2001 C240 "CEL"
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Newbie
Joined: Nov 2008
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2001 C-240
2001 C240 Check Engine Light
Hey guys, I'm new to this site and the owner a beautiful "old" New Car. I got this car from my mother (don't worry I paid her a fair price...much more than trade in) with only 16,000 miles (not missing any zeros). Anyway, got the darn CELlight and did some basic research. Autozone, pulled the codes for free and the only one was P0173. aka "Fuel Trim Bank Two" and NOT the more usual combo (P0170&P0173). The car runs great from start to idle to WFO. Ideas? thanks. p.s. What a GREAT site!
light and did some basic research. Autozone, pulled the codes for free and the only one was P0173. aka "Fuel Trim Bank Two" and NOT the more usual combo (P0170&P0173). The car runs great from start to idle to WFO. Ideas? thanks. p.s. What a GREAT site!
Last edited by smak161; Nov 15, 2008 at 12:24 PM.
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Joined: Nov 2001
Posts: 5,851
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From: Huntington Beach, Ca.
'17 Jaguar XF
Try cleaning the MAF. You should also STFF for another gazillion things to do 
There's a sticky on the TBs for your car that's a mile long as well. If you go to the dealer and ask them to pull up your car's history they can tell you which ones haven't been done yet.
There's a sticky on the TBs for your car that's a mile long as well. If you go to the dealer and ask them to pull up your car's history they can tell you which ones haven't been done yet.
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Joined: Nov 2008
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2001 C-240
Not the MAF
Sorry it took so long to get back to the forum...I work out of town. Anyway I was all set to clean the MAF last Sunday and install 2 new STP air filters...But the idea of only one code (P0173) on "bank 2" was still bothering me. When I disassembled down to the MAF in hand I decided to check as much of the vacuum system as I could. I found the main vacuum line for the brake booster was cracked at the 90 degree elbow to the intake. This line is the one that goes up and over the electrical connection to the MAF, then down under the throttle body, then back up and across to the brake system in front of the driver. I ordered the part from MB...$110 dollars, since the hose comes complete, along with a new "O" ring and connector/pressure fitting for the intake end $18, on the dealer's advice. Just installed last night...runs perfect...NO check engine light. Surprisingly we had no brake symptoms, but there is an alternate source of vacuum to this booster line that connects to the main vacuum line very close to the throttle body (it all comes with the $110 part, complete). One final note...the car, since I have had it (2 months) has always had a bit of a "dead zone" in the throttle...hesitation on hard acceleration...my mother said this had been there for a while and had even complained about same to her MB dealer...they told her she just didn't drive it hard or often enough
! This symptom is now gone! Anyway, I suspect the Check Engine Light, shortly after we got the car...it's my wife's daily driver now (and she is a notorious "lead foot") has everything to do with the trim air system obviously not being able to keep up with such a large vacuum leak, when driven like it should be. FUN car!!! Hope this helps somebody else.
! This symptom is now gone! Anyway, I suspect the Check Engine Light, shortly after we got the car...it's my wife's daily driver now (and she is a notorious "lead foot") has everything to do with the trim air system obviously not being able to keep up with such a large vacuum leak, when driven like it should be. FUN car!!! Hope this helps somebody else.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Just for good measure do a throttle reset - see DIY
