95 Stratus 2.5L Oil Light

[Hartsock]

Popular topic I know. Just picked up a 95 Stratus ES with the 2.5L engine, 107,000 miles. After the engine has warmed the oil light flickers or comes on while idling in gear. Shift to Neutral or slight pressure on gas makes light go off. 750rpm seems to be where the light goes off. The engine is revving smoothly and there are no unsettling noises coming from it.

Today had the oil pressure sending unit replaced and the problem is still there.
What does the troubleshooting tree look like from this point? First check the actual oil pressure. What are the most likely trouble points?

Dana

[AZeline]

It sounds like you have low oil pressure. I don't know your engine specifically, but most have an oil pump inside the crankcase. It's usually powered by the internal parts and when the idle goes down, the pump slows down. Something is causing the oil pressure to drop below the limit of the switch. It could be your oil pump isn't as efficient as it once was, or something is restricting the pick up of oil from the pan. Or some of the components inside are doing a poor job of keeping the oil pressure where it's needed. Sometimes it's the bypass that's failing (springs and seals inside the system or pump are just getting old) and it is relieving the pressure to quickly. It's probably accessible by dropping the oil pan, so repairs aren't to painful.

Check with someone who knows about this so they can help you find the exact problem. It might not be as bad as some might think. Just don't start worrying about a rebuild just yet. Check out these things first.

[Hartsock]

Man, my first reply lost in the electrons.

I don't know a heck a lot about engines other than how to change a battery or the oil, maybe a starter in a pinch.

When you talk about the bypass, this is where?

I have a couple observations. First I added a bottle of STP oil treatment and the oil pressure light comes on less often at idle in gear. Second, there is a small amount of oil leaking from one spark plug of the three I can see. The other three are well and truly hidden under the air plenum in this engine. I suppose the best case there is a bad valve cover gasket. But that would not explain the low oil pressure, as I understand things.

We don't have a lot of money to throw at this problem so want to proceed in the most efficient way but don't want to lose the engine to low oil pressure. So next it would be best to have someone check the mechanical oil pressure and pull the pan?

Considering holding my nose and taking the car to the local Dodge dealer to check this out, figuring they have the best knowledge of the trouble spots for this engine. But I'll have to pay for it. As I understand it the timing belt has to be removed to work on the oil pump or water pump. I don't know if I can save some money by doing a 3fer, having the oil and water pump checked out while replacing the timing belt as well. Or whether they will just charge the book rate for each repair? Since I don't know if the belt has ever been replaced it seems like a prudent thing to do.

Dana