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Bad engine mount

Car is a 2005 Honda Odyssey, approx. 120K, purchased used with 100K and inspected by an independent mechanic. We are now getting a loud engine noise when the engine is warming up, when accelerating or above 2K on the tach; it largely goes away when the engine is warm and idling, or when the engine is below 2K or in eco mode. It sounds like hole in the exhaust system but the mechanic thinks it may be the engine mount. Any idea if this is a typical symptom of a bad engine mount - I’ve that read increased engine noise is a symptom but usually more a clanging noise.

Thanks.

You can check the engine mounts yourself by “power-braking” the vehicle in both Drive and reverse…Have an observer watch for excessive engine movement while this is done…A broken mount will usually result in dramatic engine movement…

So, pop the hood, drive the cars backwards (at a reasonable speed, not like Steve McQueen), and then jam on the brakes, correct?

No, hold your foot on the brake while revving the engine in reverse, and then in drive.

The problem might just be a matter of the flex pipe of the exhaust system having a separation in it. That situation could be caused by a bad motor mount (which allows too much engine movement), or it could just be the result of 120k miles of usage.

All motors move when tested as @jesmed suggests. You don’t have to apply much gas while you hold the brake. Problem is you might not be able to distinguish normal movement from too much movement.

To your question a broken mount can allow too much engine movement and that can damage the exhaust system especially at the joints and connection points. Where the exhaust pipe connects to the exhaust manifold is one area that can break and you’d hear the noise toward the front of the car in this case.

I think you need to have a mechanic inspect the mounts and exhaust system to locate the problem.

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Thanks for the suggestions and help.

Yeah It does not sound like the mount to me, especially since it goes away at idle. That is usually when you feel it the most. IF your Van has the cylinder deactivation (depends on your trim level, but when you pop the hood if you see VCM on the motor cover you have it), then in “eco” mode it is actually shutting down cyls, and on those vans the motor mounts are “active”. A V6 running on 3-cyls cause a good deal of vibration, so again assuming your van has VCM and since yours is not making noise in “eco” mode it is again pointing to NOT motor mounts.

“Power Brake”…Firmly holding the brake, apply a modest amount of power in drive for a few seconds while someone observes the engine for excessive movement. Anything over one inch is excessive. Repeat in reverse. Do not use more than 1/3 throttle and do not hold power on for long. Just a second or two is enough to make the observations…

What you are doing: You are using engine torque to apply some stress to the motor mounts. A weak or broken mount will allow the engine to shift position, sometimes alarmingly, so be alert to that possibility…