Driving to work this morning, I noticed my oil pressure guage was going from normal, to absolutely no pressure..

I have another 800 miles to go before my next oil change..


What could be the problem?

 

Well, just to be sure, check the oil level. The best way to find the problem is to install an oil pressure gauge instead of the factory gauge. If infact there is low or no oil pressure, this gauge will be much more accurate. Hopefully your factory gauge is just pooped out. If you have an ear for engine noise, you can tell if there's pressure or not. I wouldn't drive it unless you know it's getting oil one way or the other.

 

Oh, and HEY!! Welome to !!

 

80% of the time it is the sending unit, but verify as 7700 said.

 

I concur with the previous recommendation to put a direct pressure gauge to see what the actual pressure is.]

Did you notice any noises when it went to zero? If not probably just sending unit.

I will give you a case history on a 93 Ford with a V6. The guy who owned it came to me with the following symptoms, while going down the road he would lose oil pressure and here the engine start making noises, not good. He would stop and check the oil and it would be ok. This happened several times and I told him to change the oil and filter that maybe debris was building up on the screen. He did and a few days later the same thing. I told him lets lower the oil pan and see what's going on. He did and found sheets of a light to dark brouwn substance in the pan and It appeared it was coming off the oil pan.

Well guess what it was....? he had been using slick 50 about every 20Kmiles and it was flaking off. Cleaned it all out and still running fine.

Reliably, PdMAnlayst

 

My truck has about 150k and it sat for about 3 weeks for the first time since I have had it. I started it and let it run for about 5 minutes and drove of on to the highway. As I was driving the oil pressure went to zero. I pulled of and checked the oil and it was at the right lavel and golden brown color. I let it rest for about 10 min and started it back up and the oil pressure was fine. But when I drove it I gould tell that the engine was struuguling. I got about 5 mile down the road and the pressure went out again. Question: Is the engine salvageable ? What is the best diagnosis of this problem? New engine or fix current?

 

Did you hear any rattling of the rocker arms or any other clatter type noise when it went to zero? If you did, then more than likely it is real. The

only true way to tell is to put a Pressure Gage where your Sending unit is

and check pressure.

If it starved for lubrication during the times you said you felt like it was struggling then more than likely it has wiped the main bearings and more than probable the cam bearings.

If it were mine I would check actual pressure with a gauge, by turning over engine just long enough to possibly startup and immediately shut off, if I didn't see 7lbs or greater. If that was the case I would look at checking suction screen on pump for debris and possibly replacing oil pump and or see if it is being driven. I had a old ford and the shaft that drives the oil pump from the distributor was broke. I used a drill motor to prime pump before installing new distributor so the bearings wouldn't start dry. During starting is where 95% of the wear on journal type bearings is done.

If you replace pump and pressure is still extremely low, I would check for wiped bearings, which opens up clearances and reduces resistance to flow which decreases oil pressure. Alot of times just the babbit on the bearings is wiped and the journal area is ok, which means just replace bearings and go again.

Let me know how things turn out.

 

My 2000 F150 with a 4.6L had the same kind of problem, but it was only happening when I started it up in the cold and let it warm up before taking off. The engine souded the same so I didn't think it was the oil pressure. It ended up being the oil pressure sending unit. There is some sort of spring in there that goes weak over time and needs replacement. So it would say that I am getting no oil pressure, but I actually was getting normal oil pressure