Ok so I got a 99 camry 2.2 and my oil light came on the other day. So I of course parked it and checked the oil in it and it is right where it needs to be. I dont hear any kind of knocking or lifter ticking in the top part of the motor. I just got hte car not too long ago so im still going thru it and changing fluids and stuff like that. The oil I havent changed yet but its on my list. Any ideas as to what I should look for to fix this problem? I just went outside to start it and it all started just fine, car ran with no oil lite on for about 2 mins and then it came on. Let me know if you need any other info as to I need to get this fix asap.

Thanks ladies and gentlemen.
Buda

 

First determine if the engine really has low oil pressure.

This is done by connecting an oil pressure gauge to the threaded hole where the oil pressure switch screws into the engine block.

You can use a test gauge like the one below or temporarily install a mechanical gauge that would otherwise install inside the car.

Engine Oil Pressure Test Kit

Minimum oil pressure at idle is 4.3 psi. Oil pressure at 3000 rpm is 36-71 psi. Check final oil pressure when engine is warm.

If the oil is at the correct level and otherwise OK changing it will not help.

It is possible the oil pressure switch is bad or the engine really does have low pressure.

The oil pressure switch has one yellow/black wire going to it.

 

Thanks for the response Joey, unfortunatley that didnt fix it. I put a new switch on it and started it up, ran with out the lite on for a couple of mins, then it started flickering and came on then went off and then flickered some more and then stayed on. So I guess its back to the ol drawing board again. Guess tomorrow ill have to go get a pressure gauge and put it on and see what we got going. How hard is it to replace the oil pump on these if thats the problem? Ive never done one but trial and error has always worked for me. LOL.

I did notice some gunk on the old one and around the hole a little. Wonder if maybe I should have tried to clean it out some.

 

Again suggest getting actual oil pressures via a gauge.

As you mentioned gunk. Check engine for sludge. The gunk in the hole could be a sign more sludge issues.

Check the oil filter for plugging, take it apart checking the filter material for sludge The filter should have a bypass valve but could be plugged.

Suggest removing the valve cover and inspecting the valve train for sludge. Removing the cover is easy if you have a tool large enough to get the spark plug tube nuts off.

It is also possible for the oil pump intake filter screen, you will need to remove the oil pan to inspect.

Sludge can plug up the screen and oil passages inside the engine.

However as stated best to check actual oil pressure as you will know if it is low. The oil pump is unlikely to fail, suppose the oil pump pressure valve could be stuck (requires removing oil pan to access).

The crank bearing could be worn enough to cause a lowering of oil pressure.

I suppose it possible for the junk in the hole to plug the hole in the sensor.

 

Yeah pressure gauge is next on my list. I changed the oil filter out today just for good measure. Is there a way to test the wire going into the pressure sensor to make sure it has juice going to it? Im assuming that it has to be plugged in for it to work right. Guess I can slice a part of the plastic off and use a test light. Gotta love the process of elimination. I just dont want to drive the car if theres a serious problem. Guess its a good thing I havent gotten rid of my honda yet.

 

The oil pressure switch is on/off.

When the oil pressure increases above 4.3 psi, the switch opens. If you ground the wire to the sensor, this will be the same as the switch position being closed when the oil pressure is low.

 

Im a little behind on getting this fix as I had 4 kids all week for spring break. Thank god school starts on monday.

So I was finally able to put a manual gauge on the engine and started the car. The line filled about 3/4 full of oil and that was about it, it wouldnt go all the way to the gauge. So it looks like I got low oil pressure. Now heres my question. I know someone said possibly the screen could be clogged or even the oil pump itself could be bad. Is the screen something I can take off and clean and put it back on or even replace it or is it all one piece and I should replace the pump and all? How hard is it to replace the oil pump. Ive never had to do one before so im not 100% sure on how to do this. Im figuring that it isnt too hard to do just time consuming laying on your back under a car in the drive way. I do know that my nephew drove this car for a few months before I got it and he of course being a 18 year old kid never really checked the oil. Im sure he never ran it dry but prolly ran it low a lot. Could it be possible that soem gunk or something got in the screen and is not letting it get the proper amount it need to flow thru it? Thanks for yalls help.

 

The oil in the line can't move to the gauge because there is trapped air between the oil and gauge. To get the air out you would need to run the engine, or crank long enough to build up oil pressure (if going this route take out the spark plugs to ease the load on the starter) with the gauge disconnected from the line until oil came out. Then reconnect the gauge.

If air is in the line it would be compressed by the pressurized oil, the result being the gauge should indicate actual oil pressure.

What pressure did the gauge indicate and at what RPM?

Doubt if it is the oil pump. The pump rotors are turned by the timing belt, not much to break plus the parts are always lubed.

Causes of low oil pressure can be oil pan intake screen plugged with sludge, oil pump pressure relieve valve stuck open, engine worn enough to cause excess oil leakage and lower oil pressure, sludge in engine oil passages.

You might remove the valve cover first to get an indication of any possible sludge condition. This is easy enough if you have a wrench or socket large enough to remove the 4 large nuts on the spark plug tubes.

To remove the oil pan the exhaust pipe needs to be unbolted, then a few brackets, etc.

Toyota may have used form-in-place gasket sealant instead of a hard gasket. If so, the gasket seal will need to be gently broken to allow the pan to drop free.

When putting the pan back on, clean both pan and block surfaces then use form in place gasket material or an auto shop may sell hard gaskets. If using gasket material make sure to wait the appropriate time period for the material to cure (read directions).

Removing the pan also allows access to the oil pump relieve valve. The valve is incorporated into the same engine cover as the oil pump. This cover is on the passengers side of the engine behind the timing belt cover. The hole for the relief valve is on the opposite side of the crank from where the oil pickup tube bolts to the engine.

The pressure valve assy is held in with an internal snap ring. Once the snap ring is out there is a retainer, spring and the valve. Check the assy for plugging or sticky operation.

Check oil pickup screen for built up sludge.

Suppose it is possible there is an air leak where the oil screen pipe bolts to the engine causing the pump to lose prime but doubt this.

Between check under the valve cover, the pan and oil pump pressure relief valve you should be able to tell if there is a sludge issue.

Remember at idle the pressure can be low as posted previously.

 

ok so I put the gauge back on, moved it so the tube wouldnt hit any moving parts. I guess it didnt like being move and it broke the tube near the engine. I heard what sounded like water running and looked and its squirting oil about 8 feet all over the side of my house. So now I have that mess to clean up. So to me it looks like its getting lots of pressure. The compression fitting I have for the engine side needs to be replaced now so I wont be able to put the gauge back on til tomorrow. But I think imma take the pressure switch or what ever its called and take it back and get a new one cause im feeling like it might be that. I put everything back on like its supposed to and ran the motor til it warmed up and no lite on. So I drove the car down the street to the gas station and around the block and it didnt come back on. Then about 500 yards from the house it started flickering on me like its got a loose wire or something.

If it wasnt for bad luick I wouldnt have any at all. And Buddha's are supposed to be lucky. lol.

 

Best to take pressure readings, otherwise just guessing. If the pressure really is low the engine could be damaged.

The pressure sensor switch only comes on when the pressure is below 4.3 psi. Not a lot of pressure when engine is at higher RPM's.