Oil dipstick malfunction?

faliray

Good morning. I'm having a problem with my 2007 Chevrolet Cobalt. The other day I checked the oil. I was alarmed to see the dipstick was bone dry. I added half a quart. Later that day I pulled the dipstick out after the car had been sitting a while. It showed oil at the max level. I wiped the stick and attempted to check the oil level. Again bone dry. I added another half quart and checked it the next day using the same procedure. Same results. Full when I first pull the dipstick out, bone dry after I wipe it. What's going on? I know the vehicle has oil in it.

imidazol97

How do you know there is oil in it?

What you need to do is change the oil so you know it has 5 quarts in it. Then take a reading on the dipstick after wiping it and reinserting it.

Oil can hang on a dipstick after being splattered there when the level in the pan is not at that level.

faliray

On the two occasions I pulled out the dipstick, after the car had sat level for a while, the level was at the max line. No oil stains under the car, either. I'd planned on taking your advise, though. I'm changing the oil this Saturday. I plan on measuring how much oil drains out of the pan. I'll also put the recommended amount of oil in the car and check the dipstick. I just hope I haven't been inadvertently starving the engine of oil. The engine sounds like it's running fine. One last thing, I put in 10w 30 the last time I changed the oil. The engine is supposed to take 5w 30. Thanks for your answer.

thecardoc3

10W30 is not only way too thick for that engine, it doesn't meet the engine's requirements to prevent sludging. As I read your description, there is oil on the stick when you first pull it out, but nothing on it after you have wiped it off and re-inserted it into the engine. If that is correct then your oil level is too low, at least at the moment you are checking it.

faliray said:

The other day I checked the oil. I was alarmed to see the dipstick was bone dry. I added half a quart. Later that day I pulled the dipstick out after the car had been sitting a while. It showed oil at the max level.

That oil was likely just sticking to the dipstick, that's why it needs wiped off and rechecked.

faliray said:

I wiped the stick and attempted to check the oil level. Again bone dry.

Then there isn't enough oil in it.

faliray said:

I added another half quart and checked it the next day using the same procedure. Same results.

The one possiblity that wasn't really clear here was whether the car had just been driven for a while or not. If an engine is getting sludged up, oil can get trapped at the top of the engine and take a while to drain back down to the pan.

faliray said:

Full when I first pull the dipstick out, bone dry after I wipe it. What's going on? I know the vehicle has oil in it.

If it has been sitting and this is what you see then the oil level is too low. The biggest concern is using the wrong engine oil causes some pretty serious issues, and one of those is increased oil consumption as well as the sludging. By chance is the oil that you see on the stick before you clean it off somewhat thick appearing and dark? Remember what it looks like because it might be important in the future. When you change the oil, look at what it looks like on the dipstick before you start the engine, take pictures of it if you need to. Then watch to see how fast the new oil get's dark. An engine that has been serviced correctly will have the oil barely darker than when it was put into the engine four to five thousand miles later. Engines that have a lot of build-up in them from the oil failing can turn the new oil dark in a couple of trips around the town.

One other thing that you coud do right now would be to have an oil analysis performed. That will tell you more about the condition of your engine right now than anything else could.

Mr_Shiftright

Oil Analysis:

https://www.blackstone-labs.com/

(This is just one of many labs offering this service).

imidazol97

I had oil analysis by Blackstone years ago just to see how the oil life was going on my leSabre with 90K mi on it. They reported by phone that I had Na and K in the oil (sodium and potassium)at low levels, which meant I had coolant getting into the oil. They said change the manifold gaskets soon or change the oil every few thousand miles to prevent build up. Well worth the $20 or $25.

Save a sample of the oil in a clean bottle when you drain it in case you decide to do oil analysis after Blackstone ships the sample containers to you.

If your car is working great despite a low oil level due to the 10-30 oil and sludging, I would start putting in full synthetic 5-30 and running the oil for short change periods. Or at least use a blend. I dont' think that's much cheaper than Pennzoil Platinum these days. Watch the oil color as the solvents in the new oil pick up the contaminants and change the oil at 2 or 3 thousand miles a couple of times along with a new filter.

An option would be to use regular oil for a few changes and change every 1000 or 2000 miles. It would be really cheap and like an initial flush.


Personally I would not add anything to those oils that they try to sell over the counter. Just let the fresh additives in whatever oil you use pick up contaminants from the rings and the variable valve actuators. And remove the oils early while additives are still stronger and replace with fresh oil with fresh additives.


Watch the level on the new oil you put in.

How many miles are on this Cobalt? I'm at 116 k or so.

faliray

I really appreciate everyones help. Thank you. I put the wrong weight of oil because Im used to my Neon. It took 5w30 or 10w30 depending on the season. Im going to change my oil in a few minutes. I plan watching the level more closely from now on. I plan on changing my oil every 3000 miles with the correct weight oil.

thecardoc3

FYI. The "correct" oil would be a 5W30 product that is certified to meet API SM, ILSAC GF4 AND GM's 6094M specification.

Those specifications are now revised to API SN, ILSAC GF5 and dexos1. (The 6094m is obsolete) When GM came out with the dexos specification they required that it be licensed in part because the GM 6094M requirement was largely over-looked. The licensing requirement put the specification on the front of the bottle making it easier for consumers to choose a product that actually meets their vehicle specifications.

faliray

Heres a quick update. Its been 2000 miles since I changed my oil and put STP 5w 30 oil in the car. I checked the level last week and it was just above the add mark. I think the isses I had were due to me putting the wrong weight of oil and leaving it in the car too long.

faliray

Thanks for everyone's help and advice.

faliray

My Cobalt continues to burn oil. About half a quart every thousand miles. Is there anything I can do to slow the rate the vehicle is burning oil? Would a high mileage oil help?