well seen its a vl it sounds like a common problem, does your car missfire going up hills or at idle or any other time?
as the CAS (crank angle sensor) in vls are renowned for going and cauing types of problems i have discribed, it would be a best bet to have a look in your dissy cap for any signs of orange dust or mosture cauing inproper spark,
orange dust is signs of CAS bearings are stuffed and cauing the dust to spread on the CAS disc making it fire and missfire iregularry
if it gets worse in time to come, i would strongerly recomend checking all your ignition system, plugs, leads or cables connected to the dissy system and also check all you sensor which can cause this and poor fuel econemy,
the temp sensor and o2 sensor are the only real sensors that can cause a prob
hope it helps