Oil and Engine Indicators on with Full Oil? Issues & Solutions

Causes & Fixes of Low Engine Oil Lights (When Oil Levels are Fine)

Bad sending unit Also known as an oil pressure sensor, the sending unit is the electrical component responsible for relaying the oil level to the vehicle’s central computer. If the oil sending unit has gone bad, your vehicle’s check oil light will pop on even though there’s nothing wrong with your oil levels. Other symptoms: None. If you have zero other problems with your vehicle and you’re positive the oil levels are fine, the sending unit is likely to blame. The repair: See a professional mechanic to have the sending unit replaced. Cost to repair: This is a relatively easy repair for a mechanic, so you’re likely looking at $50-200 depending on the cost of the sending unit for your make and model.

Faulty oil switch There are two electrical components involved with your oil pressure warning light. The sending unit monitors the level of the pressure and the oil switch, which pops on whenever the sending unit tells it the engine oil levels are wrong. If the sending unit is fine and the oil levels are appropriate but the dashboard light still won’t go off, it’s probably a bad oil switch. Other symptoms: Like a bad sending unit, you won’t have any additional symptoms. It’s more likely that the sending unit goes bad than the oil switch, so only assume the switch is bad if you know the sending unit is okay. The repair: Visit your mechanic to have the switch tested and replaced as needed. Cost to repair: Expect to spend anywhere from $130-350 depending on how complicated accessing your dashboard’s switches is for the mechanic.

Incorrect oil Different vehicles require different oil viscosities (this is what the 5W-30, 10W-30, etc. on the oil cap refers to). If you’ve accidentally added the wrong oil to the vehicle, the vehicle may detect lubrication issues even if your oil levels are fine. Other symptoms: If you just added oil, check the label on the oil cap to see what kind of oil you need, and then look at the label on the quart you just added. If there’s a difference, the wrong oil is to blame. You may also notice smoke coming from your engine, bad mileage, or strange noises if you keep driving. The repair: You can replace this one yourself if you know how to change your oil! Just change the old oil out and use the proper oil this time. Cost to repair: A new quart of oil will run you $5-15. If you have a mechanic change your oil, it should run around $40-60.

Bad oil pump The oil pump is responsible for circulating the oil through your engine to keep the components lubricated. If the pump is bad though, that oil won’t actually flow—it will just sit in the oil lines and reservoir. This will cause the oil pressure light to pop on. Other symptoms: Your engine runs hot, you hear strange noises coming from the engine bay, and your mileage performance is poorer than it normally would be. The repair: The pump needs to be swapped out, so see a mechanic to have them wire a new pump. Cost to repair: This will likely run $100-500 depending on the type of pump. For some vehicles, it can run all the way to $1,000 if the pump is especially hard to access.

Blocked oil filter Also known as an oil strainer, the filter is responsible for absorbing any debris or contamination in the oil so that it doesn’t continue to circulate through your engine. If that filter is blocked up though, it could keep the oil from circulating smoothly. This could trigger the oil pressure low indicator, even if the levels are technically fine when you check them. Other symptoms: Knocking noises, engine sputtering, overheating, and dark exhaust fumes are all symptoms of a clogged filter. You’re also more likely to have a blocked filter if you’ve changed the oil multiple times over the past few years but haven’t changed the filter out. The repair: The filter needs to be swapped out and the oil needs to be changed. You can change the filter yourself if you’re handy! Otherwise, take it to the mechanic. Cost to repair: Changing the filter and oil yourself shouldn’t run more than $30-100. If a mechanic does it, you’re probably looking at an additional $60-100.

Worn-out engine If your vehicle is old and you’ve got an engine with hundreds of thousands of miles on it, the oil may not circulate as smoothly as it used to. This is common when an engine is nearing the end of its life. As the oil flows inconsistently, it will eventually trigger the oil pressure low warning you’re seeing. Other symptoms: Your oil leaks, your engine overheats, you hear odd noises coming from the engine, and your engine struggles to start (especially in cold weather). The repair: At this point, there is none, unfortunately. You’re probably in the market for a new engine (or new vehicle). In some cases, you can rebuild the engine, but if it’s very old it’s probably not worth your time and money. Cost to repair: An engine rebuild can run $2,500-4,000. A new engine may run $4,000-10,000.

How do I know if my oil levels are fine?

Check your engine oil dipstick to see if the oil is low. With a completely cold engine, pop the hood and locate the oil dipstick (it’s usually red or yellow and has a little oil logo on the handle). Pull the dipstick out, wipe the oil off, then insert it again into the reservoir before removing it again. Look at where the oil residue is located. If the oil is at or near the “full” line on the dipstick, your oil is full. If the oil is actually low, adding oil to your engine should solve the problem. The color of the oil on the dipstick matters, too. Healthy oil should be a soft brown (almost orange). If it’s black, the oil is degraded and you need an oil change.

Can I drive if my oil pressure light is on?

You can drive if there are no additional symptoms. If your oil level does appear to be fine and there’s nothing else going on with your vehicle, you’ve probably got a minor electrical issue. You should be okay to drive so long as you don’t have any other performance problems. A bad sending unit or oil switch does need to be addressed eventually, but it’s by no means an emergency.

You can’t drive if you see smoke, smell burning, or have performance issues. Any of these symptoms indicate something actually is wrong with the oil distribution in your vehicle, and an oil issue could potentially lead to an engine fire. Beyond that, improper oil flow can be catastrophic for an engine. Even if you don’t have a fire, you could cause serious damage to your car by continuing to drive.