Oil Pressure fluctuate's - Page 3 - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

Closed Thread
 
 
 
Thread Tools Search this Thread
Old 05-01-2009, 11:00 PM   #21
Member
Posts like a V-Tak
 
Join Date: Feb 2009
Posts: 30
Thanks: 0
Thanked 0 Times in 0 Posts
96Bonne124 is on a distinguished road
Default

Would post what the oil pressures were reading with the mechanical gauge at operating temperature?

Thanks
Jim
96Bonne124 is offline  
Old 05-02-2009, 02:44 AM   #22
Member
Posts like a V-Tak
Thread Starter
 
Join Date: Apr 2009
Location: Tampa, FL.
Posts: 37
Thanks: 0
Thanked 0 Times in 0 Posts
smkr420 is on a distinguished road
Default

Sorry 96 i was not there when he ran the test.. I will shoot him a call 2marro try and find some one that will show me.
smkr420 is offline  
Old 08-13-2009, 09:09 PM   #23
Senior Member
Posts like a 4 Banger
 
Join Date: Sep 2008
Posts: 133
Thanks: 0
Thanked 0 Times in 0 Posts
zecc81 is on a distinguished road
Default

So?!?!? Did replacing the sensor fix it?!?! I have a very similar issue with my car.
zecc81 is offline  
Old 08-17-2009, 11:02 PM   #24
Member
Posts like a V-Tak
 
Join Date: Oct 2007
Location: Arlington, VA
Posts: 63
Thanks: 0
Thanked 0 Times in 0 Posts
Ironduke is on a distinguished road
Default

Quote:
Originally Posted by Thin Indian View Post
Wow. If that was my car and I was having the exact problem with the oil psi, I would have put at least 10w40, probably 20w50, knowing summer is coming.
Was the pressure dropping before you changed the oil?

Maybe you should change it back out, and capture the drained new oil to put back in next November.
I've always run the recommended oil in the summer, something lighter in the winter. e.g. in my 6000 5w30 was recommended, I'd run that in the summer, 0w30 in the winter. On my Bonneville 10w30 is recommended, I'll run 5w30 in the winter. Then again I've lived in areas where it literally got to -50 on the mercury.
Ironduke is offline  
Old 09-28-2009, 05:55 PM   #25
Junior Member
 
Join Date: Sep 2009
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Dyanik683 is on a distinguished road
Default

I just took care of a very similar problem for my brothers engine. Here is what I found to be wrong with his:

A year ago the car was driven for a significant period of time with a failed upper intake gasket, the car eventually hydro locked due to excessive coolant leaking into the intake. I tore it down re-sealed the entire upper end from head gaskets to the throttle body. All was well for about 3 months until the oil pressure started to fluctuate. Cold or above 2k rpm hot it would get to 40psi, hot at idle it would struggle to make 10-20psi.

We tried adding assorted liquid fixes and heavy weight oil with some success. 30 wt and zmax got him limping by until we found a low mileage replacement engine. Still ran fine with maybe a slight lifter tick the day I pulled it. The original had 145k.

After removing the engine I removed the oil pan and found excessive play on two maybe three of the rod bearings, I have no questions that the mixing of the coolant with the oil for however long that gasket had been leaking toasted the bearings. It is very possible that replacing the bearings would have corrected the problem but I found a great 50k used engine trans combo instead.

Best of luck with yours.
Dyanik683 is offline  
Old 09-28-2009, 08:43 PM   #26
Member
Posts like a V-Tak
 
Join Date: Feb 2009
Posts: 30
Thanks: 0
Thanked 0 Times in 0 Posts
96Bonne124 is on a distinguished road
Default

Thank you for your post. Very informative. Do you know if the rod bearings you found loose, whether they could be changed with the engine in the vehicle.

Some individuals I spoke with about my car indicated too much guessing as to where the problem is and would recommend overhaul or new engine. Cost and value of the vehicle becomes the issue. My car really has no ticking noise; once it gets to operating temperature it wants to stall out.

I've contemplated changing the IAC motor. No codes other than security light is on.


