I have an 89 5.0 Mustang automatic, on my way home from work today my oil pressure gauge fell to zero. I changed the oil pressure sending unit and the pressure gauge went to about 30 psi at idle and dont rise much when I take off maybe 35psi. before the old sensor went bad it was reading about 50 psi. The sensor that I was given at the auto parts store dont look like the sensor that I removed from the car i dont know if that makes a difference or not.
That may be about right.....or it may not. Factory readings are inaccurate to say the least. The only real way to find out for sure is to put an aftermarket one on, at least to just check the pressure. On a lot of Ford vehicles, the gauge was wired up with an idiot light sender, meaning that if you had 70 PSI, the gauge would read about in the middle or if you had 10 PSI, it would read right in the middle. Deceitful? You bet.
Neither number sounds right. The actual pressure will vary quite a bit, depending on mileage, temperature, and oil viscosity (weight). Generally speaking, it should be fairly high when cold. Drop a little when it warms up while driving as the oil warms up. But drop considerably from the cold reading when hot at idle. That's normal. If your gauge doesn't do that, then it's inaccurate. The new sender can look differant than the old one and still be the correct one. Aftermarket companies don't always make parts to look like the original. But if the can is considerably smaller than what you took off, you may have a sender for an idiot light.
If the original were linear resistive and the replacement the idiot switch, the OP gauge should have pegged.
Bigred should ground the sender lead and see what the gauge says.
"bigred21001" wrote in news: snipped-for-privacy@u72g2000cwu.googlegroups.com:
Don't rule out the gauge itself.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.