Engine vibration when idling at red lights

Hi All,

I've been noticing whenever my truck stop and waiting at red lights, after about 10-15 seconds of waiting, I feel slight vibration from the engine. It happens at the same when the "press brake harder to have engine shut off" message shows up on the dash. This vibration occurs even if I disable the engine shut-off with the botton, so it's probably not related to the engine shut-off feature.

This event happens about 70% of the times at red lights. Sometimes it's very light vibration, sometimes it's more pronounced. Definitely not smooth.

This vibration/shudder almost feels like some sort of "cylinder deactivation" when truck is idling at the red light, to save gas (as Hemi does) , but I understand that Tundra doesn't have such feature...

Does anyone notice this on their trucks?
Any ideas?

 

I've searched this forum for keywords and found this one exactly the same description of my issue.

Anyone else noticed this?

 

I don't know if it really happened at the track, but my husband noticed it right away.

 

Just a guess, but it could be a normal cleaning cycle for these engine. This truck has port and direct injectors. Direct for higher efficiency, and port to ensure the intake doesn't gum up with oil. Maybe its just switching between the two at idle

 

I believe my truck does this as well. I just thought it was a less than perfectly smooth idle, but maybe @TopTierToyo is onto something.

 

This is exactly what I have noticed. If you are outside the truck when it shifts from port to direct at idle it even sounds different. I think TopTierToyo nailed it.

 

Mine does the same thing. Very slight however enough to notice it.

 

I experience the same symptom, I’m curious about the injector theory

 

Same here.. sometimes idle surges a bit too. I thought it was my JB4 and took it off but it still did it.

 

This V6TT doesn't idle smoothly in my truck I can feel the vibrations from my seat and steering wheel I wonder if it's due to the longer stroke or maybe because of the Atkinson cycle reducing the compression charge in some cylinders while others are firing maybe this could throw off the crank harmonics?

Edit: When I put it in neutral the vibrations go away completely maybe it's dragging the torque converter in drive at a red light?

I have heard good things about the JB4, does it let you play with any boost limiters or boost by gear logic? thx

 

it does let you do boost by gear but I havent played with those features yet.

 

Looks like you grabbed the wrong quote.
Here is the quote that think you meant to get:
I've noticed when I come to a stop, the engine will idle very low like 350 - 400rpm for a couple seconds then climbs back to normal. But when it does this, I notice a slight motor vibration and the DC power dips down enough to hear the vented seats slow down a bit. Its just like an older car with a bad voltage regulator or failing alternator. Anyone else notice this? Maybe its a quirk maybe I have a problem...

 

I can relate to this. When using the ventilated seats in eco mode and coming to a stop you can hear the motor spool down as if the voltage was being reduced. Maybe it's eco mode messing with it I'll try normal mode today.

 

Noticed the same issue from time to time. It's not consistent. Thought it was the AC compressor cycling on/off, but the engine should compensate for that.

 

I haven’t noticed however I haven’t paid attention to that. You may have a valid point and I’ll be checking out the idle more carefully and report back.