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Im replacing the plug for my OPSU. Long story short, I need help. I know the cars harness colors and function. Not sure about hooking it up to new plug. Black, Grey and blue. I will try connecting it all and turning key on (fuel pump fuse out) while I wait for guidance.
Something seems not right. Im trying to make sure the new OPSU is functioning properly before I put it back together.
Key on,NEW OPSU un plugged, voltmeter on cars OPSU harness, ground (black) and 5v ref (grey). Looks good. Same as above but probe is on the cars signal wire, yellow/beige. Looks good. NEW OPSU pluged in, ground and 5v ref. Looks good New OPSU pluged in, key on, gague in car goes to 80, and this is the signal reading.
It seems like everythimg is right until I plug the sensor in and it tells the car its high
I recently replaced my OPS plug and the wire colors did not match the OEM colors so I had to pay attention to the OEM wire color and pin position and the new plugs wire color and connect accordingly. If you did that the readings are saying the OPS is no good. So if you verify that the OEM wire color is getting connected to the proper pin on the OPS that would confirm the OPS is no good.
New OPS same results. Pegs to 80 psi as soon as I plug it in.
Your wiring has to be wrong or shorted, mine was shorted and it read 80lbs. After I tugged on the wires it broke at the short and went to 0lbs. Did you verify that it's wired properly.
Figured out the wiring. Does not seem logical. So it must make sense because I suck at electrical. Gauge works! I installed a remote kit. The OPSU seems to long and does not seat all the way down on the extension thus a little weeping. Ill deal with it tomorrow.
the new plug has black, Grey and blue
Black to grey 5v ref, Grey to black ground, blue to white/tan signal.
Figured out the wiring. Does not seem logical. So it must make sense because I suck at electrical. Gauge works! I installed a remote kit. The OPSU seems to long and does not seat all the way down on the extension thus a little weeping. Ill deal with it tomorrow.
the new plug has black, Grey and blue
Black to grey 5v ref, Grey to black ground, blue to white/tan signal.
I'm guessing the crush washer doesn't touch the fitting and make a seal. I found that out myself 2 weeks ago when I did mine. I have a new sensor for a 3.8 that's NPT thread and some new fittings. I'm going to redo it and mount it nicely. I'll post it after I'm finished.
I'm glad mine is not leaking. The thread tape is sealing it. Not correct.
I'm guessing the crush washer doesn't touch the fitting and make a seal. I found that out myself 2 weeks ago when I did mine. I have a new sensor for a 3.8 that's NPT thread and some new fittings. I'm going to redo it and mount it nicely. I'll post it after I'm finished.
I'm glad mine is not leaking. The thread tape is sealing it. Not correct.
You are exactly right, the fitting seems too shallow. Where were you able to find the new fitting? I just got home from work and will try tomorrow to figure it out. I hope to find the parts local. I want to drive her!
I was disappointed when I had the intake off and found the sensor bottoms out in the fitting before sealing. I Teflon taped the threads and tightened the aluminum sensor into the aluminum fitting as tight as I thought I could before stripping the threads and it's not leaking yet. I went with what was suggested on this forum, and I've seen the same parts sold as kits on ebay, Amazon, and some Corvette parts vendors. I don't like it.
I believe oil pressure sensor 12677837 for a 3.8L V6 will work, and I have a new one I will try this weekend. I like it because it's 1/4" national pipe thread and this will solve the sealing issue of the stock sensor to the fitting. I have an -4an to 1/4npt adapter on order now, it should be here Sunday. I will update how it turns out.
Seems ridiculous that the description says use your stock OPS, but that is clearly not the case. I would suggest starting a new thread with your photos and experiences. This is good information as this is a popular relocator kit. Thank you!
Today was a success. Everything works as it should. I'm going to start a new thread later.
I would like to do a 16mm x 1.5 to 1/4npt adapter, have a 16" hose made (turbo oil feed) 1/4npt male on one end for the adapter and female on the other for the Buick 3.8 oil pressure sensor on the other end. Done.
Use the "better" brass Buick sensor and get rid of all of the adapters (and that universal brake hose). Also prefer the npt threads over the 16mm with the crush washer that doesn't crush in that adapter. I mounted it all up with a neoprene jacketed tubing clamp and a m6 x 1.0 stainless nut.
Thats fantastic! Yesterday I took the intake off and removed the remote kit, put in the new sensor and put it all back together. Works for the first time since i bought the car. I will assemble a relocator like yours and remove the intake for the last time. This will be a great thread! Thank you!
Oil Pressure Sending Unit problems
