I have an intermitent noise on engine start up that I am looking for suggestions or theories.
To me when it makes the noise it sounds like no oil or very low oil. When the engine is turned off while making the noise sometimes the engine stops normal and outer times it diesels a little bit.

The car is a 2001 coupe with 157,800 miles on it. I beleve the engine to be completely stock. ( O K there is an oil catch can on it). The oil was changed 2,145 miles ago on 3-11-23. We bought the car in 2010 with 72,000 miles on it.

The first time I started the car today it made the bad noise. I checked the oil level, thought it was O K but I put in ½ quart. Started the car and it was quiet. Added the outher ½ quart, started the car and it was noisy.

I hope I am attaching a file with 3 engine starts. The video was made after the oil was added.

1st start noisy with normal stop

2nd start noisy with diesel stop

3rd start normal start and stop

I have started the car 10 times after the video, all normal starts and stops.

The 11th start was bad, The 12th start was good.

 

@twostepdon video appears to be set to private right now.
Edit: Fixed now

 

Thanks for telling me. Today is my first day on youtube. I will try to fix it.

 

Remove the main accessory drive belt and spin each accessory by hand. Maybe a water pump bearing or power steering pump bearing is making noise. Check for shaft play on each. Make sure the AC is off first.

 

I agree, pull the belt and try a few starts. Seems likely to be something belt driven.
https://www.harborfreight.com/mechan...ope-63691.html
A mechanic's stethoscope is cheap and can help pinpoint noises.

 

Had the problem repeat a few times but not a consistent fail. About Feb 19 2024 it gave me a consistent failure. (luckily in my garage) It gave me 3 bad starts that sounded like it had bean running without oil for 2 minutes. I took off the main serpentine belt and it gave me 2 bad starts. A friend told me to use the belt like a strap wrench on the harmonic balancer, pull hard left, make a mark and then pull hard right. I got about 3.5 inches of travel. At this time I am convinced I have a bad timing chain or a completely trashed engine. I had it towed to a local shop. It took about 5 days for them to get to it. The first thing they did was crank it up and it ran great. The only thing they thought could be a problem was a very small click when spinning the alternator pulley. It now has a new alternator and ran great for 2 weeks. (I kept the old alternator) It gave me 1 bad start 5 days ago but has run perfect since.

I think the timing chain and engine are solid and the problem is in the Powertrain Control Module or an input to it.

Of course I am looking for suggestions. If it gives me a consistent fail I do have a Tech 2 clone but I am not wiling to run the engine in a fail state for 5 minutes while I tell it I am working on a chevy corvette and I want to see the camshaft sensor.

Right now I think my best option is to replace the PCM

 

Kinda sounds like a starter staying engaged. The second shut off you can hear the starter still engaged. If the person turning the switch off did normally and fully, then something is allowing the starter to stay engaged. Starter, relay, switch, any one or combination. Or something I am not familiar with in the system.

 

That is something I had not considered, thanks.