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Just changed spark plugs and coils still not right under…

Customer Question
Just changed spark plugs...

Just changed spark plugs and coils still not right under load not firing under load.

Mechanic's Assistant: How many miles are on the car? When did you last change the plugs?

Plugs changed at 1000,300kl, Bosch double platinum along with coils.

Mechanic's Assistant: What is the model/year of your Mercedes?

S500 2008 Mercedes Benz four speed sedan.

Mechanic's Assistant: What year is your Sedan?

2008

Mechanic's Assistant: Are you fixing your Sedan yourself? What have you tried so far?

Yes, all I have done is replace coils and plugs new.

Mechanic's Assistant: Anything else you want the mechanic to know before I connect you?

Was running rough, changed coils and plugs with new parts,still running roug. Diagnostic reading missing number one cyldender.

Submitted: 1 year ago.Category: Mercedes
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Answered in 1 hour by:
8/5/2017
Mercedes Mechanic: FIXITMAN, Master Technician replied 1 year ago
FIXITMAN
FIXITMAN, Master Technician
Category: Mercedes
Satisfied Customers: 17,611
Experience: ASE MASTER CERTIFIED, AA DEGREE DIESEL/AUTOMOTIVE
Verified

Hello, my name is***** you are still getting a misfire on that cylinder then you need to do a compression test. This would tell you if there are any issues within the engine. If the compression is not within a few psi of the other cylinders then you have an internal engine problem. If not then it may have a bad fuel injector. I hope this helps. Please let me know if you need more help.

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