engine noise - quick rattle at stops - Toyota Nation Forum : Toyota Car and Truck Forums

johnoh · 05-06-2009, 07:11 AM

My 2004 S-model runs great and has a new air filter, belt tensioner, belt, water pump and cleaned maf/TB/IAC. It used to shake a little in drive when at a stoplight but the TB cleaning fixed that.

When I come off the highway and come to a stop somewhere, it makes a 1/2 second rattle in the engine area, I think on the drivers side. Its wierd that it happens at that first stop coming off the highway.

It happens exactly this way: you are going 60mph, slowing down on an exit ramp, you brake and are slowing down to 30, then 20, then 10 (its silent all this time) and then just as you hit 0, you get a 1/2 second rattle. Not as its stopping, after it stops. Any advice is appreciated

johnoh · 05-06-2009, 12:40 PM

here is some further information. This sound happens exactly when the rpms drop to their minimum, which according to my scanguage is 600. Idling at a stop light is 650-700 rpm and the car is silent. But when having just stopped, the rpms will drop very quickly to 600 before settling on 700.

holler1 · 05-06-2009, 06:58 PM

Might possibly be engine knock from standard gasoline. Try some higher test.

mikered30 · 05-06-2009, 08:52 PM

When you cleaned the TB, did you clean the IACV?

johnoh · 05-07-2009, 07:19 AM

Quote:

Originally Posted by mikered30

When you cleaned the TB, did you clean the IACV?

yes. The car idles at 650rpm normally but at that first stop coming off the highway it gets down to 600. I think that is the problem. Maybe it is starved for air or gas for 1/2 second?

shadowtag88 · 05-12-2009, 02:39 PM

stick or automatic?

could it be as simple as a heatshield... or an auto tranny downshifting thereby shaking the crap around it. ie a heatshield............

atifkm · 05-12-2009, 06:23 PM

this is normal with most of the older models. i also observe this, normally it happens after a big long drive.

shadowtag88 · 05-12-2009, 06:30 PM

eh idk if i'd call it normal. on a 100% maintained car. not that im saying people dont maintain their car.
i mean if it was new, it wouldn't be normal.

perhaps all older cars usually just have a loose heat shield? or just the same problem in general.

johnoh · 05-14-2009, 01:53 PM

Turns out the sound is the hood. The low rpms cause a slight shake of the car, and then the hood rattles. I have not found a way to quiet it yet though - adjusting the rubber stops to make them longer and cause a tighter "fit" when the hood is closed, actually made it worse. Still working on it.........