high idle when starting my 2024 Tundra

Hello to all,

When I start my Tundra in the am or after long periods of not running, it seems that the idle is really high. If I do not wait until the idle goes down, placing in reverse kind of "jolts the truck".

Are there options to lower the idle, or is this just part of the process of warming up the truck?

Thank you,
tstex

 

Mine does that too, I believe it's a Toyota thing. Mine idles down pretty quickly so I just wait to move it till it does.

 

THank you. How long does it take to for te idle to drop? I'll post mine too. thanks again.

 

I'm pretty sure this is an emissions thing to get the cats warmed up as quick as possible. Not just a toyota thing as my Volvo, Chevy, Mazda all do it.

 

Maybe 10-15 seconds, I'll pay attention next time I start it.

 

100% normal and as @DRP mentioned, it is to warm the cats in order to reduce emissions.

And no you can't lower the idle.

 

Thanks to all.

It sounds like I'll start the truck immediately, then do some other things until the high idle ceases....appreciate the feedback

 

Mine has a really loud exhaust note for the first ten seconds or so. I like it

 

An "automatic choke" and "high idle" when starting a car are typically normal behaviors, as the choke mechanism restricts air intake to enrich the fuel mixture, allowing the engine to start easily in cold conditions, and the high idle helps the engine reach operating temperature quickly before settling to a normal idle speed;this is a standard function in older cars with carburetors, and modern cars use electronic systems to achieve the same effect.

 

As others have stated, on a normal cold start I'll give it about 10 to 15 seconds, tops, before going into gear. Still likes to "lunge" a little bit every so often. Want to have the foot well planted on the brake pedal.
On a couple recent really cold days at work, like highs in the single digits, it would go to a REALLY fast idle, almost 2K rpm, before quickly dropping down to it's "normal" fast idle.

 

Thanks B&B

 

Correct me if i'm wrong. But I thought the higher rpm and noise upon cold starting was due to the truck using direct injection to warm the vehicle up, which is louder due to to the direct injectors pulsating under high fuel pressure. Once it warms up a little or you shift into gear the system switches to port fuel injection which is quieter.

 

Some what of a rabbit hole but best explication I can find.

when starting a cold engine, a Toyota D4S system utilizes both port and direct injection simultaneously to optimize combustion and reduce emissions, with the system strategically timing the activation of each injector to create a stratified air-fuel mixture near the spark plug for efficient ignition;essentially, it uses port injection during the initial cold start phase to help warm up the engine, then transitions to using more direct injection as the engine reaches operating temperature.
Also if you youtube car care nut
Why Do Modern Cars Use Direct Fuel Injection? Fuel Injection Series Part 2 at20.20 min and
Toyota's New Engine Technical review Part 1 : Cooling,Lubrication,Direct Injection and EGR at 14.42 min. he tries to explain it.

 

It's kinda funny how complicated they've made it.

Back in the day of carburetors, a choke valve restricted air and opened the throttle plates slightly. The resulting rich mixture allowed better cold starts, better cold combustion, a faster idle RPM, and a quicker warmup period.

I often miss the simplicity of those days.

 

Exactly. I am very surprised the great Sudobash did not deliver a thesis on this subject....

When you cold start the engine it is operating on DFI and a specific cycle (Atkinson or Otto) , after about 30 seconds it switches over to port fuel Injection and the idle lowers as well as the engine seeming to smooth out. This I s when you would place It in R, or D to begin driving.

 

How are these types of questions still being asked in modern times? High idle on cold startup has been a thing on every vehicle for about the past 40 years.

 

It's actually been closer to 100 years.

 

Still very much alive in good, real Japanese motorbikes. Will give you everything you ask of them. EFI: will you give everything its allowed to give you.

 

I can assure you, the idle on my truck is off the charts compared to my last 2-3 trucks/cars. This is why I'm inquiring to both the peak of thd initial idle and the duration. It just seems WAY HIGHER than anything else I've ever had previously.

 

How high are you talking? What rpm when you first start?
Also, the clutch fan always kicks in at first for a few seconds then calms down as well. That could make it sound higher than it is. Every vehicle I've ever owned has done this.

 

Thanks Raven; Ill Ck the rpm's

 

I use those 10-15 seconds to put on seat belt, hit the cancel auto start button, mirror adjustment, put on gloves, turn on heated seats, get tunes or podcast sorted, etc.

 

Driving gloves you say?

 

No heated wheel ?

 

no it’s just cold as hell in the mornings, it that wouldn’t be so bad, sounds like something to ask for Christmas

No sir, SR5 reporting for duty, sir!