s at. Complete failure could be at 200k but I’d rather get the squeaky wheel greased/replaced before finding out the limit.

 

[Zill]

You must be a V8 lurker. I agree it’s not normal. This is a noise far different than the typically referenced diesel sound of the 4 cylinder.

Not so far with deslership, they’ve yet to even have a mechanic diagnose it.

Both 200 and 250 owner, but I do wish we had the option for a V8 in the new platform.

Sorry I misread that - they’re 2 months out to even look at it? That’s nuts.

Are there any other Toyota dealers reasonably close to you that can take a look?

 

[LCQ]

Both 200 and 250 owner, but I do wish we had the option for a V8 in the new platform.

Sorry I misread that - they’re 2 months out to even look at it? That’s nuts.

Are there any other Toyota dealers reasonably close to you that can take a look?

Yeah it’s a little nuts they are booking that far out. They did say if driveability is affected I might get in sooner. If it gets worse I may go that route.

I’m checking with another dealer an hour away but they haven’t gotten back yet. Beyond that it’s a pain to take it further. Also I’m thinking it’s gonna be one of those, we’ll have the part in 3 days and need you back then to install.

 

[LCQ]

Update: dealer said it was the Duty Vacuum Switching Valve, 90910-12284, I suspected. They installed the new part, 90910-AC005, and the chirping appears to be gone. If anyone else encounters, I think a quick test is to disconnect the plug going into it and see if the noise stops.

Glad it ended up being a minor part replacement. Will update the thread if anything changes.

New part below