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Oil light still on after oil change

edited November -1 in Repair and Maintenance
I have a 2003 Dodge Neon with about 90K miles on it. I didn't think my car was due for an oil change, but since the oil light was on I got one anyways. Everything seemed fine for about 2 days, but then the light came back on. Now it comes on about half of the time. I just checked the oil level, and its fine. Is there any reason why the oil light only comes on sometimes?
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Comments

  • edited April 2010
    The "oil light" is not an oil level light, or a change your oil light. It is an "oil pressure" light. It comes on to tell you when you have no oil pressure which means no oil flowing inside the motor - which is bad, very bad. A motor will seize up, stop running, and you'll need a whole new motor if you run it without oil pressure.

    You should have the car towed to a mechanic and have the car checked to see if you have oil pressure or not. It could be a faultly sending unit telling the light to go on when in fact there is oil pressure. Or, it could be your oil pump has failed and there is actually no oil pressure. Running the motor is risky unitl you know for sure what is going on.

  • edited April 2010
    Here we go again.
    At least twice each month, we get questions in this forum from people who have destroyed their engine because they did not understand the function of the "oil light" on their dashboard. For your sake, I hope that I am wrong.

    If this "oil light" is the type that I suspect it is, then it is a warning that the engine's oil pressure is dangerously low, and that the engine should be immediately shut down in order to avoid engine damage.

    Some cars have a light to indicate the need for an oil change, some have a light to indicate a low level of oil in the crankcase, but ALL cars have either a warning light or a gauge to warn of low oil pressure. Since the Neon is a "low end" car, I suspect that the only one of these lights on that car is the latter type--and this portends problems for you.

    It is possible that the engine's oil pressure sensor is defective, and is causing the light to come on by mistake. It is also possible that poor maintenance has led to oil sludge in the engine, and that the engine's most sensitive parts were deprived of normal oil pressure, with resulting engine damage. It is also possible to have a defective/worn out oil pump, but this is very rare.

    So, my suggestions are as follows:

    >DO NOT start the engine or drive the car for the time being, at least.

    >Open the glove compartment, take out the Owner's Manual, and read the section on dashboard warning lights and gauges in order to determine the exact nature and function of that "oil light". If it turns out that the "oil light" is an indication of the need for an oil change, then perhaps it just needs to be reset by a mechanic.

    >If it turns out that the "oil light" is an indication of low oil pressure or a low oil level, then you need to have the car towed to a competent mechanic for examination of the engine. If you are very lucky, the problem may turn out to be merely a bad oil pressure sensor or a bad oil level sensor. If you are not lucky, you will likely need a new engine.

    Please do us a favor and post back with the exact wording from your Owner's Manual regarding the function of that warning light. I am very curious to hear what the manual states about the "oil light".


    If it turns out that this light is a warning of low oil pressure, the saddest part of this whole scenario is that engine damage could have been avoided by simply taking some time to familiarize yourself with the function of the warning lights on the dashboard. Yes, I know that we are all very busy nowadays, but by not taking perhaps 15 minutes to read that section of the manual, you may have cost yourself a few thousand dollars.

  • edited April 2010
    You mention checking the oil level NOW. Were you in the habit of checking the oil level BEFORE this oil light incident?

    If the answer is NO and this is a red oil light that was on previously due to little or no oil then the engine is likely trashed. Changing the oil is an exercise in futility and in my opinion whoever changed the oil should have refused to even touch the car if the prior sentence applies.

  • edited April 2010
    You're right, it is an oil pressure light. Thanks for the advice. Obviously, I'm now freaking out that I may have ruined my car but I'll get it to the shop tomorrow (I checked, they're all closed on Sunday). Is there any hope in the fact that it doesn't come on all the time -- could it just be a faulty sensor? Is there any way of knowing without taking it in?
  • edited April 2010
    "I'll get it to the shop tomorrow"

    I really hope that you meant that you will have it TOWED to the shop tomorrow.

    No, from afar nobody can tell you whether you have a defective sensor or not. Only a mechanic can determine this, in person.

    If the oil pressure light comes on only some of the time, that MIGHT indicate badly worn bearings, or a weak oil pump, or the wrong viscosity oil. However, engine damage is probable as a result of your negligence, and starting and running the engine at this point will exacerbate the damage. If you want to have any hope of salvaging this engine, you will do as I suggest.
  • edited April 2010
    After the oil change, the light did not come on for a couple of days and now it comes on about half the time. Does the light primarily come on when the engine is idling after warming up? If that is so, it does not mean that no oil is flowing or there is no oil pressure, it means that the oil pressure is below 7 psi.

    This is typical for an engine that is pretty much worn out. I would have your mechanic check it out because it could be something as simple as a leaking oil pressure sending unit. Have you been losing oil between oil changes?

    If you have an oil leak that is causing this, you should get it fixed. If not, then you may have to make some decisions. Is the vehicle worth putting a remanufactured engine in? If not, and there is no simple repair, you might try using a heavier weight oil, like 15-40 or 20-50. A 15-40 Diesel grade oil such as Delo or Rotell would be my choice as those oils still have the recently banned anti-wear additives that would provide some protection during the low oil pressure times.

    A good check by a mechanic will take some of his time, be prepared to compensate him for this, but it would be money well spent. Go to a independent mechanic with a good reputation, you will get a little more personal attention on this.
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