Diagnostic Trouble Codes P0104, P1351 following antipollution fault warning.

Originally started to receive an fault antipollution warning with an flashing orange engine auto-diagnosis system light. I initially tried JLM DPF cleaning fluid. Though not with a full tank of diesel without success. The engine auto-diagnosis system light is now permanent. I am not experiencing any driving problems. However would like like to rectify the fault. A cheap (non lexia) OBD2 scanner has diagnosed P0104 Mass or Volume Air Flow Circuit Intermittent and also P1351. Both was cleared by the OBD2 but returned after approximately a couple of journeys. I have inspected the MAF and it did not looked visibly dirty. However following a good clean with Archoil MAF Cleaner the problem still persists. Is it best to start again and use lexia diagnostic tool or try JLM cleaning fluid with a full tank of diesel or just go ahead and replace the MAF? The vehicle has just done over 100,000 miles. It is principally used by my wife for short journeys 10-20 miles twice daily and she only ever fills the tank generally to half full.

Hi mwalindo

P1351 is the pre-heat really fault. This powers the glow plugs and faulty glow plugs can take out the relay. P1351 is very common on the early C3 diesels and often gives no symptoms for starting or driving. Changing the glow plugs and the relay can be very difficult so it's often not worth doing.

But I am not sure how important (anti-pollution fault wise) they are for the later 1.6 DPF models.


P0104 is a MAF fault. The test for a MAF Ilis to disconnect it and go for a test drive. If the car drives better with the Mass AirFlow sensor disconnected then the MAF is faulty.

If the car drives better with the MAF connected then the MAF is good and changing it won't help.

Cleaning the MAF is a good thing but probably won't fix an intermittent fault because dirt build up is permanent (until it's cleaned)

Using the JLM on a DPF equipped C3 won't do any harm and if the journeys are short or low speed then it would be beneficial to force a regeneration of the DPF/FAP.

My next step would be to use lexia to see if there are any missing codes (related to the anti pollution fault), look at live data from the MAF and anything else suggested by lexia.

But, an intermittent fault is going to be difficult to pinpoint quickly.