Fuel Trim Malfunction - Dealer keeps blaming air filter?
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Joined: Oct 2011
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From: New York City
08 C300 Sport
Fuel Trim Malfunction - Dealer keeps blaming air filter?
I have an '08 C300 with 49k. It is under warranty for the next two years.
For the last few months is has been idling badly. I have seen it rev itself to 1500rpm without me even touching the pedal. It threw a code (fuel trim malfunction) so I brought it in, and the dealer blamed an improper air filter installation. A 3rd party mechanic had in fact replaced the air filter so I just paid the $100 to the dealer for the fix and went on my way.
It is still idling bad, getting worse, and the code popped again. Brought it in and they blamed 'improper air filter installation' again and are trying to charge me money, again, even though the air filter hasn't been touched. What's up with these people?
For the last few months is has been idling badly. I have seen it rev itself to 1500rpm without me even touching the pedal. It threw a code (fuel trim malfunction) so I brought it in, and the dealer blamed an improper air filter installation. A 3rd party mechanic had in fact replaced the air filter so I just paid the $100 to the dealer for the fix and went on my way.
It is still idling bad, getting worse, and the code popped again. Brought it in and they blamed 'improper air filter installation' again and are trying to charge me money, again, even though the air filter hasn't been touched. What's up with these people?
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
It's either a bad MAF or the dealer is correct. The M272 gives trouble now and again with airbox fit over the MAF. Make sure that the airbox/filter is firm down over the MAF.
