Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Technical BBS > 1- Porsche Technical Forums > Porsche 928 Technical Forum

Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered User
 
Join Date: Jun 2015
Posts: 12
oil level light

There have been a couple of threads on this topic in the past, but none seemed to come to a resolution, so I'm going to post this problem I'm having --

I have a 1982 928S (has spoilers so I think that makes it an S), which I bought a few years ago and been driving only periodically as I am trying to restore it into working order (timing belt project, CV joints, A/C conversion to R134a, climate control problems, etc).

my current issue is the Central Warning Light and oil LEVEL light come on periodically, typically when the engine is under load (during acceleration up an incline especially, but also occurs when level). My oil pressure is steady 4-5 bar, oil pressure light does not activate. No lifter noises from engine.

Of course I have changed the oil, replaced with a new filter, 20/50W oil. my level is up to the highest mark on dipstick. I check all the wires leading to the oil pressure sending unit (replace the connectors which were corroded) checked the wire leading to oil level sender unit (perfect condition) and even removed the oil level sender unit to verify that it works.

I've looked at all my grounds and 14 pin connectors, cant seem to find any significant corrosion.

I'm really at a loss here and wondering if its just a Central Warning System gremlin or if there really could be an oil system issue (like oil not returning to the pan quickly enough?!). My oil pressure seems strong, so I'm feeling like I'm safe to drive, but obviously a bit concerned about that as well.

Hoping for some ideas! Thanks!
Old 09-11-2017, 06:19 PM
  Pelican Parts Technical Article Directory    Reply With Quote #1 (permalink)
Registered User
 
stepson's Avatar
 
Join Date: Mar 2010
Location: Texas
Posts: 1,421
It is a known problem for oil to pack into the heads of the 928 engines at higher RPMS. Is that when you are experiencing the warning?
__________________
John Curry (Drift King) 928OC member
Grand Prix White 1994 GTS AT (The GTS)
Cobalt Blue 1989 S4 AT (The Blue Car)
Indishrot 1984 Euro S AT (The Stepson)
Black Metallic 1984 Euro S 5 speed (The Schwartz)
Old 09-11-2017, 07:22 PM
  Pelican Parts Technical Article Directory    Reply With Quote #2 (permalink)
Registered User
 
harborman's Avatar
 
Join Date: Dec 2009
Location: SW MIchigan
Posts: 1,976
Garage
Is 20W50 oil recommended by Porsche? I use to put that in my Harley.
__________________
1986 928S
32 valve engine
All stock, automatic, 539 Weissgold Metallic, 70K original miles, Hankook Ventus 2 tires.
Previously owned: 67 Vette, 427 L88 Stingray, 74 De Tomaso Pantera L
Old 09-12-2017, 04:47 AM
  Pelican Parts Technical Article Directory    Reply With Quote #3 (permalink)
Registered User
 
stepson's Avatar
 
Join Date: Mar 2010
Location: Texas
Posts: 1,421
Quote:
Originally Posted by harborman View Post
Is 20W50 oil recommended by Porsche? I use to put that in my Harley.
20w50 is what we use down here in God's country. I'm not sure where the OP is, but if he's in a southern clime, that is what he should use.
__________________
John Curry (Drift King) 928OC member
Grand Prix White 1994 GTS AT (The GTS)
Cobalt Blue 1989 S4 AT (The Blue Car)
Indishrot 1984 Euro S AT (The Stepson)
Black Metallic 1984 Euro S 5 speed (The Schwartz)
Old 09-12-2017, 09:06 AM
  Pelican Parts Technical Article Directory    Reply With Quote #4 (permalink)
Registered User
 
