Hi,

Looking for help diagnosing a problem with my 2003 Accord. Manual transmission. When I accelerate beyond 2500rpm with the A/C on i get a horrible whining noise. I can feel the vibration in the shifter and if it happens when I'm driving I can notice the car jolt a bit. When i turn the A/C off the noise and other symptoms do not occur. I just brought the vehicle in for a A/C service. They recharged the system. It seems to have made the problem intermittent but still it occurs when the A/C engages and the rad fans come on. I think it's intermittent because with a fully charged A/C the compressor switches off more frequently. It's like clockwork.

Any suggestions. Anyone have a tech bulletin on this?

Thanks for your help.

Cheers,
Jeff.

 

Just to add to this. The jolt in the car only occurs when I'm above 2500rpm and the A/C engages while I'm driving.

 

If they had to add a lot of R134a to the system, then there must be a leak somewhere. Adding dye to the system will help locate the leak.

A leak will not cause a whining noise. A noise like that would point a problem with the belt tension, a bad compressor pulley bearing, the clutch gap being off where it slips, a problem with the magnetic clutch.

I would start with the simple stuff first. Inspect the inside of the serpentine belt for cracks or any damage. There is a ground on the compressor magnet that you might want to clean with some sandpaper then re-tighten.

Also, you could hook up a test light by back-probing the power connector for the compressor and see if you are losing power when you get that jolt.

 

V-6 or 4-cyl?

Mine (4-cyl) had a spring-loaded belt tensioner with a mark to show when its travel is outside of acceptable range. That means replace the belt because it's stretched too much.

But the belt can also get hard & slippery from age, even without stretching. Water or belt dressing on the belt will quiet it down for a while - that'll tell you if it's the belt squeaking.

Finally, look for ANY pulleys that have bad bearings that are squealing. Tensioner pulley, waterpump, anything. Just because the AC engages, that puts more load on the belt & possibly makes a marginal bearing get noisy.

 

make sure that system is not overcharged