Low compression

Tiny
KORY DORSAINVIL
  • MEMBER
  • 2010 DODGE
  • 3.5L
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 93,000 MILES
I have low compression in a single piston in my car and so the engine light has come up in my car, under a code scanner it is a misfire. A bit of history on the car the Carfax stated that the car had water damage and it was taken off the road before being reinstated I do not know if that will help, but I just wanted to know what you would suggest as the first step I should take to resolve this other then an entirely new engine. Or if there could be a specific item I should attempt to replace to see if it resolves the misfire.
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Wednesday, April 19th, 2017 AT 9:15 PM

6 Replies

Tiny
CARADIODOC
  • EXPERT
You need to list which model you have. Also, please list the exact fault code number. The place to start with misfire codes is usually spark plugs and wires. At the mileage you listed, those are the best suspect.
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Wednesday, April 19th, 2017 AT 9:51 PM
Tiny
KORY DORSAINVIL
  • MEMBER
It is an SE and I checked the spark plugs they had rust on them and I forget the exact code but it affected piston two.
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Thursday, April 20th, 2017 AT 5:40 PM
Tiny
CARADIODOC
  • EXPERT
Based on the mileage, we would replace the spark plugs and wires without wasting time testing or inspecting them. It is only after that, in the unlikely event the problem is not solved, that we would spend our customer's money on the time needed to dig deeper. If you do not want to start with that, or if those parts were replaced recently, switch the spark plug from cylinder two with one of the others, erase the fault code, then drive the vehicle to see if a new fault code sets for the cylinder you moved the suspect spark plug to. You can do that with a third cylinder for the wire, and even another cylinder for the injector. Moving parts to different cylinders can be an effective way to find a part with an intermittent problem.

You have not listed a model yet. I do not know if you have a truck, a minivan, SUV, or a car.
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Thursday, April 20th, 2017 AT 5:53 PM
Tiny
KORY DORSAINVIL
  • MEMBER
It's a 2010 Dodge charger SE V6 3.5L with 93,000 miles
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Friday, April 21st, 2017 AT 3:41 AM
Tiny
SATURNTECH9
  • EXPERT
Did you do a compression test if so what were the readings?
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Friday, April 21st, 2017 AT 12:39 PM
Tiny
STEVE W.
  • EXPERT
If you have low compression and the plugs had rust on them I would get a bore scope and look inside the cylinder to see if the cylinder has any rust pitting or roughness or damage. Then run a leak down test. That will give you an idea if the compression loss is due to the valves (could have rust on a valve stem holding a valve partly open) or due to the piston rings. It's possible that the engine was running and it took in enough water to hydro-lock that cylinder and it bent the connecting rod or did other damage. Just need to test and eliminate the possible issues.
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Saturday, April 22nd, 2017 AT 1:50 AM

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