Join Date: Jun 2015
Posts: 12
western Pennsylvania, but summer driving...20/50 is listed as optimal. this occurs around 3000 rpm so not really pushing it
Old 09-12-2017, 07:10 PM
  Pelican Parts Technical Article Directory    Reply With Quote #5 (permalink)
Registered User
 
stepson's Avatar
 
Join Date: Mar 2010
Location: Texas
Posts: 1,421
How does your engine harness look? Are there places of corrosion especially around the 14 pin connector? It could be merely an intermittent short in a bad part of the harness.
__________________
John Curry (Drift King) 928OC member
Grand Prix White 1994 GTS AT (The GTS)
Cobalt Blue 1989 S4 AT (The Blue Car)
Indishrot 1984 Euro S AT (The Stepson)
Black Metallic 1984 Euro S 5 speed (The Schwartz)
Old 09-13-2017, 09:07 AM
  Pelican Parts Technical Article Directory    Reply With Quote #6 (permalink)
 
Now Available for Ordering:   101 Projects For Your BMW 3 Series 1982-2000  [more info]
Registered User
 
Join Date: Jun 2015
Posts: 12
14 pin connector looks good but I cleaned it with some electrical cleaner and an airhose to be sure (see photo).

the 20/50W oil is recommended (see photo from my manual). in fact, i did have 10/40w in the engine initially and still had the same problem.

you mention that oil tends to pack in to the heads, but i just cant believe that 2+ quarts of oil could(i figure that the oil level would have to be about 2 quarts down for the switch to activate, given that there's 1.5 quarts between hash marks on the dipstick). I even decided to try adding an extra 1/2 quart overfill but this still occurs.

some one suggested to me that if I remove the wire from the sending unit, and the problem goes away, then it the sending unit is faulty. In fact, i did remove the wire and the problem went away, suggesting its not an electrical issue. However, I removed the entire oil level sending unit, but it seems to be working well, suggesting that the oil sump is dry!

I'd hate to remove and rebuild the heads/engine but i'm thinking that there is something wrong in my oil system internally like a plugged oil channel

heres some photos:



Old 09-13-2017, 01:57 PM
  Pelican Parts Technical Article Directory    Reply With Quote #7 (permalink)
Registered User
 
stepson's Avatar
 
Join Date: Mar 2010
Location: Texas
Posts: 1,421
If you removed the sensor from the circuit and the light did not reoccur, then it would stand that the sensor is faulty.

I've never heard of an oil level sensor going bad, but there's always a first time. Call 928 Intl for a used replacement part. IIRC, 928 Intl offers a year warranty on their used parts.
__________________
John Curry (Drift King) 928OC member
Grand Prix White 1994 GTS AT (The GTS)
Cobalt Blue 1989 S4 AT (The Blue Car)
Indishrot 1984 Euro S AT (The Stepson)
Black Metallic 1984 Euro S 5 speed (The Schwartz)
Old 09-13-2017, 02:35 PM
  Pelican Parts Technical Article Directory    Reply With Quote #8 (permalink)
Registered User
 
Join Date: Apr 2007
Location: SoCal
Posts: 1,672
Garage
Sounds like a gremlin rather than an actual oil level / flow issue.

Grounding the sensor to see what the dash does, as suggested above, seems like the next step.
__________________
1974 911 w/ 3.2 (ugly but kinda fast)
1967 912 (in for, well, everything)
1984 928s (yeah, I really did buy a non running 928)
Old 09-15-2017, 04:58 AM
  Pelican Parts Technical Article Directory    Reply With Quote #9 (permalink)
Registered User
 
harborman's Avatar
 
Join Date: Dec 2009
Location: SW MIchigan
Posts: 1,976
Garage
Put a mechanical gauge on it for a test.
__________________
1986 928S
32 valve engine
All stock, automatic, 539 Weissgold Metallic, 70K original miles, Hankook Ventus 2 tires.
Previously owned: 67 Vette, 427 L88 Stingray, 74 De Tomaso Pantera L
Old 09-15-2017, 05:22 AM
  Pelican Parts Technical Article Directory    Reply With Quote #10 (permalink)
Registered User
 
Join Date: Jun 2015
Posts: 12
Not sure what is meant by "mechanical gauge"...When I ground the wire leading to sender unit, the light on dash and central warning light comes on with engine running...when I remove the wire and drive the vehicle there is no alarm/light. This seems to all point to a bad level sender unit. However, when I removed the sender unit and tested with multimeter, it seemed to adequately close the circuit when I moved the float. Maybe the float or calibration is bad. I guess my only choice is to change the sender unit.

