Hello, I'm new to the forums here, so apologies first if this is is the wrong place. Additional apologies because this is gonna be a long post.

I just bought my Neon on Friday the 25th. It has just over 77k miles on it and it drove the nearly 100 miles home from where I got it with no issues.

The next day I pulled out of my driveway and noted there were no oil stains on my driveway, which was nice and something I had worried about potentially being an issue.

On the way home from the store the car threw its check engine light at me and shook pretty hard then settled back down and I finished the 2-ish miles home. While it was shaking (less than 5 seconds probably) I looked in my rear view to see if I could slow down safely, and saw a black piece of something bouncing off the road behind me. This was a little alarming but I was more worried about the shaking and getting the car home than stopping to see what may have fallen out onto the highway behind me.

Upon getting home I did some looking online and found the key trick to get a code and it was a P0340, Camshaft Position Sensor, which I had my brother in law, who is a mechanic, replace. Code has not been back since. also cleaned the battery terminals and contacts because they were pretty corroded.

On Tuesday I noticed a small oil spot on my driveway when I was leaving to go to get some tires for the Neon since it really needed them. I asked the guys at the tire place to see if there were any oil leaks while it was on a lift and they said they saw none. So I assumed maybe the puddle in the driveway was actually run off from cleaning the battery the other day.

And then we have today. I get outside and look at my car and driveway and can see a huge oil spill under my car before I'd even gotten in and moved it down the driveway. I backed my car down the driveway and took a photo. I also placed a white napkin on the spill and it came up looking like I had set it in fresh, clean engine oil. So I drove to a nearby gas station and checked my fluids, and everything read as full and the car was running really well, so I was (and still am) a bit baffled. texted my brother in law and he took a look from the top and couldn't see anything alarming and when I drove away from his place I noticed that there was not much oil left behind where I had parked the Neon.

So I kinda have a theory that the car is leaking when it is cold (it got down to 17F last night) and then when I drive a while the engine heats up and where ever the leak is gets plugged or slowed by the expanding material around it. But that doesn't explain why it has no signs of oil inside leaking/dripping anywhere, unless the leak is in the very bottom of the engine, in which case I would assume the tire guys would have seen it.

Any suggestions on where to look for a hidden oil leak would be great, because everyone here is at a bit of a loss.

 

Welcome to the 2nd Gen Neon forum

Which driveway leak in the photo are you talking about, the Large or small one? What color is the leak fluid & does it have a water, or oil like feel & viscosity?

 

The big one in the photo is the one I was focused on. The little one was from the day before when I parked lower in the driveway to see if it was leaking, and then I pulled it up to be over where the big oil stain developed that night while it was sitting in the cold.

Leak fluid is colored like pale honey and is definitely oily.

Today I checked my oil levels again and its at about half way, or maybe just over half way, to the max full oil line on the dip stick. And a friend of my mom plugged in a "Blue Driver" scan device and it showed that my car had low oil, but didn't say how low, and didn't find anything else.

My best guess at this point is oil pan gasket needs replacing since the oil is still no where to be seen from above. I plan to ask my brother in law to look at it this weekend or take it to a mechanic elsewhere next week.

Other than the oil leak I am getting to like this car more every time I drive it. Like the drive home I liked it, the next day I hated it and now I am not seeing other issues pop up besides the oil leak, and if that can get fixed it seems like it'll be a decent car for me to have for a while. I just can't have it hemorrhaging oil all winter.

 

OK, well I was going to say if it was the Big stain, there was no way all the fluid levels could look ok. Since the last repair made was the Cam sensor, have BIL look closely at his replacement work, to make sure all is tightened up properly & the new part is ok. Just because its new doesn't automatically earn it a pass, I've seen bad new parts right out of the box.

Also check / replace the PCV valve, as if its clogged up,or sticking, it can cause a crankcase over pressure that can cause the weakest seal or gasket to blow. There is a specification for max crankcase pressure from blow by can likely be looked up in the manual sticky atop the forum thread index page.

If you come to suspect the oil pan gasket, maybe try retorquing the pan bolts, the torque spec is also listed in the manual.

EDIT: Forgot to suggest inspecting the oil filter for tightness & its gasket. Double gasketing will cause them to leak like a sieve too.

More thoughts for consideration, let us know what you find.

 

Brother in law just crawled under the car and could not find anything that looked leaky, everything looks good and sealed well and not drippy/oily. He checked the dip stick and it read full, but he said the reason it was low when I looked was the slope of my driveway is too steep to get any good fluid level readings. I should have remembered that from a previous car that I over filled with oil once on my driveway. Whoops.

So now the best guess based on current evidence is that it was over filled, and pooled somewhere then drained on my sloped driveway. On Tuesday I am going to be cleaning my driveway and we will see if it has any issues this coming week.

It is driving really well at this time, so here's hoping it's a fluke and not something that will turn into a long term and expensive "chase the oil leak" issue.

 

Yes the Owner Manual states we need to make sure the vehicle is sitting level, side to side & front to back when we check, change, or add fluids, so its measured accurately..

Another thought on the oil checking & loss. When & After checking the oil, make sure the dipstick is Fully seated. If it isn't Fully seated, until we feel & hear it sorta click in place, crankcase pressure can cause it to back out enough that oil can blow out & run down & drip off the dipstick tube, but not likely as much as the Large stain was showing, unless you had Seriously overfilled the crankcase, because the vehicle wasn't level when checked.

For a while, keep a Close, maybe daily watch/check on the engine oil level & let us know how it goes. More thoughts for pondering.