Help!! Oil "gauge" reading zero.

[427435]

The vehicle is a 2003 Ford Explorer EB with the 4.6 V8.

I figured it was the sender. I replaced that and checked connections. Still "gauge" reads zero. Removed sender and used air pressure to check the sender (off the vehicle)----sender OK.

What else could the problem be? I've got oil pressure as I driven it 100 miles with the zero reading and it runs fine without any lifter noise etc.

Anyone run into this?

 

[jacobl]

My 02 explorer was doing pretty much the same thing as you describe.
I disconnected the battery for a couple of hours to reset the computer. Reconnected it and the oil pressure gauge is now working normal.

 

[427435]

Thanks for the suggestion. Tried it and at least the gauge goes through a calibration swing when you turn the ignition on the first time, but still no oil pressure reading when the engine is running.

I've ordered a service manual and wiring manual. Plan on running a separate wire from the sender to the gauge once I get the manuals. Also plan on adding a real gauge.

 

[jacobl]

The gauge may be bad. I would drive it with caution. How many miles are on your explorer?

 

[427435]

There's 52,000 miles on it. I was sure it had oil pressure or the lifters would quickly collapse at idle. I added a real gauge today and it's ready over 60 psi.

Once my service manuals show up, I'm going to see if a new lead from the sender to the gauge input will also clear that up. Then I'll have the best of both worlds---a real gauge and a audio/visual low pressure warning.

 

[rrgone]

I think the 'guage' in the Instrument Cluster is really just a fancy idiot light that turns a yes or no signal from the oil pressure switch into an 'indication'. It could be a wiring problem between the switch and IC or maybe the IC itself is bad, but I don't think any of the individual IC components are servicible. You've already done the right thing by adding a real pressure guage.

Where did you order the manuals? I covet a good wiring manual for my '02.

 

[427435]

UPDATE: I got the service and electrical manuals (bought them on ebay) which showed how to take the dash apart (without breaking something). The electrical manual gave me the wire color and connector info to allow me to run a separate wire from the oil pressure sender to the instrument panel. Everything now works as it should. Must have been a break in one of the original wires or a bad connection in one of the 2 connectors between the sender and the panel.

Anyway, I now have the best of both worlds. A real gauge and a warning if the oil pressure drops.

 

[94Matt]

I have been going through the same thing. Replaced sender, checked pressure. Everything appears to be correct. I took it to the dealership and they told me the gauge is bad and needed to be replaced. The test mode sweeps the gauges correctly.

Ill hang on to my $650.00 and try to fix it my self...

Too bad 427435 is not around anymore. I would have loved to see a write up on how he fixed it.

I have to get my car inspected for my registration renewal and they wont pass me with the dummy light on.

 

[427435]

As I posted above, I fixed mine by splicing a separate wire as close to the sending unit as possible. Then I ran it through the firewall (taping it to an existing bundle of wires) and spliced it to the wire feeding the idiot gauge on the back of the instrument panel.

Probably a bad connection somewhere in the original circuit. Running a separate wire was easier than trying to find the bad connection or break in the wiring.

 

[twinkie]

I had the same problem too a couple days ago. I actually thought it was because of the Fram oil filter I was using. I changed the filter and the oil and it still read "zero". Actually mine would bounce from time to time like it was having some kind of power failure. So, I replaced the sender unit and disconnected the battery for a while and now its all working just fine. if it does this again I will just install a real oil pressure guage and be done with the Ford "idiot" version.

 

[94Matt]

As I posted above, I fixed mine by splicing a separate wire as close to the sending unit as possible.

Thanks for the update. I was referencing more to which wires behind the guage you tapped into. I dont have a problem running the wire, Ill have to hit up alldata for the wiring diagram to the light.

 

[94Matt]

I was so sick of seeing my gauge read bad so I decided to tear into the dash today. I used Xtremerangers great walk-through as well as the following guide.

I used a multi meter to check the signal that the white w/red was getting to the gauge. I was getting voltage from the harness to a ground. It looks like either the brand new oil p sender unit was bad or there was an issue with the circuit.

I installed a T tap on to the white w/red and will run a separate wire to the oil sending unit. My truck was still hot after a run to wal-mart for the multimeter so I taped off the connection. It is very tight trying to get to the sensor and I didnt want to burn my hands again. I will splice it into the wire off the sending unit later in the week when I have time.


This is the left side harness that plugs into the IP. There are one on each side.