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2000 LeSabre really sucks

I left the engine running while I tried to add oil. There is so much suction that I had to really pull on it to get it off. Once it was off the engine died…is this normal?

I hope so. It would really make a mess if it blew the oil out of the oil filler hole!

I’d like to hear an explanation of exactly what it is that is so hard to pull off because of suction. Oil filler cap or what? Just wonderin’.

I’d like to hear an explanation of exactly what it is that is so hard to pull off because of suction.

I would like to hear why someone would try to add oil, or check the level with the engine running.

One thing at a time!

Either add oil to the engine or “pull on it” and “get it off”.
Doing both simultaneously is potentially very messy.

Perhaps the engine died from embarrassment over your public behavior.

(Sorry, the devil made me say this!}


Best post of the day, for sure!

I did not need to check the oil level. When the “low engine oil light” comes on, the vehicle is at least one quart low. I simply wanted to add a quart. The car had been sitting for a while and was difficult to start even with a jump, so I did not want to turn the engine off. Some engines, like Honda for example, have positive pressure in the crankcase and it would be very messy to add oil while the engine is running. Apparently the Buick has vacuum in the crankcase, possibly part of the emissions system. That vacuum made it very difficult to remove the oil filler cap and when I did that change in vacuum killed the engine.

I Can See What Causes Your Confusion.

My car’s owner’s manual advises to check the engine oil after turning off the engine, but fails to mention turning it off when describing adding it. The manual should state “Turn off the engine before adding oil”. Was it just intuitive to fire it up before adding any oil?

By the way, my manual says nothing about shutting off the engine before changing the oil, battery, spark plugs, or belts, but it should definitely be done for simplifying the prodeures and for safety reasons. I can’t answer your question pertaining to the death of your engine as that isn’t in my manual, either. I guess they thought that would just be intuitive, too. Sorry.

My guess is you may have a stuck open PCV valve, that could cause excessive crankcase suction. But the good news is its a $2 part a your local auto parts store.

Is what normal? Is the engine dieing normal because you removed the oil filler cap? That action isn’t taken into account when the car makers’ engineers design the engine management systems. If it were, they may as well design into the system any other things which are “normally” done when the engine is off. Sure, some engines may continue to run when the oil cap is removed; but, so what?
You’ve known that you’ve had engine problems for a long time, you could have done some repairs before now, if you wished.
The engine management system runs on METERED air flow (thus, the various sensors). When that balance is suddenly unbalanced, WHAT should happen?
If you have a problem re-starting a warm engine, the engine really has problems.
I think that warning light is for LOW OIL PRESSURE (as low as 8 psi); not, oil low level. Of course, lack of oil causes low (or, NO) oil pressure.
Have you been checking the dip stick as well as going by the LOW OIL light?
Disconnect the electrical connector, on the oil pan, wipe it off, and reconnect. That may be all it needs to read correctly (IF it was incorrect, before).

I think Americar got this one. In addition to causing vacuum in the crankcase, the stuck PCV valve probably also allowed a surge of air to be drawn in past the point of the mass airflow sensor when the oil cap was removed creating improper metering, a sudden lean mix, and engine stalling.

I’m theorizing of course.

What could I have meant by “METERED air”? Something different?

I’m not disagreeing. I’m clarifying. And connecting the suction symptom with the stalling symptom.

No disrespect, but in your focus on adminishing the OP your post became somewhat rambling. As long as we’re all atempting to contribute to the solution there’s no point in getting overly defensive.

Have a great weekend.

You’re right. The OP won’t read a long response simply because it is long. I know, I waste my time.

keep it up, because you are technically exacting, which helps others reading the forum understand the whys and hows.

to the OP.

you mention the oil light. are you sure the check engine light isnt on too? it sounds like you may need to do some other maintenance, other than what the idiot light calls for.

by the way. you should NOT be depending on the oil light to let you know the level of oil in your engine. typically when the oil light comes one damage is already being done to your engine. you should be checking the oil at each (or every other) fill up. as another post said, low oil pressure is NOT indicative of low oil level. it MAY be low, or it may be a failing or clogged oil pump.

I’ve been guilty of using more words than i need too probably more often than should be the case. But it isn’t wasted time. As long as it’s focused on the issue at hand it all helps.

Thanks,it was the pcv valve.

I want to thank the OP for posting back what the problem turned out to be. So often we try to help and never hear if the problem was resolved.

It was good to hear back. Thanks.

I kind of figured a PCV was the issue and adding oil while the engine is running in combination with the bit about Hondas having positive crankcase pressure only raises the eyebrows higher.

Your welcome. : )