I have a 93 twin turbo, automatic transmission. What is proper oil pressure at idle and when running? Should you use 10W30 all year or 20W50? Finally, would using the two different weights impact the oil pressure? Thanks, Mike

 

Oil pressure will vary at idle, senders and/or the single wire connection to the sender can get dirty (right under oil filter pedestal) and give wierd readings. IIRC, when up to temp, mine reads about 15 to 20 psi at idle. The FSM advises that minimum pressure at 3k rpm is 50 psi. And yes, the oil's wieght, engine RPM, engine/oil temp will all play a role in indicated pressure.
Welcome to the forum, but if you search there have been alot of posts on this recently.

 

If you're seeing low oil pressure, it could be a bad/tired sending unit. Give Ray Crowe at Malloy Mazda a call for all your OEM parts, he has the sending unit on sale right now for 75 bucks:

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/oem-part-heaven-2007-ray-crowe-has-gone-crazy-his-prices-617547/

 

^Just ordered up that center console switch panel. Thanks for keeping us posted.