How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Jerry Newton Your Own Question
Jerry Newton
Jerry Newton, GMC Technician
Category: GM
Satisfied Customers: 4508
Experience:  ASE Master Technician, L1, Master GM Technician. Over 20 years of bumper to bumper GM experience.
Type Your GM Question Here...
Jerry Newton is online now
A new question is answered every 9 seconds

2008 gmc acadia, # 1 cylinder misfire; exhaust valves not

Customer Question

2008 gmc acadia, # ***** cylinder misfire; exhaust valves not sealing and seat is damaged. what is the cause.
Submitted: 1 year ago.
Category: GM
Expert:  Jerry Newton replied 1 year ago.

This can be due to debris entering the engine and damaging a valve. This is unlikely unless you've had some engine work done recently, however.

Sometimes the valves just crack and little pieces break off, and this will damage the seat. Many times, there is no cause that a technician can identify, even if there was debris that caused it, that debris is typically long gone by the time the tech gets to it.