A few questions

I have a 2000 Mercury Cougar with about 145k miles.

Today I was driving and when I slowed down to come to a stop it acted as if it wanted to cut off by sputtering. As I got down to about 5-10mph the engine shut off (the radio and everything else was still running) I noticed that as I was slowing down right before it shut off, the RPM was going very low, almost down to zero.

I do have check engine, and low coolant level lights on.
For the check engine there are a few codes.

  1. Something with the catalytic convertor
  2. 02 Sensors
  3. Transmission slippage
  4. I think there was something else but I forgot.

I do need new motor mounts.

The oil light comes only when I am idle and after driving for a good 5-10min. I changed my oil about a month and a half ago though.
The only time there is issues is upon stopping. Driving and acceleration is fine.

What do you suggest?


You really need to check that oil pressure with a mechanical gauge

If the oil pressure isn’t high enough, your engine is on borrowed time


Any shop will check it for free? Like Pep boys?
And why would it only happen when I stop?

Could be something simple, but from what you say this engine may just be nearing the end of its useful life and need rebuilding or replacment. hmmm … to start out, I think I’d probably do a compression check after-- like dB above says – the oil pressure test.


Autozone, Pep Boys will most likely read your codes for free

However, they will NOT check your oil pressure for free

But, as we’ve said, the oil pressure measurement has absolute priority

BTW . . . what kind of driving do you do? Short trips? How long between oil changes? How many miles between oil changes? Do you check your oil level at least every few weeks? What viscosity are you using?


I drive monday-thursday about 15min to and from my college. And then friday-sunday about 15min to and from work. Occasionally I may go to stores and friends house…but no more than 20-30min drives to the location.
I bought this car from someone I believe it was september sometime. I got the oil changed in october.


Thanks for the info

You’ve only had the car 3 months?

Did you know this person?

Were any of these problems present when you bought the car?

Is there any chance that the seller knowingly “passed the buck” . . . ?

As I said before, get that oil pressure measured ASAP


I bought it with the check engine on.
The codes were:

  1. A Leak (I got it fixed)
  2. Catalytic convertor
  3. Tranmission slippage

The oil light didn’t come on when I got it…it started happening about a month after.

I didn’t know her personally, but I don’t think she would scam me. She contacted me a couple times after I bought the car to see if it was doing okay.

So where do I go to get it checked? And how much should I pay?

Other than agreeing about checking the oil pressure I might add this.

It could be that the oil light is flickering on due to the idle RPMs dropping too low. Maybe the idle is dropping too low because of a possible vacuum leak or Idle Air Control valve issue.
A vacuum leak could also possibly cause some of those codes you’re referring to.

Depending upon the results of the oil pressure test and considering the 145k miles on the car, maybe the weight of the engine oil needs to be stepped up to something a bit heavier if O or 5W was used during the oil change.


I bought carb cleaner and sprayed around for a vacuum leak. I didn’t find anything. But maybe I missed it.


So the light was on when you bought the car. Okay

Did you know what the codes were when you bought the car?

Pretty much any shop will be able to do an oil pressure test.

I would guess about 1 hour labor, so maybe $100


Yes I met up with the lady at autozone before I bought the car to get the codes tested.

So the test is going to tell me what exactly?

I’m not a fan of using aerosols for vacuum leak checks although it can work to some extent. My preference is the use of a vacuum gauge.

I do not know how the vacuum system on a 2000 Cougar is laid out but I would strongly imagine that there are vacuum pods inside the dash that control some functions of the climate controls along with the possibility of a leak inside of the power brake booster. A gauge can easily determine if a leak exists in one of those out of sight places.


Is this something done at a shop?

The test is going to tell the mechanic if your engine has acceptable oil pressure


But it won’t tell what needs to be fixed in the event that the oil pressure isn’t acceptable?



Why not pay that same amount of money and have them check and see exactly what’s wrong…there was a place I knew that inspected for around $100.

A vacuum test can be done easily by any shop or DIYer but at this point I would agree with others about having the oil pressure test done first.

If the oil pressure is too low then the causes for that could be:
Worn crankshaft bearings.
Sludged oil pickup screen and/or oil galleys.
Worn camshaft saddles on the cylinder head.
Or all of the above.