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2008 Cobalt Spun Rod Bearing but is Running Again!?

My 2008 Cobalt apparently starting burning oil without my knowledge about a week ago. (I had literally checked the oil a week prior!) Anyhow, it started making a horrible rattling noise, at which time I pulled over. No lights came on, (oil, engine, etc.). Not sure if it was the right thing to do or not, but I was close enough to a gas station to actually be able to put my hazards on and drift into its parking lot in neutral. My stepfather and father in law are both mechanics, (I am lucky!!)…father in law came to take a look and pick me up and we had it towed to his shop. He drained the oil and there were metal shavings in it. He said the engine was probably toast, but he wanted to order a new bearing and put clean oil and drain it 3-4 times to see if that would do anything. He called the next day and said it was running, he’d driven it about 30 miles round trip and it ran just fine. He said he couldn’t believe it and it really should NOT be, but it was. He waited til the following day and took it on the interstate and again, everything was fine. So my stepfather asks how it’s doing, and I share the good news with him. He told me that he agreed it was shocking, but it would likely do the same thing and die for good within a day or two. Now I’m super paranoid and am not sure what to think. His advice was to trade it in while it was still running, which I’m not sure I feel good about on an ethical level. I honestly can’t afford to trade it in for something more expensive right now, and financing something else is not ideal currently. My question is whether my stepdad is right, that it’ll probably last 1-2 days, or if there is a possibility it could continue to run ok for me for awhile. Additionally, if I do continue to drive it, are there any factors to consider, (i.e. avoid interstates, don’t go above a certain speed, etc.)? Thanks in advance for any advice!

You dodged a bullet for sure. The engine may have a some sludge, a glob of which may have starved a portion of the engine for a moment. You shut it off quickly enough to avoid major damage. A flush and re-start got it going again with few issues.

I’d ask; Did your step father installed a mechanical oil gauge to see what the pressure is shown upon startup, to warm idle to running down the road? If that looks OK, you are probably good to go until, of course, that oil burning problem sidelines the car. Also, if your step father didn’t drop the oil pan and a few rod caps to look at the bearings, his comments are just an opinion even IF he took pressure readings. An educated opinion, but still an opinion.

Our comments are opinions, too, but less so since we aren’t at the car. I’d make sure an oil pressure test gets done, if it hasn’t already. If that shows OK, drive it any way you want. If it blows, it blows. If it gets you down the road long enough to save for a new-to-you car, great!

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Thank you so much! I’ll defin ask about the oil pressure test. I suppose if all is well it goes without saying that I should check my oil daily from now on, too? Thank you again, you’ve eased my mind a bit! :slight_smile:

So they removed the oil pan and replaced the one failed bearing from below? Or they just added oil, and it quieted down for now?

There’s a decent youtube on a guy using sandpaper on the crank and putting a new bearing in on a spun bearing. Seemed to then run ok but never know for how long. The unanswered question though is why did it start using oil in the first place to cause the oil loss?? That might be more the issue but yeah, time to start looking and maybe saving. Often we need to replace cars on the car’s time line and not ours.

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You’re talking about the video with all the religious preachings, where the guy is working on a Nissan Sentra?

No, the Hispanic guy. Didn’t see anything religious. Said he buys 2-300 cars a year and was going to give this Hyundai to his uncle. It was the I4.

Link, please? I’d like to watch it.

Yes, that’s true…thanks so much!

Yes, he removed the oil pan and replaced the bearing and then added/flushed the oil several times to remove any debris. It seems to be running like normal…

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With two mechanics in the family, if this motor gives up the ghost (it likely will), it should be relatively inexpensive for you to have a used one put in.

I must have been mixing up two of them. First is the spun bearing, Second is the Hispanic guy.