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Amedee, Buick Mechanic
Category: Buick
Satisfied Customers: 26427
Experience:  ASE certified Technician advanced level specialist. Wisconsin certified emissions state inspector
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Buick Century Limited: I have a 2001 Buick Century, 3.1L engine,

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I have a 2001 Buick Century, 3.1L engine, 189,000 miles. Last week I was passing thru Live Oak, Florida, and was seeing
standing water from Tropical Storm Debbie still around. I made the mistake of trying to cross a road with water too deep
and stalled the engine. I pushed myself out to dry pavement and had to jump start the engine with the help of a samaritan.
Now the engine is running rough. I got back to Tallahassee, some 120 miles, and have been able to use the car, but it is
still missing and running poorly. The check engine light has been on for awhile due to a bad camshaft sensor, but it wasn't
running rough until I ran the car through foot deep water. Got any theories?

My name is XXXXX XXXXX I can assist you with your question.

Thanks for asking your question on Just Answer and I am sorry to hear about your vehicle troubles. I will try my best to point you in the right direction.

Off of the top of my head, it sounds like you have bad tune up parts or even a mechanical condition with the engine because of hydro lock condition caused by water getting sucked into the engine. Before we jump to any conclusions, the problem first needs to be diagnosed. From there we can apply a fix in order to resolve the issue.

Since the engine is misfiring, we need to figure out which cylinder or cylinders are misfiring. You can do this using an insulated pliers and removing the spark plug wires one at a time from the spark plugs while the engine is running to see which cylinder does NOT affect engine rpm when the wire is removed from the spark plug. Or the other way is to hook up a code reader to the diagnostic connector under the dash and read the computer codes. However, since you have a bad camshaft position sensor this could result in some misfire codes so it may not be that reliable. However, you could clear the codes and see which code comes back first. Chances are the computer will flag a code for the misfiring cylinder or cylinders and make it much easier to track down the problem.

You could scan it yourself or get it scanned by your local auto parts store for free.

Once we know which cylinder is misfiring, then we check spark fuel and compression on that specific cylinder and replace or fix the bad or broken part causing the engine to misfire.

I hope this helps! Please let me know if you have any further questions!
Amedee and other Buick Specialists are ready to help you
Customer: replied 5 years ago.
I was unable to test the plugs without moving the engine, so I took the
car to two local parts stores to read the codes and they didn't come up

with any misfire codes. I finally took the car to a shop, they found misfire

codes, diagnosed the problem as a coil pack and are replacing that and

the cam position sensor, then clearing the codes to see if some other

codes come back, like mass air sensor and catalytic converter. My feeling is that the cat convertor code was coming up because of the

misfire (it had never come up before). I will probably tell the shop not

to do anything more until I talk to you. It's a good shop, but I can't afford



Thanks for the heads up!

I think your headed in the right direction.

Did you have any further questions for me?
Customer: replied 5 years ago.
Soooo, $500 later, my Buick is still misfiring and idling roughly, just not
as badly as it was. Any clues as to where to go from here? Should I

go buy a coil pack and try it in the place of the packs which weren't

replaced? It doesn't look difficult to do. The miss was on the #2/#5


If the engine is still misfiring, you need to scan it for codes to see which cylinders are misfiring and then go after each specific cylinder and check for spark fuel and compression.

A compression check is a good thing to rule out first. Then the fuel system because it is easy and then go after the ignition system.