I found some issues on my rear air level system that I experimented with that solved my problem.


Jack up the rear on stands.
Remove both rear tires

On both side sensors: the level arms should be 'exercised' to full swing up and down several times, and spray oil into the joint. I confirmed that my level sensor was stuck at 4.4 volts in any position until I disconnected the pillow ball linkage, and operated the level to full swing positive and negative several times. The left side was responding to a level change just not the right. And when I was performing the level calibration procedure, I would call the ECU function to raise the suspension and would be perplexed as to why the airbags would inflate to raise the rear axle and then drop down again. The reasoning is the sensors were not sending accurate feedback voltages from their measurements to the control module.

Perhaps there was dust inside or something. I had this problem on the left side sensor, and then two weeks later on the right side. Which were both solved.

The pillow ball joints need to be spray lubricated, and the linkage needs to be free moving over the balls. Previously mine were corroded and stiff.

The lever arms and the connecting rod must be pushing at the correct angle again once the vehicle is lowered back down.


The calibration procedure was performed using ISTA/D and I can't recall the procedure now but I have it written in my notebook exactly.

Bonus tip: I use the product 'AT-205' in a spray bottle, spray the airbags and I used a gloved hand to get the back side of the airbags. This can prevent cracks. I have cracks in my bags, but I don't have any leaks so I want to keep the rubber from drying out.

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2003 4.6, esotril blue, over 215,000KM. Every previous owner failed to keep up the vehicle maintenance. Restoration project.