Rear spoiler ram adjustment
 

The rear spoiler on my 2002 car rises and retracts just fine but with one minor fault: the left hand side never retracts fully and needs a push to get it to sit flush. The error is small, only around 1/8" (3.5mm).

I thoroughly examined the obviously accessible parts of the mechanism when I recently replaced the bumper and found I was not rubbing or binding anywhere, but there were witness marks showing that when my bumper got damaged it must have briefly pushed on the left side of the spoiler, and careful measurements showed there's no body distortion. I played around with the small amount of adjustment where the spoiler mounts onto the rams but there was no improvement.

Before I try buying a replacement spoiler ram and drive motor assembly (which is only around £40), I was wondering whether there is any adjustment to the ram travel end points? I'm also unclear as to whether the drive motor drives a cable or operates a hydraulic system: it looks mechanical in the photos I've seen but some vendors describe it as being hydraulic. If it's mechanical then I may be able to strip it down and see whether a drive cog has been knocked out of alignment by a single tooth.

What are all the adjustments for this? Mine is diagonal going into the slot....the rear bumper cover is close to being contacted on one side. There are some bolts on the post ...