Spectrum24x

ok, yes i searched and found hundreds of threads skimmed through most of them and they were all about the same and didnt give me the answers im looking for. i finished my drivetrain swap and everything seems to be working except now my gauge is showing 0 oil pressure. My first thought is that the gauge is faulty because it doesnt move at all, i would think that if something went out causing me to lose oil pressure the needle would at least move a little, but it just sits dead. so my question is 3 part:

1. if it is simply showing 0 all the time, should i be worried that i really have 0 oil pressure? i would think if i had 0 oil pressure i would notice pretty quick!
2. is there a way (aside from buying another gauge) to test my oil pressure and see if it actually has any to give me some peace of mind before i go driving
3. when doing the swap the capacitor that mounts on the slave cylinder broke, i called a rotarty shop and they said its nothing urgent the car should still run normal without it it... would lacking this capacitor cause my gauge to show 0?

thank you for all your help!

RotaryRocket88

iTrader: (7)

A lot of people have the condenser missing, including me. The gauge grounds through the oil pressure sender, so check the clip-on connection and wire. Since you were just working in that area, it's bound to be related.

Spectrum24x

hmm so without the capacitor (condenser) my gauge should still work? the wire that appears to be for the sender (below the oil filter and to the left) is connected and seems to be good... do i need to ground the wire that was connected to the condenser maybe?

RotaryRocket88

iTrader: (7)

The Y/R wire on the engine harness splits at some point. One side goes to the sender, and the other side goes to the condenser. It'll work as long as the sender side is connected. The condenser smooths out the signal.

satch

iTrader: (1)

Don't ground that particular wire. The capacitor is grounded but not the wire without the capacitor. You can disconnect the wire to the oil sender and ground it "briefly" w/key to on and the oil pressure gauge needle should rise indicating the gauge is good. Again, the wire to the oil sender is grounded only briefly to test whether the gauge is faulty or not.

Spectrum24x

Ok, so the wire I thought I should be working with wasn't the right one. I took the connector off. Shoved loose wire into it and grounded it, nothing. Then I touched the wire to the sensor and grounded it, nothing... So then I put the wire into the connector, and touched it to the sensor and grounded it... My water temp gauge spiked so clearly I don't know where the wire for the oil pressure sending unit is located...

Spectrum24x

Got it. The sender doesn't have a standard connector on it, found a thread with good pictures, slid the wire on, gauge reads good.. Thanks for all the help

croglesby

I just changed clutch and flywheel. I found that i was grounding out oil gauge. I went to look at the wiring and found I smashed the condenser between trans and engine ( just myself doing it W/O trans jack ) Bummer ! I tried to move everything out of the way.
Any way I cleaned sending unit connection. ungrounded condenser wire and oil pressure gauge droped below zero. Started and it pulled up a little when gas is given. I read 2 other posts that were older and have not come to the conclusion if i fried oil gauge ( it still moves up when grounded and when not it still moves when given gas) It seems the condenser IS necessary to supply the gauge with correct voltage for accurate reading. But yes before the grounding it did not matter if it was grounded or not. Now that it is not there at all (condenser) I have problems. Weird. I dont want to change sending unit just to guess if that was the problem. my book (Haynes) does not give any test for it. anyone have 2 cents?

RotaryRocket88

iTrader: (7)

No, the condenser is not needed for the gauge to function. If you grounded the wire directly to the block, you may well have damaged the gauge. Grounding it with no resistor in-line should peg the needle. If you pick up a few small resistors from Radioshack, etc..., you can see if the needle will move as it is supposed to. From the FSM:

o5rx8mazda

iTrader: (1)

im having a swimilar issue.. the sender unit is the Saucer looking thing under the oil filter right?? it bolts into the block?? if thats it then there is no wire attatched to it.. i tried looking around to find a wire that connects to it but the sender doesnt seem to have a place to connect something to it just a little stubb on the top.

dwb87

iTrader: (22)

My sender unit has nothing attatched to it either... Which wire is supposed to be attatched to the sender unit??

Does anyone have any pics?

HOZZMANRX7

iTrader: (43)

It's a slide-on connector that goes over the little mushroom extension on the topside of the sending unit. White retangular thing.

dwb87

iTrader: (22)

Thanks HOZZ... Your information, and an old thread that Icemark replied to, helped me find this connector.

The wire got lost somewhere in my engine bay while finishing my TII swap a few years ago. I just thought the oil pressure gauge was broken and needed to be replaced. It seems that this wire can easily be lost and forgotten. Like most people have stated in other posts, it does get completely dirty and gunked-up.

88_N/A_GXL

iTrader: (3)

I have a similar issue, my gauge reads about a needle's width above the 0, but when I hold it around 2k rpm it'll read about 30psi, any thoughts?

Which thread had the pictures in it so I can test my gauge as well.

clokker

iTrader: (2)

You need a new sending unit, gauge is fine.

88_N/A_GXL

iTrader: (3)

So I shouldn't be worried about no oil pressure?

RotaryRocket88

iTrader: (7)

Unless you confirm the pressure with a calibrated, mechanical gauge, I wouldn't trust what the stock gauge shows. Old senders do not work like they used to.

88_N/A_GXL

iTrader: (3)

Any gauge and/or method you recommend or know about on how to check?

dwb87

iTrader: (22)

For method -> Bottom of page 2-5 of "Lubrication System" in the FSM. In this link:

Lubrication System