Engine Knocking and now won’t start

I have a 2005 Saturn Vue. Has a Chevy engine with around 100,000 miles on it although the car itself has 300,000. I’ve had it around 1.5 years. There was a knocking sound every once in awhile when I would start the car. Yesterday the knocking was very loud and I began to have trouble accelerating when the knocking was happening, which was not all the time. I remembered that I stopped for gas the other day and the station was out of everything except for premium gas. I had about 1/4 tank left at that point. Reading on some other sites, I thought this might be the cause of the knocking. I put regular gas in my car tonight after work. The knocking got a little worse and now my car will not start. Everything flashes and the car won’t turn over. It’s late and I live in an apartment so I don’t want to continue to try to start it and wake everyone up.

Any advice would be helpful.

Is the check engine light ‘ON’ ? What is the service history of your car?

Yes it has been for awhile. Every time I get it checked they tell me it’s my gas cap. Clear it and it stays off for awhile.

It sound to me like a fuel delivery problem.Was the fuel pump ever been replaced?A bad fuel pump can work erratically for a while until it stop fonctionning. When you turn your key to the run position,do you hear it priming?

Not that I am aware of no. I’ve had no issues with this car until now. I know the previous owners well. I can ask.

This model year has very few problems according to my source…carcomplaints.com. a few electrical issues,thats all.I wonder if you could tow it to an independant shop for diagnostic.This engine code could hide something else if the mechanic wasn’t careful.

the 1st motor lasted 200k miles. do you know why it was replaced? the 4cyl ecotec motors did have issues with timing chains. hard to say what is wrong with the motor now.

A shop didn’t do an oil change correctly and blew the engine. That’s why it was replaced originally.

Since January of last year regular oil changes, spark plugs were replaced last summer, new tires and brakes.

Replaced the spark plugs due to a 3 and 5 piston misfire code that cleared after spark plug replacement.

did you replace motor yourself? just asking for history. maybe you bought it with the 2nd motor installed. people like the vues. i see them for sale with bad motors so folks must fix them otherwise there would be no market to sell them

It started just fine this morning twice. And yes it sounds as though it’s priming okay. The knocking seems to be coming from the side of the engine the alternator and belts are on. I cannot see anything loose but that is what it sounds like. Almost a rattle instead of a knock. But like I said it’s intermittent. There’s no pattern to it.

I bought it with the 2nd motor in it. The car was originally bought brand new for a friends of mines bosses daughter. The boss owns a trucking company so the car has all of its maintenance done there with the mechanics. There was an oil change that they never put oil back into the car after and blew the engine. They replaced it with a Chevy engine. My friend bought the car a few years ago for her own daughter and now I have the car.

my kid has a v6 vue and i have owned several. never a 4 cyl. the early cvt trans on the 4cyl vues were bad. now the 04-07 vues w/4cyl have timing chain issues. not all but it quite common. if you hear a rattle in the serp belt side of motor than i would lean towards timing chain issues. you can call a shop and say 4 cyl ecotec/rattle and hear what they say.
might be splitting hairs but a knock is usually bottom end like a rod. a rattle is usually timing component bits. like the tensioner or chain

Have you raised the hood and actually bothered to check the motor oil level?

The issue has been resolved. Yes I bothered to check the oil, I’m not an idiot. It was my battery and tensioner.

BTW, premium gas will not cause ‘knocking’ in any engine.

Woohoo!!! Someone actually responded with update. Took 3 months though.

" Yes I bothered to check the oil, I’m not an idiot." Unfortunately on this forum this is an exception. Thank you for the update and solution though, this is also an exception.

Good luck,

Ed B.