P0170 Fuel Trim Bank 1
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From: Southern NJ
CLK 430
P0170 Fuel Trim Bank 1
(MOVED OVER FROM W208 forum)
I just finished 8 hour brake job due to (4) very stuck rotors and I am beat. MIL has been on for several days and code reader indicates error code P 0170 - Fuel Trim Bank 1. [EDIT: Also P0173 sometimes] Wondering if it is more likely that it is MAF than an O2 sensor (?) Unfortunately I didn't spring for the better scanner so I don't have O2 readings.
BTW - I have been guilty of filling up the tank with the motor running but I have reset the error code 3x since then. I doubt it is just the gas cap.
I just finished 8 hour brake job due to (4) very stuck rotors and I am beat. MIL has been on for several days and code reader indicates error code P 0170 - Fuel Trim Bank 1. [EDIT: Also P0173 sometimes] Wondering if it is more likely that it is MAF than an O2 sensor (?) Unfortunately I didn't spring for the better scanner so I don't have O2 readings.
BTW - I have been guilty of filling up the tank with the motor running but I have reset the error code 3x since then. I doubt it is just the gas cap.
Last edited by Freddie; Mar 21, 2005 at 07:39 PM.
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PO170/173 are self adaptation codes. Generally you have either a "part load" fault or an "idle speed" fault. The part load is more common and generally caused by a MAF sensor. The idle speed fault is usually caused by a vacuum leak. Make sure you check the entire intake tube for signs of air leaks before you replace anything. Also make sure the air filter is clean and there isn't alot of dirt in the bottom of the airbox-this can cause "sandblasting" of the MAF sensor if it gets past the filter.
