No oil pressure on startup!

[blackrob]

So this just happened the 2nd time in couple of weeks. I start up the car and it idles rough and the oil light is on and the oil pressure gauge is pegged at zero. If I just give a slight push on the gas, take it to 2K RPM's, the oil pressure kicks up and the oil light goes off. It's a 95 VR4 with 151K miles. I just bought the car about a month ago and the guy told me that the motor had been rebuilt about 7k miles ago.

[green-lantern]

Damn that is scary!

[mikeyVR4]

So this just happened the 2nd time in couple of weeks. I start up the car and it idles rough and the oil light is on and the oil pressure gauge is pegged at zero. If I just give a slight push on the gas, take it to 2K RPM's, the oil pressure kicks up and the oil light goes off. It's a 95 VR4 with 151K miles. I just bought the car about a month ago and the guy told me that the motor had been rebuilt about 7k miles ago.

I suggest to not turn the car on anymore if that light shows and the car is running rough at first. If you car truly has no pressure you can damage your engine.

This might be a stupid suggestion but its something to look at first, check your oil levels and see how you are doing. I know some people say to check the sensors but since your car is running rough when that light is on it may mean that the indicator light is true in its readings.

[mcshooter]

the oil pressure switch . maybe but the rough idle scares me. you might take the oil filler cap and look to see if you have oil pressure

[Ninja Performance]

If the car is idling rough, and very LOW rpm, your oil pressure will drop and the idiot light will come on.

Maybe it's not low oil pressure that is your issue, but a poorly running engine.

-Chris

[green-lantern]

If the car is idling rough, and very LOW rpm, your oil pressure will drop and the idiot light will come on.

Maybe it's not low oil pressure that is your issue, but a poorly running engine.

-Chris

I was thinking this. Also check your oil pan for dents if you haven't already. It doesn't take much of a dent at all to choke off the oil supply.

[fastnelson]

At 2k rpms where the oil pressure goes?

Add:
1-Why is running rough? you have to fix that.
2-What oil do you use.

[thor'svr4]

just fyi i spun a bearing when my low oil pressure light stayed on at 800rpm, but it went off by 900-1000 rpm. so if yours is on at any rpm higher than idle i would be scared.

[mikeyVR4]

just fyi i spun a bearing when my low oil pressure light stayed on at 800rpm, but it went off by 900-1000 rpm. so if yours is on at any rpm higher than idle i would be scared.

Yeah that is why I am advising him to not start the car...ESPECIALLY if that light keeps coming on and the car running rough. Don't risk your engine. Oh and please do not REV your engine when your car isnt running well....that is something I would never do.

[MaxClass]

You might consider the oil filter. If it's a "Fram" take it off and throw it away. I use a K&N because they are known for better stuff and they also have a 1" nut on the bottom to make removal easier when your under the car. Could also be oil draining backwards from the filter leaving the engine to have to suck oil from a pump full of air. Most oil filters have an anti-drainback flap in them so if the filter has a manufacturing defect that could exacerbate the problem but the filter is the first link in the chain to getting oil to the rest of your engine so that is the first place I would start to look for problems.

P.S. As posted earlier make sure that you do not have a dented in recess on the bottom of the pan. Unaware people put jacks there to lift up the engine and dent them.