Reatta Fan Posted May 2, 2003 Share Posted May 2, 2003 All,Thank you all for providing a wealth of technical knowledge and insight into these fine, fun cars. I'm a new owner of a 1990 Buick Reatta Convertible. The oil pressure display is pegged all the way to the max no matter what conditions (hot, cold, revving, idling) except off when it indicates 0. Past posts indicate that the oil pressure sensor is to blame. (I cleaned the plug and wires to it but still the same.) I then exercised the diagnostics program. For BCM data, BD71 (Oil Pressure) fluctuates between 100-206 during idle. BD61 (Engine RPM) indicates 850. The value of BD99 (BCM PRom ID) is 244. I'm now a bit confused as shouldn't the oil pressure display track the fluctuations the diagnostic program indicates as it's operting off the same sensor (maybe)? The max value during idle was 206 which is less than the max value of 255 allowed. I've read on how to replace the oil sensor but do not want to invest the time or money if it isn't the real problem at hand. Link to comment Share on other sites More sharing options...
Rawja Posted May 2, 2003 Share Posted May 2, 2003 Replace the oil pressure sender, it's a common failure on GMs of this vintage, and the symptoms you describe make that the first thing to try. Link to comment Share on other sites More sharing options...
harry yarnell Posted May 2, 2003 Share Posted May 2, 2003 Yup, it's the sensor. Guaranteed. Link to comment Share on other sites More sharing options...
Guest Posted May 2, 2003 Share Posted May 2, 2003 just got my car back from lynch buick here in chicago, they replaced oil sensor, the gage is still showing max. any comments? Link to comment Share on other sites More sharing options...
Guest Greg Ross Posted May 2, 2003 Share Posted May 2, 2003 OOps!The recommends you've received about replacing the Sender could still be correct. I know from experience that there's a specific Oil Pressure Sender PN? (I'm not at Home!)that is needed to communicate (correct Mv range) with the BCM/ ECM. Had a timing chain installed about a year after I bought my '88 and the shop broke the Sender in the process. Yhey took responsibility but coulddn't get the correct PN. Once I located it in a bigger Metro Centre/ installed it was fine. As I recall The incorrect one read 700 + on the CRT Guage Display.Anyone got the '88-89 Oil Pressure Sender P.N. handy? Link to comment Share on other sites More sharing options...
Guest Posted May 3, 2003 Share Posted May 3, 2003 ok so the sender is something else from the sensor? how hard is that to replace? i might try it myself rather than pay 300 bucks for it Link to comment Share on other sites More sharing options...
padgett Posted May 3, 2003 Share Posted May 3, 2003 Picture and part number here. Should be under $35 for Delco part from distributer (not dealer). Screws into top of oil filter housing. Have replaced with nothing more than a pair of small water pump pliers. (Though usually use a oil pressure sender socket and remove the accessory belt first). Need to be careful because is easy to snap the plastic part off. Link to comment Share on other sites More sharing options...
Reatta Fan Posted May 4, 2003 Author Share Posted May 4, 2003 Gentlemen:Thanks for the hints, tips, and part number for the replacement oil pressure sending unit (#3532954). Because of work and time constraints, I have an appointment at an older well-estabished Buick dealer tomorrow. I made sure to quiz the service advisor about their experience with working on these cars. He said he's been with that same dealership for 20 years and yes, they did sell Reattas when new and have worked on them in the past. I first tried a fairly new large Buick dealer closer to my house. The service advisor at that dealership took a cursory look around the car (before I could explain anything to him) and said they perfer to service Buick products and there are plenty of folks that would work on old foreign cars around town. I showed him the big "BUICK" letters across the back taillight section and said he never saw one of these cars and didn't know anything about them but their service department "would be willing to try" to fix the problem. Needless to say, I was kind of hesitant to have them do the work and continued shopping. Yes, I will post the results afterward. Link to comment Share on other sites More sharing options...
padgett Posted May 4, 2003 Share Posted May 4, 2003 Glad you found a Dealer who understands their quirks.Think max on the "guage" for a 90 is 80 psi so no matter what that value is, if over 80 it will show max. This is a common sensor failure Scottzilla: the symptoms you mention (0 when engine off and key on, goes instantly to max when engine starts) could also match having a sensor designed for an idiot light (on/off) rather than a guage. Part number should be stamped on base of unit. Need to look at the diagnostic value to see is just two values or changing. If not 3532954 then I would keep the removed part, and complain to the first dealer, they should rembuse you. OTOH if max always when key on, even with engine off, that is a short somewhere, either in the sender or in the wiring to it. Link to comment Share on other sites More sharing options...
Reatta Fan Posted May 6, 2003 Author Share Posted May 6, 2003 Just to close out this thread ...After the new oil pressure sensor was installed (#3532954), the display now reads more reasonably and does change value depending if the oil is warm or cold and when the car is idling and moving.Thanks! Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now