Fuel Trim Malfunction (Bank 1)

[dr1v3r]

hi guys anyone define this error for me please? also if asnyone knows how to fix the issue that info would be greatly appreciated also.

First things first thou. is this going to be expensive?

Also a mate was in car earlier and he said the jerking feel that i have feels like a loose mount of some sort, like engine mount or i think he said gearbox mount.

If anyone has any info on how to check any of these it would be great also.

and finally timing belts, are they hard to change and is it best to get a qualified tech to do it?

Cheers peeps.

Mick

[smoggy]

its something to do with your fuel mixture or Oxygen sensor
if you google Fuel Trim Malfunction (Bank 1) you get a number of hits

[dr1v3r]

thanx man will try google again

[rogerbagg]

This is a very common fault code - the code is normally P0170 it means that the fuel mixture is weak/rich on bank 1 (before the catalyst) this is normally caused by an intake air leak or sensor fault such as throttle position sensor or air mass meter. I cannot be caused by an O2 sensor as the O2 sensor has to be working for this fault code to appear as it works out a lean/rich mixture on bank 1 from the O2 sensor reading.

[rogerbagg]

If you let me know the make, model etc and the full P0### fault code I can tell you what the fault is likely to be.

[Dazza71]

Hi Guys,

I've just had a diagnostic on my 3.2 Vectra due to the emmisions light coming on. The results were the same P0170 fuel trim (bank not 1) - malfunction.

After an investigation one of my exhaust brackets had broken, this was fixed, ECU reset and touch wood the light hasn't come back on.

Check the simple things first, having loads of sensors just makes you worry its all gonna be expensive!! (£20 exhaust weld done.)