High Oil Pressure
08-07-2019, 01:59 PM
#16
Rennlist Member
I agree with Breakaway, you might try and remove the OPRV, inspect for damage or misalignment and reinstall see if that changes anything.
Probably should use the tool for reinstalling, thou I've done it successfully without.
08-20-2019, 11:08 PM
#17
Hey folks, wanted to close the loop on this.
First, thanks for everyone's help! Kudos to SeanR for mentioning the (at least in the end) correct resolution to this issue.
So here's what happened, in order-ish: ('no improvement means cluster light still on, gauge needle pegged at MAX)
* ME: checked wiring, sensors,
* took it to friendly mechanic (not a Porsche guy) to empty out the oil. He told me that wasn't a problem, and was concerned about the oil light thinking it was low oil (which for the '83 is not the case).
* pressure measured with mechanical gauge, oi was at 5-6 bar
* replaced oil with 0W-40 synthetic, filter, no improvement
* checked sensor, turns out connector was broken before, so replaced that, no improvement
* checked oil pressure relief valve (OPRV) - it was dirty, but otherwise fine, and is the newer generation OPRV, no improvement
* friendly mechanic gave up, and suggested I take it to a good 944 shop beause he was out of ideas
* 944 towed (thank you roadside assistance) to nice 944-expert shop
* new shop (also very friendly) called and said that (after 1.5h of work), polarity was reversed and it was fine now, with 4.8 bar at cold start and 2.5 bar when engine is warm
Here are my takeaways:
1) sensor WAS busted (previous mechanic had installed it and broken one of the contacts), replaced
2) OPRV was (per friendly non-944 mechanic) grungy, but fully functional and of a newer generation; and he did clean it when he took it out
3) polarity was reversed, at least the second time around
Friendly mechanic was not an expert shop and was doing me a favor, so props to him. Also pressure was theoretically high. 944 shop said maybe they weren't familiar with using that mechanical gauge on the 944, and that could be the case too.
First, thanks for everyone's help! Kudos to SeanR for mentioning the (at least in the end) correct resolution to this issue.
So here's what happened, in order-ish: ('no improvement means cluster light still on, gauge needle pegged at MAX)
* ME: checked wiring, sensors,
* took it to friendly mechanic (not a Porsche guy) to empty out the oil. He told me that wasn't a problem, and was concerned about the oil light thinking it was low oil (which for the '83 is not the case).
* pressure measured with mechanical gauge, oi was at 5-6 bar
* replaced oil with 0W-40 synthetic, filter, no improvement
* checked sensor, turns out connector was broken before, so replaced that, no improvement
* checked oil pressure relief valve (OPRV) - it was dirty, but otherwise fine, and is the newer generation OPRV, no improvement
* friendly mechanic gave up, and suggested I take it to a good 944 shop beause he was out of ideas
* 944 towed (thank you roadside assistance) to nice 944-expert shop
* new shop (also very friendly) called and said that (after 1.5h of work), polarity was reversed and it was fine now, with 4.8 bar at cold start and 2.5 bar when engine is warm
Here are my takeaways:
1) sensor WAS busted (previous mechanic had installed it and broken one of the contacts), replaced
2) OPRV was (per friendly non-944 mechanic) grungy, but fully functional and of a newer generation; and he did clean it when he took it out
3) polarity was reversed, at least the second time around
Friendly mechanic was not an expert shop and was doing me a favor, so props to him. Also pressure was theoretically high. 944 shop said maybe they weren't familiar with using that mechanical gauge on the 944, and that could be the case too.
