Guys,

I'm having a problem with the engine management light in my wife's Mk2 Fabia. It's a 57 model, BBM engine, 105,000 miles on it. Full service history, generally very reliable.

Last week it produced a check engine light so I read the codes and it came back with a P0341 Camshaft Sensor error. I cleared the code but it was back within a day or so.

I bought a new camshaft position sensor and swapped it in, and reset the engine light. All was well, but the code and light were back again a couple of days later (i.e today), plus reports of the car 'not running right'.

I've just cleared the code and taken it for a drive. Code and light are back almost immediately, and the car definitely isn't right; it's lumpy to drive, slow to start (it usually starts very crisply) and seems down on power.

Clearing the code again and leaving the cam position sensor unplugged makes it still drive lumpily but the light stays off. (Yes, you read that right.) Plug the sensor in and the light comes on again.

I've swapped the sensor back for the old one and the light has stayed off for a bit so I'll see how things go. The huge snag is that the car is booked for an MOT tomorrow morning and an engine management light will make it fail. I'm therefore hoping that the light will stay off for long enough to pass the MOT.

If anyone has any wisdom then I'd love to hear it. FWIW, the P0341 code appears twice - once as 'active' and once as 'pending'. Clearing them both makes the light go off. I've checked the wiring to the camshaft position sensor and it doesn't seem damaged (rubbed/frayed/snapped).

I think the key question is whether I have one problem or two - i.e is the lumpy running related to the light? It could be a separate thing, and the lumpy running being caused by a failing coil pack (for instance), or they could be the same problem with different symptoms. Logic would suggest the latter, but they light/code appeared a good few days before the lumpy running. It could be a coincidence but it has been VERY hot this week so the lumpy running could be fuel vaporisation in the lines, perhaps?

Any thoughts, suggestions or otherwise please let me know. Thanks.

Might be the timing thats slightly out. Not sure if its a chain or belt on yours but if its jumped a tooth it would explain the poor running unless the new sensor is either not working or compatible? Another option according to rosstech vcds is that low oil or oil pressure can also ping up the same code?

copied from rostech

Possible Symptoms

• Malfunction Indicator Light (MIL) active

Possible Causes

• Wiring from/to Camshaft Position Sensor (G40) faulty

• Camshaft Position Sensor (G40) faulty

• Timing misaligned

• Low level oil or low oil pressure

Possible Solutions

• Check Wiring from/to Camshaft Position Sensor (G40)

• Check Camshaft Position Sensor (G40)

• Check Timing

• Check Oil level and/or Oil pressure

Alasdair

Edited 22 June22 Jun by Alasdair1
added further info