Low Oil Pressure S4??
#31
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Iceman,
You can use a cable tie to keep the flaps open. Have you had Devek check your pressure with a guage? If it was my car, I don't think I would drive 140mph with questionable oil pressure. I don't think the flaps closing would contribute to oil pressure drops as severe as yours. FYI, my '89 runs about 2.5 bar at idle with the motor hot using mobil 1 15-50. At the very least, change the oil filter and the sending unit( you need to remove the filter to changes the sender anyway). If you have the filter out, cut it open and look for any "pieces" or sludge.
Good luck,
Jim R.
You can use a cable tie to keep the flaps open. Have you had Devek check your pressure with a guage? If it was my car, I don't think I would drive 140mph with questionable oil pressure. I don't think the flaps closing would contribute to oil pressure drops as severe as yours. FYI, my '89 runs about 2.5 bar at idle with the motor hot using mobil 1 15-50. At the very least, change the oil filter and the sending unit( you need to remove the filter to changes the sender anyway). If you have the filter out, cut it open and look for any "pieces" or sludge.
Good luck,
Jim R.
#32
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Burning or leaking oil has little to do with oil pressure. Synthetic oil does not get as thin with heat as conventional oil. Unless you put the oil in the engine you are relying on hearsay . And YES you might have an internal serious engine problem. Now is the time to find out !
#33
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Originally Posted by heinrich
OK you have just posted the answer, and 2 pieces of information that would have helped a lot to start
. Here they are:
1) ...flaps will close on their own...... temp was climbing ........I opened them and turned the car off....waited .... 5 minutes & started it again ...and it did the low pressure warning.
2) Hasn't done it since.
There's your problem. You overheated the car by hi-revving with closed flaps, then turned it off. At this point nothing can cool your engine because no fans are running. Your oil was boiling.
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1) ...flaps will close on their own...... temp was climbing ........I opened them and turned the car off....waited .... 5 minutes & started it again ...and it did the low pressure warning.
2) Hasn't done it since.
There's your problem. You overheated the car by hi-revving with closed flaps, then turned it off. At this point nothing can cool your engine because no fans are running. Your oil was boiling.
In an engine with a pressurized coolant system, the 'mean' temp will stay at ~ 110C until all the coolant is boiled away: Although the pressurized oil system is a cooling system as well as a lubricating system, the oil will not " boil" as long as there is antifreeze/coolant left circulating in the block.
If the block became hot enough to boil oil, there would be a pretty impressive smoke screen thrown up from melting hoses, seals, etc.
So, hypothetically, oil could boil - cause a pump to cavitate - lose pressure, and so on; however, for that to happen, the block would literally be smoking hot, and the coolant would be upchucked everywhere, and long gone .... that would be approaching "boat anchor" time for the engine.
Back to the problem, certainly agree that a reliable pressure gauge should be screwed on to this engine, and change transducer wires/change transducer as has been suggested: As for the flaps, tie-wrap them open!
#34
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Challenge. Anyone who wants.... go run your Porsche HARD. HARD I mean. Make the temp run up as was explained here, flaps closed, high revs. Now stop and turn her off. At this point call Mark Anderson and order a new engine :-)
#35
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<<Challenge. Anyone who wants.... go run your Porsche HARD. HARD I mean. Make the temp run up as was explained here, flaps closed, high revs. Now stop and turn her off. At this point call Mark Anderson and order a new engine :-)>>
Okay I think I need to clairfy here.....yes I ran the car hard to 140 mph for a few seconds...was only running full throttle for maybe 30 seconds (as we all know it doesn't take long to reach high speeds :>) I drive home for about 10-15 minutes at 70mph...by now the flaps were closed & the temp was SLOWLY climbing....but it never got much over 1/2...never reached the second white line (never ever has since I've owned it).....so the car did have time to cool off.....I would not turn the car off after a high RPM run right away!
The oil pressure was fine at idle right before, & as soon as the RPMs went up it the light went out....
I will remove the flaps & will check/replace the sending unit at the next oil change!
Okay I think I need to clairfy here.....yes I ran the car hard to 140 mph for a few seconds...was only running full throttle for maybe 30 seconds (as we all know it doesn't take long to reach high speeds :>) I drive home for about 10-15 minutes at 70mph...by now the flaps were closed & the temp was SLOWLY climbing....but it never got much over 1/2...never reached the second white line (never ever has since I've owned it).....so the car did have time to cool off.....I would not turn the car off after a high RPM run right away!
The oil pressure was fine at idle right before, & as soon as the RPMs went up it the light went out....
I will remove the flaps & will check/replace the sending unit at the next oil change!