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CRV grinding noise under hood

Hi Everyone,

Please help! My 2000 CRV (approx 120,000 miles) has recently started making a new grinding noise. I’m having a hard time replicating the noise. It seems worse as the car gets hotter, it’s under the hood, and it will stop for a few seconds if I turn off the AC only to start again on it’s own accord. It will grind away if I am in the drive gear, or if I am idling in park. My transmission also seems to be slipping a bit- it isn’t shifting as well as it used to when going up hills. I’m not sure if that is related or not. Please advise!!!

A possibility regarding that noise is that the A/C compressor clutch is beginning to fail. It is also possible that this is only a loose heat shield. Your engine has heat shields on the exhaust manifold and other parts of the exhaust system, and a loose heat shield can produce a sound similar to a grinding noise.

As to the transmission, this leads to the inevitable question about the maintenance that this vehicle has gotten. Has the trans fluid (and filter) been changed every 30k miles? If not, then your odometer mileage is in the category where you would be likely to experience transmission failure. When transmissions are not serviced every 30k miles, trans failure can take place any time after around 90k miles.

However, it is also possible that the “slipping/not-shifting properly” problem is in reality a problem with the engine’s performance. Many people misinterpret acceleration problems as transmission problems when they are actually engine problems. Again, that leads to questions about maintenance. When was the fuel filter last changed? How about the spark plugs and the air filter?

As a side note, I hope that you have already had the engine’s timing belt changed. A 9 year old Honda with 120k on the odometer is seriously overdue for this maintenance procedure on the basis of both elapsed time and odometer mileage. When a Honda timing belt breaks (without warning), it causes ~$2,000 worth of internal engine damage that can be avoided by changing the belt.

Please report back to us on the various maintenance items that I mentioned so that we can have a better idea of where these problems originate.

Earlier this year, at approx 105,000 miles I had my timing belt changed, along with trans flush, fuel filter, cooling system flush, and diff fluid. I am due to have my plugs and air filter changed soon. As far as having the trans fluid/filter changed every 30000, it hasn’t happened. I think it’s happened 3 times in my car’s life (so approx every 40,000 miles). Would a failing transmission make a grinding noise?

No, a failing automatic trans should not make a grinding sound.
However, a failing A/C compressor clutch could.
And, without being able to hear the sound myself, I do think that you might just be hearing the sound of a loose heat shield.