QuestionThis is the opposite of most postings as my oil pressure drops to zero (0) when I accelerate. It goes back to 40psi at idle and stops. I replaced the oil pressure sending unit and had the oil changed twice in the past 3 weeks, as my mechanic thinks sludge has built up in the pan.
My mechanic is trying an oil additive and recommended some highway miles to purge the sludge with the next oil change rather than pull than pan. I normally drive 5-6 mile one way to work each day with the occasional longer trip 60-100mi road trip.
Any thoughts?
AnswerLloyd,
Normally, I try the least intrusive methods for repairing issues myself, but this is one problem that I wouldn't attempt this. The absolute first thing that needs to happen is installing a mechanical oil pressure gauge, and recreating the symptoms. If there is still a drop, then I would pull the pan to inspect, and probably replace, the oil pump and pickup assembly. Sometimes, if the pan is sludged, it's possible to clear it by cleaning it out, and either changing the pickup tube, or cleaning it out. NEVER would I add a chemical to do a job that should be done, and examined, by hand. Although I would agree that the entire engine needs to be de-sludged (if sludge is actually the issue), you should not prolong the oil pump cavitation. If the mechanical gauge confirms this problem, then your bearings are not getting lubrication, and this should, in no way, continue.
If the mechanical gauge reads fine, then the issue is electrical -- not likely, but I've seen it before, and this requires a completely different diagnostic.
Good luck!
