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5th cylinder not firing

Mechanic found 5th cylinder not firing:mechanic charged me $125 to figure this out with a compression test. Now mechanic wants to remove head to see if (engine cracked?) estimated cost to fix $1000. Does this sound right? What are the pros and cons of this action? Thank You. Respectfully, Ann

Comments

  • Well. . .you've not told us any of the symptoms, or even what kind of car we're dealing with. So, we can't really have any idea at this point. Can you post more details?
  • Hmm,
    Need more info. But it is unlikely to be a fix for 1000$. He should not have said that. A crack or bad valve in the cylinder head maybe. Not the block though. Why did you go to the mechanic to start with? What car is this and how many miles?
  • Audi 5 cylinder???

  • Could also be a Vigor, assuming it's a 5-cyl engine. I figure it's a 6 or an 8 and we're talking about #5.
  • edited May 2012
    A lot of Volvo's run 5 cylinder engines. $1000 is cheap if it is a Volvo.

    The shop likely spent some time hooking up diagnostic equipment to test fuel, ignition, and when those checked out they did a compression check, likely on at least a few cylinders and likely all 5 to see how each cylinder reads. All that might take a hour so the $125 seems OK to me.

    The $1,000 is to find out the "why" of you have no or low compression in cylinder 5. Could be a burnt valve, some broken part in the valve train (what makes the valves move), a bent valve, a cracked head, or cracked engine block. Some of these are not too bad to repair and others might not be repairable at all. The $1000 isn't the end of the story.

    Did this motor overheat? Did the timing belt break?
  • When you come back to provide more info please report the specific compression numbers that were found for each cylinder and whatever error codes were found in the computer (format: "P1234")
This discussion has been closed.