I was on my way to work while driving up a hill. Going around a turn my engine and car jolts and I pull over. My car is making a terrible noise. It's running very rough and has 3x more vibration as usual. Which is a considerable amount. I suspected it's was a jumped timing. But most likely isn't because it still runs. It's a knocking sound but isn't consistent with rod knock. Turns out the car was very low on oil and I put oil in the car as well as spark plugs. It still knocks and runs very rough. Any help is appreciated.

 

Year of car and engine type, 4-cylinder or V-6?

How low on oil was the engine?

Did the oil pressure light ever come on?

Is the check engine light on?

Did the coolant temp gauge get into the red?

 

its a 95 4 cylinder, it seemed pretty low on oil and now it seems to have a leak perhaps. There is no oil pressure gauge and it runs totally fine for how long we were running it temp wise. Check engine light is not on.

 

The engine holds about 4.5 quarts of oil. It can run on a quart less fine, 2 quarts less OK below this who knows. That's why asking how low the on oil was. How much oil did you add to bring the level back to the top of dip stick.

Did oil pressure light ever come on or start to flicker?

What does "it runs totally fine for how long we were running it temp wise" mean?

The oil pump seal can start to leak resulting in a pretty rapid loss of oil. The oil would be coming out the firewall side of the timing belt cover below where the half round side extension of the cover is located. The flow would be small but steady when the engine was running.

Use a section of hose as a stethoscope to narrow down the area of knocking.

 

We were only running it a for a minute or two at a time and the temp stayed steady and wasn't in danger of over heating. The oil was brought up to 2/3 of the dipstick after we put 3 quarts of oil. Knocking seems to be deep in the bottom end. Mostly likely a toasted bearing which is the opinion I've been getting a lot. Just wanna make for damn sure. If it's not the bearing and is the oil pump seal what would that meaning in terms of repair and cost

 

Temp may not be an issue. The lack of oil may have damaged a bearing. A bad oil pump seal would just leak oil, not make noise or effect engine operation unless the engine ran out of oil.

The engine has two balance shafts mounted on a cradle below the crankshaft. This might dampen the noise.

Try running the engine then disconnecting one ign wire at time. This will lessen that cylinders load and with this possibly the knocking which can then be linked to a specific cylinder.

If a bearing it will decrease noise with decreased load.