Years ago, an airline mechanic improperly installed three chip detector plugs on a L-1011 airliner!!!
As to checking for damage that could involve 2 processes.
The easy one would be an oil pressure test which may, or even may not, reveal a problem. This could be especially true if a heavier oil was used after the tow-in or the oil was doctored to stiffen it up a bit so to speak.
The more complicated one, and the preferable one in my opinion, would be to drop the oil pan and remove a few crankshaft bearing caps. Any caps removed should be ones that are located the fartherest away from the oil pump as they are the last in the chain to receive oil pressure.
If the bearings show signs of the overlay being scrubbed off, scoring, or galding then you run into the issue of replacing the bearings and worse, if the crankshaft shows signs of a problem. The latter would involve major surgery; meaning removal of the motor and replacement or regrinding of the crankshaft.
We’re all human and can make mistakes. I’m not a mechanic by trade, but have been working on my own cars and sometimes the cars of family and friends to save them a few dollars for about 36 years. I always do my own oil changes as well. I’ve driven about 1,000,000 miles in the 36 years since I started driving so I’ve done my share of oil changes. About a year ago I was changing the oil in one of my cars, I had started pouring the oil back into the engine when I suddenly remembered I’d not put the oil plug back in the oil pan, but was able to catch it before all of the first quart had ran out on the ground. Since then I’ve made it a habit to double check that the filter is in place and tight and check that I’ve put the oil plug back in and tightened it down. Even after double checking everything I always start the car up make sure the oil pressure light goes out and let it idle a few minutes while checking for oil leaks at the filter and oil plug. My dad also changed his own oil as long as he was able, yet he had a filter gasket stick to the block one time and he didn’t notice it when he put the new filter on. A few days later his oil pressure light came on, that’s when he found the extra gasket between the block and filter. Hopefully there’s no damage to your engine, but if it is the shop should step up and pay for the repairs.
It looks like the answer to your question has been answered. I would like to modify the title of your question to: It amazes me how a “quickie oil change” business can mess up something as simple as changing oil and still get customers year after year!
I know that mistakes can and will occur from time to time but these “quickie oil change” places have it down to an art form.
Since you had a large puddle of oil under the car when you came out, I would assume that there was still some oil in the engine when you shut down, so engine damage is unlikely. You probably never had an “oil light”.
That puddle of oil could easily be made by a small amount of motor oil. A half cup will spread out and create a large blotch but won’t do much for oil pressure. Odds are that oil in the puddle was residual oil draining out of the cylinder head and oil galleys.
If the drain plug just fell out shortly before the car entered the parking space then there should be a trail of oil leading out of that space instead of a blotch because an oil pan with no plug is going to empty PDQ.
If there’s no oil trail then the oil pressure light had to have been illuminated.
Don’t you hate it when those nosy cops investigate suspicious activity and end up taking interesting people like drug dealers, car thieves, vandals, and burglars off the streets? If they would just mind their own business, all these fine folks would still be around to entertain us and make our lives more interesting.
“If the drain plug just fell out shortly before the car entered the parking space then there should be a trail of oil leading out of that space instead of a blotch because an oil pan with no plug is going to empty PDQ.
If there’s no oil trail then the oil pressure light had to have been illuminated.”
Exactly! It would be one thing if the drain plug was sitting in or near that puddle, but doesn’t appear to have been the case.
Do we know that there wasn’t a trail of oil just because the OP didn’t mention it? A half cup of oil on asphalt wont spread out like it would on concrete so it could have been quite a bit of oil. Remember the OP said huge puddle of oil and it was still draining as it went onto the tow truck.
Granted, a few details would help to clarify that part of the problem. If there is no oil trail leading into that parking spot this means one of two things has happened.
- The drain plug fell out as the car came to a stop. This means the full load of hot oil should have created a lake underneath the car and the drain plug should be lying in the middle of the lake.
- The drain plug fell out who knows where and there wasn’t enough oil in the motor to leave a trail.
As to the OP seeing oil drain there could be a reason or two for that. When I change the oil in my cars I allow them to drain for 20-30 minutes and they’re still dripping at the end of that time.
Assuming the car went onto the tow truck nose or tail high it could be that residual oil is now sloshing over from any cubbyholes where it was pooled and is now draining through the drain plug hole.
I for one would like to know if there was an oil trail or not and whether the drain plug was lying underneath the car. Just speaking from my personal experience I’ve seen a number of trashed engines and transmissions due to a missing plug but have never seen or heard of one that happened while the car was at rest.
I’m not saying that a plug can’t fall out on a stationary vehicle; only that I’ve never been part of it.
The oil Pressure light wasn’t illuminated when I pulled into the parking space. And trust me, I would’ve known if the light was on. I do pay attention to the dashboard. I know what warning lights indicate. I used to own a 1999 Chevy Malibu and warning lights went off on that car a lot! Not because I didn’t take care of my old Malibu, the car was a mechanical nightmare! When I described the problems I’d had with my malibu, other malibu owners reported similar issues with theirs. In the 8 years I owned that car, I had the get the intake manifold gasket replaced on it 3 times, the ignition switch on it went bad, the O2 sensor on it went bad, the alternator on it gave out before the original battery died and all of this happened before it hit 100k miles. When the engine on the malibu finally went caput, I sold it to Junk Dealer and then bought the Nissan. Time will tell if there’s been damage done to the Nissan because the shop messed up my oil change. I highly doubt any damage was done, but who can tell?
The questions remain though. Was there an oil trail into that parking spot and was the drain plug on the ground underneath?