emeretta

Finally got to take my new girl on a decent road trip!

So a couple weekends ago, 2000klm since it's last oil change, drove from Hamilton to Orangeville. Crawling through town I noticed when I was sitting at a stop that my oil pressure gauge on the dash wouldn't just stay centre as it always does, but would flicker, never bottoming out, never topping out. As soon as I was off idle it was solid centre again. Drive back from Orangeville to Hamilton did the same thing, and this time I had a passenger to confirm that I wasn't just seeing things. Made a stop for a few minutes, started again, and the problem did not reoccur, even through the engine was just as hot.

Next road trip from Hamilton to Parry Sound did the same thing. I'm about 1000klm from my next oil change, but the level is still okay and the condition is not bad for it's age. And again back to Hamilton it did the same thing.

The other gauges appear fine, the volts are steady, the rpms aren't changing at any noticible rate, no CEL, no other dash lights. "Check gages" doesn't even light up as this is happening. No external oil leaks.

The boyfriend thinks it's just the pressure switch, but I feel it would happen more often if it was, or it would stay steady at high or low depending on what the computer was reading from the sensor. I've read some Fords have issues with the IAC so then I wondered if it was trying to stall and not an oil pressure issue.

Is there anything I can do besides just wait for it to happen more consistantly or (ideally not) wait for it to cut out completely?

I would get it diagnosed at a shop, but it only happens after long trips. And that's hard to mimic in the city.

desertrat

Maybe the gauge is doing what it is supposed to do: When the pressure drops, as when at low idle, the gauge shows it. When revved up it has better pressure. Check to see if it does the same thing when it is cold. Or is it when the oil "thins out"? Possibly nothing wrong, but if it has never done it before it should be looked into.

oldfordman

Not sure about the 03's, but on my 99 the oil pressure gauge is run by an idiot light sensor. The pressure sensor is just a switch that triggers at about 8 psi. There is a resistor on the gauge that makes the gauge show mid-way whenever you have more than 8 psi oil pressure. not one of Ford's better ideas. The oil pressure sensors are notorious for going bad, behave just like you describe. Relatively cheap, but a tight fit to replace (behind the head on the right side of the motor). I would try that first. If it does not fix it, you may have low oil pressure problems that could be anything from a bad oil pump, bad cam position sensor, or worn bearings.
WARNING- The late 90's and up 3.0 engines are noted for having problems with the cam position sensor. It sits on the top of the block, in the rear, just off center to the right side. On older engines it is where the distributor was. The lower part of it engages the gear on the back of the camshaft, and also drives the oil pump. If this fails, the engine will keep running, but you will have no oil pressure and if you don't shut down quickly, you can seize the engine. I have read about these sometimes failing as early as 60K miles. If you are in the back of the engine to replace the pressure sensor, it would be a good idea to check the condition of the cam sensor. Not real difficult, but it needs to be done properly, and aligned, so get a manual or Google for the instructions.