OK so I am going down the road yesterday and I had to slam on the breakes as traffic came to a hard stop. Once I stoped I hear that tone coming from that dashboard telling me I have a problem.

The oil presure seamed to drop off and pick back up again. I got to where I was going and it sat for a good two hours. Got back in the truck and headed home keeping my eye on the gague. It was holding at 30 to 35 psi and that has been normal for the truck.

It took me 45 mins to get home and all of it highway, Once I got off the highway and came to my first stop sign I got the tone again and no pressure. As soon as I hit the gas a little that presure comes back. So this morning I drove it to work (15 minute drive) and everything went well untill I got in the parking lot

Atidel 650RPM the gage went to zero again, with a little tap on the gas it picks back up. I did notice that if I ran the rpms high (in park) the engine would stumble slightly at low rpmsand once the RPMs settled to 650 the gage would go to zero. Now with it hot and in park I could shut the engine down and start it back upwith no problem.

Thanks forany advice

 

I had a similar problem with a brand new oil pump when I installed my 360. Found out that it was a cracked case on the oil pump that was small enough to not affect much at higher RPM, but had zero pressure at idle. Replaced the pump with a new Melling High Volume and been fine since.

Pulling the pan and replacing the oil pump is not real hard on our trucks. My 4X4 only needed the starter and transmission to engine brackets removed and the pan came right down and slid out. Be very careful when installing the new pump that it mates exactly with the block before you tighten the bolts or you'll crack it also. If you cannot clean your pickup screen compeltely, purchase one of those too and install it.

 

First question....DO you have enough oil?

 

I had made that assumption, but it should have been my first question.

 

I had a cherokee that had low oil pressure. I used that lucas oil stablizer and one quart of 15 40. It never happened again.. bt with your case I would definatly check to make sure that you have the correct amount of oil. Also oil pressure sensor?? Maybe.. My honda had that go bad. then it would only read when I was cruising.

 

my caravan does that when its too low on oil.. fill it up and see what happens

 

You could be low on oil, it could be our sending unit, oil pump, crank/bearings. First thing I would do is check the oil to see where its at, If its good go ahead and hook up a mechanical oil pressure gauge to see what your oil pressure is really at. If its still low I would put a new oil pump in. I did that in my truck and the oil pressure was still low, it turned out that my main and rod bearings where worn to sh*t and my crank was scored as hell. I put new bearings init like a retard and theoil pressure was still bad.I pulled the motor and crank andthe new bearings I put were still screwed. now its getting a rebuild. I hope thats not your problem.

 

Check the sending unit, I know some sending units have a diaphragm in them, when they age its cracks, when the motor warms up, the oil seaps through the diaphragm giving you an incorrect oil pressure reading

 

oil filter clogged, pump maybe, or mabe its low

 

Thanks for all the help, It is not low oil. So that leaves me with oil pimp and sending unit to start with thanks for all the help.

Ray