Oil pressure gauge

Hi guys.

Suddenly my XLT 92' 4x4 Explorer oil pressure gauge needle goes down from the "m" of the "normal" to "o".
The needle still keeps steady over the "o" but I'm very worried about.
I've check the engine and the oil level is just fine, and no oil pools are in the floor on the parking place.
In fact, just few days ago I change the oil and filter and after that everything goes OK, until today.
Could be the pressure sensor? If the problem is the oil pump, the engine must be removed to change these part?
Somebody knows how to check the oil pressure, and what is the normal oil pressure in the 4.0 L. engine?
Is the oil pressure gauge in the Explorer a "dummy" one?
My Ex has 168.000 miles now.
I don´t want to drive my Ex until found what's goin'on.
Thank in advance
Andy

I believe that the oil gauge is a "dummy gauge" that is, it doesnt do anything unless your oil level is below a certain amount, then it swings all the way to the left. Mine does the same thing where it swings around, but It's prob just due to resistence in the wire as the summer brings warmer temperatures. Do a search for "dummy oil gauge" and youll find all the info you need.

Thanks a lot, jgilbs. I'll do the search right now.

Erratic gauge

jgilbs said:

I believe that the oil gauge is a "dummy gauge" that is, it doesnt do anything unless your oil level is below a certain amount, then it swings all the way to the left. Mine does the same thing where it swings around, but It's prob just due to resistence in the wire as the summer brings warmer temperatures. Do a search for "dummy oil gauge" and youll find all the info you need.

Click to expand...

I just experienced the erratic gauge syndrome. Out of the blue, the oil pressure gauge starts to go from a steady normal reading to a low reading every second or so. This would happen when driving down the road or at idle speed. I fixed this problem by removing the wire connector on the oil pressure switch mounted on the engine and putting it back on. Scientifically, I think this is called the "wiggle wire" trick. The oil pressure gauge is now steady again. The wife feels safer driving the X when all the gauges are "normal".

I've periodically had the same problem. I found that if I bang my fist on the top of the dashboard my oil pressure guage will pop back up to normal. Leads me to believe my problem might be the guage and not the oil pressure sending unit.

Well, indeed the X oil pressure gauge is a dummy one. The Ford dealer mechanic told me that. When the oil pressure in the engine reach a preset level, the gauge goes to normal. If the oil pressure drops under that level, the gauge goes to the red line, That's all, the gauge don't measure or indicate a "real" oil pressure.
I fix the problem by miself. Just disconnect the wire from the oil pressure sensor, give it a shots of WD-40 and that's it. Now work just fine.
Thank to all you folks for the help.

Nice rides!

Andy

Dummy Gauge

Well, I hust had the same problem too! I want to take that wire off and do the wiggle trick as well. I just need to know where the right wire is. I have been also having problems with the temperature gauge. I was going DOWNHILL to Phoenix last week and the temperature gauge went past the "L" in normal. I was way worried so I pulled over and checked everything. No leaks, fan was working. I did go the rest of the way with no A/C but the temperature gauge rested right on the "L" of normal. Note: It was 107 degrees outside. Oh, and the gauge usually sits below the "N" on Normal.

I agree that the gauge is "yes, there's pressure" or "no, there isn't". As long as the oil is normal and up to level, I think it's very unlikely for oil pressure to suddenly drop out. If seriously in doubt about it, the real time pressure can be checked with gauges under the hood.

Flyboyerau:

Unlike the oil pressure gauge, the coolant temp gauge is a "real" gauge, I mean, it reflects the engine coolant temperature. If you get a high reading in a downhill trip, that's bad.
I just guessing, but if you don't have coolant leaks and the level is OK, maybe coud be a stuck thermostat in closed position, wich avoid the coollant flows freely through the engine's cooling system. Also could be an obstructed radiator.
Anyway, at 107 degrees outside is usual that the cooling system don't work so efficiently that at lower ambient temperatures.
Maybe was nothing than a very warm day.

I hope this helps

Andy

I just have and update on my earlier erratic oil pressure gauge problem. At first, I removed and reattached the wire connecting to the oil pressure switch. The problem went away for a few days and then started back up again with the gauge in the dash going erratic again.
I then replaced the oil pressure switch last week and now the gauge is steady again. Others have said that they removed the switch and cleaned all the oil sludge that had built up inside the switch and that solved their problem. But for about $10, I have a new switch installed.
Hope this information helps someone out there with the same problem since this seems like a very popular problem with our X's