Poor Fuel Economy after Spark Plug Change
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Joined: Nov 2014
Posts: 545
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From: Toronto & California
2015 ML400 4MATIC, 2016 C300 4MATIC, 2014 E350 4MATIC (Totaled), 2006 E350 (Sold)
Poor Fuel Economy after Spark Plug Change
Hi. Have a 2014 E350 with 124,000km and noticed an issue with the fuel economy after the spark plugs were changed. They were bosch spark plugs do not sure what is wrong. Any ideas? Thanks
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From: unbegrenzt
2017 GLE350 4MATIC
Are all the plug wires and coils properly connected?
Are you sure?
Who did the spark plug replacement?
Was a torque wrench used when the plugs were installed? Modern spark plugs need to be installed with the proper orientation for best performance, this is accomplished using a torque wrench.
Do you have a check engine light illuminated? Have the codes been read?
Are you sure?
Who did the spark plug replacement?
Was a torque wrench used when the plugs were installed? Modern spark plugs need to be installed with the proper orientation for best performance, this is accomplished using a torque wrench.
Do you have a check engine light illuminated? Have the codes been read?
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Joined: Jan 2009
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From: V E G A S
1922 Ford Model T / no OBD
How did the weather change in your area in last weeks.
I was still using my swimming pool 2 weeks ago, but now we have view of beautiful snow on mountains across the valley.
Lower temperatures will affect your mpg, especially on short commute.
I was still using my swimming pool 2 weeks ago, but now we have view of beautiful snow on mountains across the valley.
Lower temperatures will affect your mpg, especially on short commute.
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From: Southern US
2010 E550, 273 Engine: 2012 S550, 278 Engine
Is 2014 a direct injection engine? If it is I think the plugs need to be indexed so that the electrode points in correct direction inside the cylinder. This has to do with how well the spark can lit up the fuel mixture. If wrong plugs are used in DI engine they can cause loss of fuel mileage.
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Thread Starter
Super Member
Joined: Nov 2014
Posts: 545
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From: Toronto & California
2015 ML400 4MATIC, 2016 C300 4MATIC, 2014 E350 4MATIC (Totaled), 2006 E350 (Sold)
I changed it recently, about 2 weeks ago? Maybe it is the winter fuel. But I don't know if this is just me, but every time I start the car, I find the fuel gauge gets a bit lower
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1922 Ford Model T / no OBD
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From: Marin County,California
2016 E350 Sedan
Is 2014 a direct injection engine? If it is I think the plugs need to be indexed so that the electrode points in correct direction inside the cylinder. This has to do with how well the spark can lit up the fuel mixture. If wrong plugs are used in DI engine they can cause loss of fuel mileage.
