P2086 code and P0171 on my 05 ml350
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From: Westcoast/Interior
02w163ML500 / 97w210E50AMG / 99w202C230k / 95w124500e-wip
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From: Waldorf, Maryland
‘05 ML350 and ‘05 CLK 320
P0171 System too lean at Bank 1 DTC P2086 P0170.
It smokes a little and while idling it will cut off. Check engine light comes on. Diagnostic reveal a code P0171 System too lean at Bank 1
DTC P2086 P0170.
DTC P2086 P0170.
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Joined: Nov 2015
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From: Westcoast/Interior
02w163ML500 / 97w210E50AMG / 99w202C230k / 95w124500e-wip
Simpliest checks first....
I'd first check for any vacuum leaks somewhere under the hood, maybe on the backside.
Also there are other things that can cause a lean condition, ie. clogged fuel filter, faulty injector, faulty injector O-ring, low fuel pressure, dirty MAF Sensor.
MBWorld Fanatic!
Joined: Nov 2015
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From: Westcoast/Interior
02w163ML500 / 97w210E50AMG / 99w202C230k / 95w124500e-wip
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From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
If you have both codes stored, then in all probability you have a large intake air leak at the intake tube.
When you replaced the MAF Sensor, did you remove the air intake tbe? If so, check to see if the clip is broken, Feel under the tube.
Understand that when there is an air intake leak, the ECM will add more gas via the injectors to compensate for the added air. But if the leak is very large, the ECM will only adjust the gas to a certain point and then the codes are stored.
When you replaced the MAF Sensor, did you remove the air intake tbe? If so, check to see if the clip is broken, Feel under the tube.
Understand that when there is an air intake leak, the ECM will add more gas via the injectors to compensate for the added air. But if the leak is very large, the ECM will only adjust the gas to a certain point and then the codes are stored.
Last edited by Maj. Dundee; Jun 8, 2019 at 03:59 AM.
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From: Waldorf, Maryland
‘05 ML350 and ‘05 CLK 320
The hose to from the manifold to the engine was completely off and replaced. The check engine light went off. Now its idling too high and cuts off.
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From: Bronx, N.Y.
2002 ML 320 & 2006 ML500
Thread Starter
Junior Member
Joined: Nov 2018
Posts: 18
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From: Waldorf, Maryland
‘05 ML350 and ‘05 CLK 320
It was the one with the circle. As we went to erase the code, the check engine light automatically went off. But when I start the engine it idles high and cuts off but the Check Engine Light isn't on now:
