Oil Gauge jumps

[mathedm]

I have a 2002 Ford ranger Edge. When I let off the clutch the oil gauge jumps and makes a clicking noise. Anyone know if this is possible an electrical problem and if so, what do I need to replace first. Thanks for any responses.

 

[ati190]

Oil pressure sending unit. Cheap to replace, however I've never heard of guages clicking, but I imagine it's possible.. The better thing to do is install a mechanical guage. Also, a cheap remedy for this problem, and guaranteed assurance you have pressure. The stock oil guage is USELESS, and unreliable. The OPSU is nothing more than a switch that is set to close at 7-8psi. anything above that is read normal, anything below is read below normal. Furthermore, at 8psi you'd have a dead engine very fast.

 

[mud390]

Is there any way to replace the stock sending unit with one that actually reads the real oil pressure? Maybe from a different model, or even aftermarket? I just got my Ranger a week ago and the oil pressure guage is probably the most annoying thing to me about the whole truck.

Kris

 

[mathedm]

Thanks, I will check into these things. I just wanted to make sure nothing was wrong with the actual oil pressure and I wouldnt be driving down the road and the truck to go dead.

 

[ati190]

It's a possibility, but unlikely. The oil pump either works or it doesn't. Like I said hook a mechanical guage up, and find out. Most likely it's the stock sender that's causing your issue. As for mud's question, i'm unaware of any senders that do those, as they are electrical. (nothing more than a switch). There maybe variable resistor senders out there, but I don't know of any. The mechanical guage is about a 10 minute install, very easy. You can also get a T, so both your dash guage, and the mechanical guage works.

 

[Hawk1339]

Is there any way to replace the stock sending unit with one that actually reads the real oil pressure? Maybe from a different model, or even aftermarket? I just got my Ranger a week ago and the oil pressure guage is probably the most annoying thing to me about the whole truck.

Kris

The stock sending unit can indeed be replaced with a variable sender. A simple procedure, just replace the sender and jumper out a 20Ω resistor in the instrument cluster. I got the sender at NAPA, part number MPEOP6091SB, cost about ten bucks. Of course you still don't get any real numbers with the stock gauge, just the "Normal" range indication, but you can see the behavior of your oil pressure.

Here's a site that details the mod:

OIL PRESSURE SENDER

 

[mud390]

Hawk: Very cool! Thank you! I'm assuming that my 03 would have that same resistor? Also, is it possible to swap out the sending unit from the top side of the motor? How much oil should I expect to see come out of the block when I pull the sending unit?

Kris

 

[Hawk1339]

Hawk: Very cool! Thank you! I'm assuming that my 03 would have that same resistor? Also, is it possible to swap out the sending unit from the top side of the motor? How much oil should I expect to see come out of the block when I pull the sending unit?

Kris

Since I don't have a wiring diagram for an 03, I can't say for certain that the resistor is there, but my hunch is that it is, and works much as described in the article. Maybe someone else can confirm this.

As for the sending unit, my experience is more with 90's era Rangers, but again my hunch is that not much has changed. The sender is most difficult to change on a 3L as it is on the back side of the engine, behind and below the valve cover on the passenger side. It's easiest to get to from underneath or through the wheel well. On the 4 cylinder it's on the top rear side of the block, driver's side, on the 4L it's on the side of the block, driver's side. The sender itself is fairly universal with Fords; the one I'm using (click here) is specified for vehicles dating back to the 60's. I don't think they've ever changed the thread size, the only variations have been with the connector (tab vs. post). The NAPA one was the most inexpensive I could find, get that one and you can't go wrong.

Ordinarily you should have little or no oil come from the sender mounting hole when you remove the sender, assuming you remove it with the engine off, of course. A little residual weep, that's about all. Put a few turns of teflon tape around the threads of the new sender before you install it.

If you can't get to the whole job at once- taking apart the dash to remove the instrument cluster takes some time- you can install the sender, then modify the resistor later. You won't hurt anything electrically, but you will have very low pressure readings until you jumper the resistor. On my 93 there was no shortcut- to get to the resistor I had to completely remove the instrument cluster.

 

[mud390]

Excellent info there! I appreciate all the help! Something to for me to definitely look into when I get some down time.

Kris

 

[PJRNM]

Old thread...still great information. I have the gauge flicker as of today Any picture of the location of the sending unit? I don't want to remove the wrong thing!

 

[Hawk1339]

Old thread...still great information. I have the gauge flicker as of today Any picture of the location of the sending unit? I don't want to remove the wrong thing!

Go back to this page and scroll down, there's a picture of the backside of a 3.0 with the tranny removed. The location of the sender is indicated. Again, it's hard to get to, but not impossible.

 

[PJRNM]

Thanks, I've got one on order...I was hoping it would be the $10 mentioned in a post, unfortunetly it's $30.....Still a cheap fix.

 

[Hawk1339]

Thanks, I've got one on order...I was hoping it would be the $10 mentioned in a post, unfortunetly it's $30.....Still a cheap fix.

For others contemplating this mod, the inexpensive sender from NAPA mentioned previously is still available, as is this example from Advance Auto Parts- part number S334, made by Borg-Warner, for about $12. Since the Ranger never used an actual gauge sender, the trick is to look for one specified for an older Ford vehicle, such as a late 70s or early 80s F150.