Check Engine light cls350 08
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CLS350 CGI
Check Engine light cls350 08
Posted a thread earlier about some smaller problems which are now solved but instead I got some bigger ones. I have a 2008 CLS350 CGI with the 292 hp engine. I have had it for 3 weeks.
last sunday I got a check engine light just when I was about to park. I got the car diagnosed with a fairly simple app-connected thing and it said "P0171 - System too lean" The car runs just fine except maybe that it uses a lot of fuel, it has been using more fuel that I thought a 3.5 V6 would. I'm getting 13.0 liters /100km highway some times and 16 in the city... which is V8 SUV territory. And it takes some time to start on the first start of the day.
I am thinking of changing the battery as a first step because it seems bad anyway, after diagnosing the car it wouldn't start... just from standing with ignition for like 10-15 min. But I am hoping someone here may have some suggestions to where I should start if it continues... which it probably will
last sunday I got a check engine light just when I was about to park. I got the car diagnosed with a fairly simple app-connected thing and it said "P0171 - System too lean" The car runs just fine except maybe that it uses a lot of fuel, it has been using more fuel that I thought a 3.5 V6 would. I'm getting 13.0 liters /100km highway some times and 16 in the city... which is V8 SUV territory. And it takes some time to start on the first start of the day.
I am thinking of changing the battery as a first step because it seems bad anyway, after diagnosing the car it wouldn't start... just from standing with ignition for like 10-15 min. But I am hoping someone here may have some suggestions to where I should start if it continues... which it probably will
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Joined: Aug 2015
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From: DC Metro Area
2007 Mercedes E550
Posted a thread earlier about some smaller problems which are now solved but instead I got some bigger ones. I have a 2008 CLS350 CGI with the 292 hp engine. I have had it for 3 weeks.
last sunday I got a check engine light just when I was about to park. I got the car diagnosed with a fairly simple app-connected thing and it said "P0171 - System too lean" The car runs just fine except maybe that it uses a lot of fuel, it has been using more fuel that I thought a 3.5 V6 would. I'm getting 13.0 liters /100km highway some times and 16 in the city... which is V8 SUV territory. And it takes some time to start on the first start of the day.
I am thinking of changing the battery as a first step because it seems bad anyway, after diagnosing the car it wouldn't start... just from standing with ignition for like 10-15 min. But I am hoping someone here may have some suggestions to where I should start if it continues... which it probably will
last sunday I got a check engine light just when I was about to park. I got the car diagnosed with a fairly simple app-connected thing and it said "P0171 - System too lean" The car runs just fine except maybe that it uses a lot of fuel, it has been using more fuel that I thought a 3.5 V6 would. I'm getting 13.0 liters /100km highway some times and 16 in the city... which is V8 SUV territory. And it takes some time to start on the first start of the day.
I am thinking of changing the battery as a first step because it seems bad anyway, after diagnosing the car it wouldn't start... just from standing with ignition for like 10-15 min. But I am hoping someone here may have some suggestions to where I should start if it continues... which it probably will
You mentioned you have owned the car 3 weeks? The seller may have cleared the codes, knowing that the error was present, in order to sell the car. How much have you driven the car? It can take a few days of intense driving to go through the drive cycle to get the code to come back after clearing.
Believe me, p0171 is not the end of the world. It won't stop you from getting on the road. If you are a DIYer, this is the type of thing that you can save tons of cash fixing. But figuring out the problem will take time and diligence.
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CLS350 CGI
You have an air leak somewhere. This can be because a hose is not properly attached or an O2 sensor. This code will not do anything except reduce gas mileage and cause you to fail emissions.
You mentioned you have owned the car 3 weeks? The seller may have cleared the codes, knowing that the error was present, in order to sell the car. How much have you driven the car? It can take a few days of intense driving to go through the drive cycle to get the code to come back after clearing.
Believe me, p0171 is not the end of the world. It won't stop you from getting on the road. If you are a DIYer, this is the type of thing that you can save tons of cash fixing. But figuring out the problem will take time and diligence.
You mentioned you have owned the car 3 weeks? The seller may have cleared the codes, knowing that the error was present, in order to sell the car. How much have you driven the car? It can take a few days of intense driving to go through the drive cycle to get the code to come back after clearing.
Believe me, p0171 is not the end of the world. It won't stop you from getting on the road. If you are a DIYer, this is the type of thing that you can save tons of cash fixing. But figuring out the problem will take time and diligence.
Thats good news if it's the hose or O2 sensor then I guess. I am a sort of semi-DIY. If it's simple and not a great risk of messing something up I'll do it myself but I'm not very much of a mechanic. Where should I start?
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Joined: Aug 2015
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From: DC Metro Area
2007 Mercedes E550
Check your long term fuel trim to determine if there is a leak and bad fuel economy
You call also definitely know if you have a leak by using your OBDII scanner and looking at your "Long Term Fuel Trim (LTFT)". The LTFT is the aggregate of air or fuel added or removed to maintain your optimal air-fuel ratio.
Sounds complicated, but all it means is that if the number is much above 5, then there is a little leak, above 10, a medium leak, above 15 a big leak with a check engine light. Your car will keep running in all circumstances but fuel economy will suck and idle may be affected.
Feel free to private message if you need help!
MBWorld Fanatic!
Joined: Aug 2015
Posts: 1,059
Likes: 73
From: DC Metro Area
2007 Mercedes E550
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Joined: Oct 2017
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CLS350 CGI
OUTSTANDING that you found the leak. Sometimes those little leaks can be near impossible to find, even with a smoke machine.
You call also definitely know if you have a leak by using your OBDII scanner and looking at your "Long Term Fuel Trim (LTFT)". The LTFT is the aggregate of air or fuel added or removed to maintain your optimal air-fuel ratio.
Sounds complicated, but all it means is that if the number is much above 5, then there is a little leak, above 10, a medium leak, above 15 a big leak with a check engine light. Your car will keep running in all circumstances but fuel economy will suck and idle may be affected.
Feel free to private message if you need help!
You call also definitely know if you have a leak by using your OBDII scanner and looking at your "Long Term Fuel Trim (LTFT)". The LTFT is the aggregate of air or fuel added or removed to maintain your optimal air-fuel ratio.
Sounds complicated, but all it means is that if the number is much above 5, then there is a little leak, above 10, a medium leak, above 15 a big leak with a check engine light. Your car will keep running in all circumstances but fuel economy will suck and idle may be affected.
Feel free to private message if you need help!
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MBWorld Fanatic!
Joined: Aug 2015
Posts: 1,059
Likes: 73
From: DC Metro Area
2007 Mercedes E550
BUT surely old plugs could be the case.
If not, it is always good to change plugs
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