Will failing to replace the oil filler cap after adding oil cause a loss of oil pressure?
Jan 8, 2006 at 1:23 PM
Loss of oil pressure
KELLY71159
- MEMBER
- 5 POSTS
What to check next
Diagnostic guidance. Suggested checks and possible repairs are separate from the owner's reported results.
Have the warning investigated, including actual oil-pressure measurement using the engine's specifications. If the warning returns, stop safely and shut the engine off rather than continuing to drive.
Guidance references and applicability
Source: This question and its visible discussion. Owner reports are distinguished from other participants' experiences. Follow-up guidance is not a confirmed diagnosis.
the FILL cap? no not unless its a sealed system. I don't know of any production cars that use a sealed syst. but replace it just the same, you don't whant dirt getting into the engine. how many miles what engine and what wieght oil did you use?
Jan 8, 2006 at 3:30 PM
After checking the oil and finding it a 1/2 quart low I added about a pint of 10-30 and a pint of additive (you know the thick stuff)
I then drove about 3/4 of a mile to a store without a problem..On the way home I noticed the engine dogging down pretty good and then a few moments later the oil light came on..Right away I realized that I forgot to put the filler cap back on and I stopped to put it back on..The light stayed on for a bit then went off..The engine also began running fine..I drove it to work today without any apparent problems..I'm thinking it was either the cap or maybe the additive clogging something up for a bit..Correct? The car is an 88 Mazada 626..What do think about any potential damage? Should I get the additive back out and clean the screen? Thanks much for your help..
I then drove about 3/4 of a mile to a store without a problem..On the way home I noticed the engine dogging down pretty good and then a few moments later the oil light came on..Right away I realized that I forgot to put the filler cap back on and I stopped to put it back on..The light stayed on for a bit then went off..The engine also began running fine..I drove it to work today without any apparent problems..I'm thinking it was either the cap or maybe the additive clogging something up for a bit..Correct? The car is an 88 Mazada 626..What do think about any potential damage? Should I get the additive back out and clean the screen? Thanks much for your help..
Jan 9, 2006 at 5:51 PM
Oh yeah, the motor has approx. 154,000......
Jan 9, 2006 at 5:53 PM
ummmmm....I guess the obvious question is, when your oil light came on and you realized the filler cap was missing....did you check the oil level again?
Jan 9, 2006 at 10:01 PM
Yes I checked it right away and it was fine..No oil on the engine either...
Jan 10, 2006 at 4:28 PM
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Discussion summary
Loss of oil pressure
After adding oil and a thick additive to a 1988 Mazda 626, the owner drove with the filler cap off, experienced reduced power and saw the oil warning light. The light later went out, and the owner reported normal operation and oil level.
Reported outcome: The owner reported that the warning cleared, but no pressure test or damage assessment was documented.
Neither the missing cap nor the additive was established as the cause. Apparent normal running afterward does not prove that pressure was adequate or that no damage occurred.