TD5 Back end drops - only when I sit on it!

My first post - probably in the wrong section so apologies.
When I sit on the rear bumper (I am a wasted 15.5st lardy) the back end drops. When I start the engine she raises to the correct height. My worry is, I bought the car to tow a boat and presume that when I hook up, the nose weight will cause the back to drop (when engine off) and the compressor will be running all the time when driving.
Am I correct in thinking I have a dodgy valve in the compressor?
Air suspension seems fine - no sagging, drooping etc.
Any advice greatly appreciated.
Thanks in advance.

I had this problem, check the ride hieght sensors to see if they need replacing and the air springs,
I changed the lot, seems fine now

Thanks.
I bought the car in February and see a new height sensor had been fitted before Christmas. Is it likely that both will need replacing or can you just "give them a wipe" or something?

I would replace both, but its possible that you have leak in an air spring, rub soapy water over them, looking for bubbles.
There easy to replace

I had the same - it was a hairline crack in the top platic of the airbag

OK guys. Thanks for the input. New air springs and sensors it is!!

sounds like you have a leaky air bag.Try spraying soapy water around the airbag to see if there is any bubbles.A tip for you if your td5 is pre facelift.The air filter for the compressor is located behind the n/s/r light cluster and is at the same height as the drain pipe for the rear sunroof because of this the filter can draw wtaer in and ruin your compressor (as it did to mine ). I modified mine by cutting the neck off a 500ml coke bottle and placing the bottom part of the bottle over the air filter housing effectively giving the filter greater protection against water ingress.The later td5's have alonger "mushroom " cover over the filter and don't suffer the same problem.

Thanks for the help. Unfortunately I can't do anymore work on the car now until August when I get back home. Will certainly try your recommendations.

waterboatman said:

My first post - probably in the wrong section so apologies.
When I sit on the rear bumper (I am a wasted 15.5st lardy) the back end drops. When I start the engine she raises to the correct height. My worry is, I bought the car to tow a boat and presume that when I hook up, the nose weight will cause the back to drop (when engine off) and the compressor will be running all the time when driving.

Click to expand...

How much does it drop? If only an inch or two that's exactly what it's designed to do - you're compressing the springs. As long as it lifts itself when you start the engine (with doors closed) and doesn't drop overnight it's fine.

When we hook the caravan onto ours (around 100Kg noseweight it drops quite significantly but soon comes back to normal ride height. And it doesn't drop any more when I stop (except the normal little bit when I get out).