Random height issues.

2004 td5 auto with air suspension. The rear left some times works and other times doesn't. If I lift the car fully its fine and stays up but then when I drive or lower it the left drops. I've cleans the ride height sensors. Checked for leaks but can't understand why it's so random? Could it be the cold here -19

99.9% it's the air bag. They have a habit of re-sealing themselves. How old are they? Usually start to give trouble 5 yrs+
Griff

^^^^ As above, first stop is change BOTH air bags. They should be considered a service item with a max 5 year life span. They’re not that expensive and lets face it, they’re rubber bags full of air, if you had a 5 year old tyre that kept going down then you’d replace it, wouldn’t you?

Once you’ve done that then check/replace the ride height sensors, again, not expensive and easy to change.

The odds are by now the fault will be fixed. if not, find someone on here with a diagnostic unit (nanocom, Hawkeye etc) to check for fault codes.

+1 ^^^^

It is often recommended that the battery is disconnected before you disconnect either ride height sensor. There have been cases of the SLABS ECU "forgetting" the height sensor data if the battery isn't disconnected.
I don't know whether it's actually true or not, but it's better to be safe than sorry. If the SLABS has lost the data then you will need a compatible code reader to reset the heights.

Now it's the right side. Doesn't seem to be a pattern. No error on the dashboard. If I raise the car then while driving it settles sometimes the light comes on saying up down problem

If you put it in Off Road Mode (ORM) you gain about 2” in the back however when you hit about 30mph, it will automatically return to standard height. The dash light will flash to inform you it is doing this.
Also when you take the key out of the ignition, the rear is designed to settle an inch or so too.

Don’t worry about left or right at the moment. Assuming no parts have been replaced in the last 5 years;
Think of it as “there is a problem that appears random.
First step, replace air bags.
Second step replace ride height sensors”

Once you have eliminated those (by replacement with new, good quality items), Then it’s worth looking at each side separately. Then start looking at individual connectors/wires/pipes etc however replacing the bags and sensors will 99% chance, fix your problem.

Height sensor was the problem. Thanks

Glad you're sorted