From everyone's responses ( and advice from my dad), if there's adequate oil on the dipstick and oil pressure good, then unlikely to be an oil system problem.

I'll replace the sender unit and update you all. Thanks for the input!
Old 09-15-2017, 05:41 PM
  Pelican Parts Technical Article Directory    Reply With Quote #11 (permalink)
Registered User
 
Join Date: Apr 2007
Location: SoCal
Posts: 1,672
Garage
Keep us posted, and be gentle with her until you know for sure the sender is the issue.

Fingers crossed!
__________________
1974 911 w/ 3.2 (ugly but kinda fast)
1967 912 (in for, well, everything)
1984 928s (yeah, I really did buy a non running 928)
Old 09-15-2017, 06:39 PM
  Pelican Parts Technical Article Directory    Reply With Quote #12 (permalink)
 
Now available:  101 Projects for Your Porsche Boxster!
Registered User
 
harborman's Avatar
 
Join Date: Dec 2009
Location: SW MIchigan
Posts: 1,976
Garage
Quote:
Originally Posted by 928JimL View Post
Not sure what is meant by "mechanical gauge"...When I ground the wire leading to sender unit, the light on dash and central warning light comes on with engine running...when I remove the wire and drive the vehicle there is no alarm/light. This seems to all point to a bad level sender unit. However, when I removed the sender unit and tested with multimeter, it seemed to adequately close the circuit when I moved the float. Maybe the float or calibration is bad. I guess my only choice is to change the sender unit.

From everyone's responses ( and advice from my dad), if there's adequate oil on the dipstick and oil pressure good, then unlikely to be an oil system problem.

I'll replace the sender unit and update you all. Thanks for the input!
A mechanical oil gauge is one that has a small oil line going into the gauge, does not use a sender and is not electrically operated. There are plenty of them on Ebay.
__________________
1986 928S
32 valve engine
All stock, automatic, 539 Weissgold Metallic, 70K original miles, Hankook Ventus 2 tires.
Previously owned: 67 Vette, 427 L88 Stingray, 74 De Tomaso Pantera L
Old 09-16-2017, 05:03 AM
  Pelican Parts Technical Article Directory    Reply With Quote #13 (permalink)
Registered User
 
stepson's Avatar
 
Join Date: Mar 2010
Location: Texas
Posts: 1,421
Harborman,

It's the oil level gauge on the oil pan that he's having trouble with, not the oil pressure gauge.
__________________
John Curry (Drift King) 928OC member
Grand Prix White 1994 GTS AT (The GTS)
Cobalt Blue 1989 S4 AT (The Blue Car)
Indishrot 1984 Euro S AT (The Stepson)
Black Metallic 1984 Euro S 5 speed (The Schwartz)
Old 09-16-2017, 11:21 PM
  Pelican Parts Technical Article Directory    Reply With Quote #14 (permalink)
Registered User
 
harborman's Avatar
 
Join Date: Dec 2009
Location: SW MIchigan
Posts: 1,976
Garage
Quote:
Originally Posted by stepson View Post
Harborman,

It's the oil level gauge on the oil pan that he's having trouble with, not the oil pressure gauge.
OK, I thought he was having pressure issues.
__________________
1986 928S
32 valve engine
All stock, automatic, 539 Weissgold Metallic, 70K original miles, Hankook Ventus 2 tires.
Previously owned: 67 Vette, 427 L88 Stingray, 74 De Tomaso Pantera L
Old 09-17-2017, 04:52 AM
  Pelican Parts Technical Article Directory    Reply With Quote #15 (permalink)
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 


All times are GMT -8. The time now is 09:47 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2016 Pelican Parts - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.