98-02 Accord Coupe 2.0 Engine Rattle, Noise

[Teamrmaccordcoupe]

There's a rattle when I rev the engine or I turn on my a/c. Any ideas?

[hughezee]

Does the A.C work OK and is it a metallic rattle and have you had the system r e-gassed recently or is it due a top up, basically if your engine is labouring from the load of the A.C this will likely transmit vibration through a worn engine mount or anything loose attached to the engine e.g heat shield on your manifold or catalytic converter?

[Teamrmaccordcoupe]

Works perfectly fine just rattles when I turn it on 

[hughezee]

Something must be loose in vicinity of the engine Rabby

Basically when the engine is loaded by the air conditioning in operation, thus causing a vibration which manifests as an annoying rattle? Personally I cannot imagine its directly related to something loose with the A.C system itself, unless the condenser fan is catching on something,as that noise would come and go

[Teamrmaccordcoupe]

Cheers Stu . Will look into it. One thing after the other right now 

[Laird_Scooby]

I'd look at the cat heat shield to start with and any other heat shields on the exhaust - like Stu says the extra load on the engine can set up vibrations which travel here, there and everywhere, the first thing to rattle will be the loose item and almost certainly unrelated to the air-con. If it is a loose heat shield on the exhaust you could probably find it by grabbing the back box and shaking it.

[Mazda Man]

I had a vibration once...seem to remember it being the heat shield on the manifold rattling.