My 85 GSLSE had it's oil pressure indication go to zero on the way home. Since the engine temp did not increase at all, I chanced driving it home and made it. I checked the wiring to the oil pressure sending unit and noticed that the wire to what used to be the condenser was not connected.( I mistakenly trashed the condenser when I replaced the engine) When I grounded that wire the meter indicated full scale. I assume that meant that there was no resistance therefore the sending unit is bad. I have not put a local pressure guage on it yet. Is the condenser just to help cut down noise? What could I do to replace it? Can I use any kind of capacitor? Any ideas on where to get a new or used sending unit at a reasonable price? By the way when driving home, I did consider pulling over and having it towed. However, I had just read an article in the Racing Beat catalog that said that one third of the engine cooling came from the oil cooler. Since the total cooling never changed, I continued driving. Any help would be appreciated.

 

when you unplug the pressure gauge it should max out not when you ground it. But a temp gage will max out when grounded. So if the gage is good the sending unit is bad. Thats probably what it is because if the sending unit went and caused a ground well no reading.

 

I'd recommend avioding the whole thing and drop $150 to get oil pressure, oil temp, and the RB adapter plate. Or just drop $50 to get a new pressure gauge and find somewhere to put the sender. That way you're sure something is or isn't wrong and there's no guesswork.

I know on the 2nd gens the oil pressure gauges/senders are notorious for being shitty. I don't know about the 84-85 13B's but replacing it with aftermarket was the only sure cure.

 

I just had 15 of the oil pressure/temp. blocks made if you want to purchase one. They look a little nicer than the RB unit, comes with the longer studs and o-rings. Mine is anodized black, I am selling them for $35.00. I just called the machine shop and I should have them by Tues. or Wed. I can email a pic once I have one in my hand. PM me if you are interested.

 

Wish I knew you were doing that a couple of weeks ago. Oh well, now when guys look at my engine bay and see the shiny block thing under the filter and ask what it is I can say something like "That my oil injection cross-over unit. It kicks on above 6k to keep the injectors cooler as they approach max-duty cycle. Your car doesn't need it because it's not rotary." Or some other bullshit like that. I love exploiting the world's ignorance of rotaries