Originally Posted by
pizzaguy
Replace the car's battery.
If that does not do it, we can go from there. I know this sounds like a waste of money, but fact is, most of the time, a funky spoiler is a sign of a weak battery. You can spend time and money on a lot of ideas, but the smartest one is the battery first, then go from there.
(This assumes your battery cables/terminals are not all corroded and filthy, if that is the case, clean things up first.)
I do not think that replace the battery should be the answer, how many people have purchased an unneeded battery? Easy to say but $100 plus is a bit much for some to waste. Jumping from a good battery should be a good test and then a check of the charging system.
In this case I do not know what it could be, obviously a speed sensor signal initiates the spoiler and likewise the retraction, bad switch contact on motor to retract, probably not.