Excessive Valve Train Noise ('00 GTS 19k miles)

[siwell]

I took my car into the dealer to fix the belt/tensioner sqeal issue and came out with an excessive valve train noise issue. The dealer is contacting Toyota Technical on Monday for more information.

The dealer asked if I had mis-shifted (the old 6-2) and I'm not sure that I have. I'm a fan of engine braking and this is definitely related... so, I have a few questions:

a) What is the proper use of engine braking?

b) What are acceptable tolerances for this engine?

c) What sort of repairs should I expect from the dealer?

[LaW]

wait, the old 6-2??? ok whatever that's not the most common misshift but oh well its 3-2 man :) oh yeah no one cares wait i'm being ghey

[siwell]

6-2 or 3-2, it's irrelevant. What's your idea of a 3-2? I'm talking about coming from a straight into a tight corner while engine braking. That didn't answer any of the previous questions.

In general, how does engine braking impact the wear and tear on the engine (no matter the gear)?

[LaW]

hey brakes are cheaper use them :) I just know that the cost of whatever wears is a factor and brakes are cheaper :)

oh yeah if your on a straight most people have been shifting to 4th and hitting 2nd....

[ishido]

a) What is the proper use of engine braking?

Emergency situations perhaps. The engine is not made to brake. The only times I've heard of engine braking being crucial is on long downhill runs where brake fade may occur and you may not be able to stop. It can also seriously upset the weight balance of your car if you're going into a turn or are on some slippery conditions. Basically... you shouldn't do it except to avoid brake fade-which our car doesn't have (see Motortrend Dec 01)

[siwell]

So engine braking is bad and brakes are cheaper than new engines... are we in agreement?

Any other opinions on engine braking?

I like to rev down in 3rd and 2nd when coming off highway ramps. I do this by double clutching but I know it's not necessary to use the engine at all. It usually makes up for the decline.

[QWKsilvr808]

I've hear discussions on this topic several times before. Some ppl argue that downshifting or "engine braking" is better because it saves wear and tear on the brakes. Sure it saves the brakes, but it puts wear on your clutch, motor mounts, and drivetrain that wouldn't have to happen if you just tapped the brake pedal. The brakes are easy to replace, and not all that expensive really in comparison to the extra wear and tear of your other driveline components. Especially at the higher speeds you must be coming from off of the highway.

Like ishido said, you should use engine braking on steep declines to assist your brakes, but there's rarely a real need for it other than that. I only use this technique if I'm going a little TOO damned fast and need to help my brakes out a little. Otherwise I pop it into neutral and just use the brakes. :)

[ishido]

Double clutching or rev matching as you downshift would be fine. Letting the engine wind down naturally... but going thru all those shifts is more of a pain than simply using your brakes.

The idea behind rev matching is to put your engine in optimal range to take off, say... out of a corner. So you aren't dogged down in a higher gear.

I got out of the habit of engine braking when i bought a motorcycle. At least w/ a motorcycle, the engine kills itself if you downshift too many gears :) And if you engine brake on a bike, the rear is a LOT more likely to get loose and be upset.