Citroen C4GP 2L petrol fault codes

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Citroen C4GP 2L petrol fault codes

Post by Craigie »

I have a 2007 C4GP 2L petrol 78000 miles.
Having a recurring fault code which happens intermittently with no difference in driving. Occasionally when idling there's a bit of hunting/chugging but very occasionally
Fault codes are P0170 and P0172
Could these be the coil pack or something else? Any help would be appreciated

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Re: Citroen C4GP 2L petrol fault codes

Post by GiveMeABreak »

Those errors relate to the fuel injection.

P0170: Mixture regulation: Coherence. Basically the fuel trim is out - in this case too rich - see the other fault below:

P0172: Mixture regulation: High stop. The fuel trim is too high. The engine ECU reads parameters and data to adjust the fuel trim which includes the MAF / MAP / Oxygen Sensors to measure exhaust gasses.

So in this case the mixture is too fuel rich with not enough oxygen.

Common culprits could be in no particular order: Oxygen sensor, fuel regulator, worn plugs, a dirty MAF sensor.