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Eric, Automotive Repair Shop Manager
Category: Car
Satisfied Customers: 30845
Experience:  Automotive Repair Shop Manager, Technician/JA Mentor
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1999 Mazda Miata: mx5..oil gauge..When I disconnect the wire

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I have a 1999 Mazda Miata, MX5. I changed the oil sending unit but the needle in the oil gauge does not move up. When I disconnect the wire to the oil sending unit, the needle does go up to mid point. Do I need to replace the oil pump? I can only find oil pumps for up to 1997 Mazda Miata. What's with that? Do only the dealers carry it?



Does the engine have a rattle or knock, either at idle or on acceleration?


Customer: replied 7 years ago.
knock at idle



Ok, with a knock I do suspect a faulty oil pump as well, but I would advise to rent an oil pressure gauge to hook up in the oil pressure sending unit to verify that there is no oil pressure before replacing it. I do believe in verifying a faulty part before replacing it.


Here is part and link to site you can order it from:,4117&groupid=2459&subgroupid=2486&make=22&model=Miata&year=1999&catalogid=2&displayCatalogid=0



Customer: replied 7 years ago.
Would the local Mazda dealer carry the oil pump?



They should, but if they dont have it in stock, they can order it and usually get it in 3-5 days. Dealership parts departments have a limited space for stocking, and usually cut off at 10yrs on parts they carry in stock on any given day.

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