My Bonneville, it cranks fine and runs but is presently not reliable.

thanks again
96Bonne124 is offline  
Old 09-28-2009, 09:05 PM   #27
Member
Posts like a V-Tak
 
Join Date: Mar 2007
Location: Mt. Pleasant Mi
Posts: 33
Thanks: 0
Thanked 0 Times in 0 Posts
D. Rustin is on a distinguished road
Default

My '98 just developed the same oil press. problem so I changed the oil level sensor and no change.
I plan on also installiing a mech. gauge and go from there.
D. Rustin is offline  
Old 09-29-2009, 11:42 AM   #28
Junior Member
 
Join Date: Sep 2009
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Dyanik683 is on a distinguished road
Default

The oil pan can be easily removed with the engine in the car, clean working conditions and working on your back may be an issue trying to replace the bearings though. I imagine with the right amount of determination and small fingers it would be possible.

An important note, the Oil level sensor on the front of the pan has clearance issues with the oil sump tube when dropping and installing the pan. Unscrew the sensor and let it set loose through the hole and it will make life much easier. I broke one the first time. through.

The problem with picking and replacing parts is that if one part has excessive wear, it is likely that other parts have excessive wear also. Main bearings, balance shaft bearings, rings, valve guides... it is a game of luck at best. The overall condition and mileage of the car should help decide what to do. If the car is very solid otherwise a rebuild or low mileage salvage may be a reasonable option. If there are other looming issues, Chassis rust, suspension issues, body corrosion, transmission problems, limping by on heavy weight oil and additives may be the way to go while saving for a new vehicle.

To my brother I recommended nursing the old one along and saving for a replacement car. He disagreed as he does not have much money and really likes this car. It has a considerable amount of under body rust but is in excellent shape on top. I've already replaced most of the suspension, portions of the brake and fuel lines, fuel pump, wheel bearings, and brake calipers.

We were fortunate to find a 51,000 mile car fax verified motor and transmission pair for $1000.00 less than an hour away. Finding this was very fortunate as a direct swap needed to be from an H body 96-99 vehicle. There are two possible final drive ratios also further complicating matters, a 2.84 and 3.06. Engines from W body and later model Bonneville'* will work but they require some electronics and parts swaps.
Dyanik683 is offline  
Old 09-30-2009, 09:35 PM   #29
Member
Posts like a V-Tak
 
Join Date: Mar 2007
Location: Mt. Pleasant Mi
Posts: 33
Thanks: 0
Thanked 0 Times in 0 Posts
D. Rustin is on a distinguished road
Default

I installed a mech. gauge today drove it and the oil press only went down to 20 psi at idle when the car was in gear.
Tomorrow I'm going to buy & install a brass tee so I can hook up both gauges to see what the mech. gauge says when the elec. gauge nosedives.
My b-in-law thinks it may be either main bearings or the oil pump.
D. Rustin is offline  
Old 10-01-2009, 08:57 PM   #30
Member
Posts like a V-Tak
 
Join Date: Mar 2007
Location: Mt. Pleasant Mi
Posts: 33
Thanks: 0
Thanked 0 Times in 0 Posts
D. Rustin is on a distinguished road
Default

Okay I installed a brass nipple & brass Tee then installed both the Dash elec. gauge sending unit & the mech. gauge line and fired the car up upon startup the mech. gauge was reading about 20 p.*.i. more than the dash elec. gauge drove it and after it warmed up the dash gauge started dropping into the red almost near zero while the mech gauge never dropped much below 20 p.*.i.

I'm going to call the auto parts store tomorrow just to make sure they sold me the right sending unit for the dash gauge.
So for now it looks like the dash gauge is at fault.
Surely someone else has had the same problem and figured it out.
D. Rustin is offline  
 
 
Closed Thread

Related Topics
Thread Thread Starter Forum Replies Last Post
RPMs fluctuate while driving uphill zjohn647 Oldsmobile 15 04-29-2014 10:34 AM
very high oil pressure reading after oil change txmike 1992-1999 3 01-10-2010 11:41 PM
1995 SE--burning oil, low oil pressure gauge. AeroCoupeSS87 1992-1999 2 12-10-2007 09:52 PM
Low oil pressure. Thicker oil? J Wikoff 1992-1999 71 06-08-2006 11:54 AM
Low oil pressure sensor in oil pan... Bob Dillon 1992-1999 9 05-11-2006 09:23 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 08:08 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.