Hi all,

Sorry for the newbie post. I have searched high and low for some pointers here, I promise!

My 04 plate Focus Mk1 1.6 petrol has an annoying intermittent fault. Basically the MIL indicator (engine fault) light comes on about once a week, I've scanned and cleared it about 10 times now, and it's always the same code: P0340 - camshaft position sensor fault. Now I'm not convinced that there is a proper fault with the sensor, the car's driving behaviour is totally unaffected, no stutters etc. It only ever happens when i'm crawling along in heavy traffic - the freeze frame data usually shows a speed of 1 to 5 MPH, all other parameters look normal. As it happens at slow speeds it's unlikely to be vibration causing a loose connection to misread the sensor value (it's NEVER occurred at a faster speed).

Any ideas what could be causing this, and with being intermittent how I could diagnose?

I was going to leave it, but i'm thinking about selling the car - can't really do it with a warning light on!

Cheers

Lee

Hi all,

Sorry for the newbie post. I have searched high and low for some pointers here, I promise!

My 04 plate Focus Mk1 1.6 petrol has an annoying intermittent fault. Basically the MIL indicator (engine fault) light comes on about once a week, I've scanned and cleared it about 10 times now, and it's always the same code: P0340 - camshaft position sensor fault. Now I'm not convinced that there is a proper fault with the sensor, the car's driving behaviour is totally unaffected, no stutters etc. It only ever happens when i'm crawling along in heavy traffic - the freeze frame data usually shows a speed of 1 to 5 MPH, all other parameters look normal. As it happens at slow speeds it's unlikely to be vibration causing a loose connection to misread the sensor value (it's NEVER occurred at a faster speed).

Any ideas what could be causing this, and with being intermittent how I could diagnose?

I was going to leave it, but i'm thinking about selling the car - can't really do it with a warning light on!

Cheers

Lee

this is for the 1.8 diesel but might help

ord Focus and Mondeo 1.8 2.0 TDCi 2000 - 2003

Problem: Engine hard to start, lack of power, rough idling etc.

Solution: A common problem has been identified with the above models and an insufficient signal from the camshaft postion sensor (CPS). The fault code P0340 may have been triggered which relates to the CPS. A revised wiring harness / sensor should be installed which increases the sensor signal from 5 volts to 12 volts. The increase in voltage will provide an improved signal from the sensor.

like it says it could be the harness or the signal or the sensor only changing it will show itf it is or not

Hi,

Just in case it's a help to anyone else, i've solved this problem for free.. I unbolted the camshaft position sensor, cleaned it including the contacts with switch cleaner then refitted. It's been nearly 3 weeks since, and no engine light.

Worth a try before paying to replace the sensor.

Cheers

Lee