Oil Pressure Gauge

[flemm]

Hello All: Little History. Have a 95 Aerostar, 3 litre, approx 199699 kms. I noticed today that my Oil Pressure Gauge arrow is over on the far left bypassing L (Lower). The gauge should read in the normal area. The book states to shut off vehicle and get repairs. Before I go to a garage, can anyone give me a heads up of what could be happening. Something else to state. Before I noticed this, there was yellow on the snow in my driveway. I check the rad and it was empty. I filled the rad back up with premix antifreeze and so far can determine no leak. I dont know whats happen in last 24 hrs to cause this. Any help is appreciate.

Flemm
NOVA SCOTIA

[ken1mod]

It is well known what one of the major causes of Yellow Snow is.

Engine oiling systems are very reliable, your problem is more likely the gauge electrical circuit.

Ken

[JTHill24]

Flemm:

I would replace the Oil Sending Unit on the back of the Engine. Make sure you replace with the right one. They gave me one that was bigger than the one on it and it read Low. Got the Smaller one that was like the one on it and my Oil Pressure went back up to where it should be.

Jay

[96_4wdr]

you along with 99% of other Ford owners have the "Yellow Snow" Ford design cheapy oil "gauge" that is really a dummy gauge with a sender spst switch, you are actually reading the current flow thru a 20 ohm resistor in your dash...can Ford get any CHEAPER

sender wire fell off end of sender switch, switch is plugged

how is the level on engine dipstick, if overfull, you may be measuring more than oil...Ford has had a problem with headgaskets blowing/corroding out, more common on 3.8 and 4L

the "oil sender unit" on the Aero engine is actually a electrical switch that closes at 6 lbs psi completing the circuit with the dash idiot gauge and a 20 ohm resistor on the dash circuit board.....search Aero forum and FTE for other Ford owner upgrades to idiot gauge

I fixed mine on a 4L and now have a REAL oil pressure gauge...

see mod to make it a REAL pressure gauge
common to most Fords of 80's>early 2000's
your mileage may vary depending on engine and switch location

http://rogueperformance.com/oilsw.html

[ken1mod]

Hey 96, since you have a real oil gauge on your 4.0, does it vary much in normal operation.

When I replaced worn rod bearings, I was disappointed to see no difference in oil pressure. Then you guys told me why. What ford does with that gauge is really disgusting. I hope they don't do that sort of thing any more or their stock will drop to 3.00

Ken

[96_4wdr]

gauge goes up to middle when i start it...after engine's hot, it drops to mid left at idle...goes back up to middle when crusin...
i wanted a gauge that read more than 6 lbs psi...

actually, the reason Ford went to the Idiot Gauge was that too many men owners and purchasers of their trucks and cars wanted something more than a red idiot light that turned on below 6 lbs psi, so Ford engineering had a brainfart idea, we'll put in a dummy gauge and make it read high normal all the time, male owners of big masculine trucks were happy, women were happy...no complaints about "My F250 oil gauge reads lower than Joe's down the street"....everyone's oil gauge reads the same...it's a happy face corporate engineered world

rod bearings have to be almost non existent to affect oil pressure, it travels up hole to wrist pin and sprays out to lube/cool piston/cylinder so not much back pressure at rod bearings....

main bearing wear, thrust bearing wear causing leaks and excessive tolerance are usually the culprit in low oil pressure problems

loose rod bearing just sound like hell

their stock keeps dropping because they only make cars that government agencies and rental car companies want anymore

[flemm]

Thanks to all for your input. Is it true that if I did damage to the engine it would not start. The van starts and runs fine. Ford tells me to bring it in. I will but would like to know all possible problems before they take my wallet. They state it could be the sensor or much worse. My limit is 1000 dollar repair or the van is junked. I must say (knock on wood), I have had very few problems with this van since I purchased it. KNOCK KNOCK.

[JTHill24]

Flemm:

Go to the Auto parts store and pickup a Oil Sending Unit ($5-15) dollars.
Replace it yourself. Ford will charge you a couple of Hundred Dollars to do the same thing. If it don't fix the problem you can always take it in. No need to pay them
$30-$50 dollars for the same part.

Real easy to change. Pull the cover from inside the van and it's right there on the back of the engine.

Jay