cdt not start

[johnnyb44]

Hmmm this sounds familiar. A few months back i had exactly the same problem as you. After towing my caravan to our destination i turned the car off. When i tried to restart it 10 minutes later it refused to start point blank. It turned over and it nearly caught a couple of times but it was having none of it. Ten minutes later it fired up first turn of the key as if nothing was wrong. It then did exactly the same thing again 3 weeks later. The problem was the cam sensor. Quick and easy to fit a new one but like everything else in this world well overpriced for what it is. I think Jules told me that it had also logged a fault code to.
I hope this is of some use to you.

[michael peters]

Originally Posted by john o

After the car had stood for an hour or so and cooled down it started and ran for an hour yesterday no problems which makes me think that it's a sensor breaking down but which one?

Had the same problem with my newly purchased 75 ctd tourer. Following advice from guys on this forum, did a leak back test which showed one injector leaking badly. Replaced it, problem solved.

[john o]

johnnyb44 how much was the cam sensor?

[chillyphil]

When the cam sensors go, usually they don't give a warning and don't show an error on the dash.

If it is an intermittent cam sensor fault, often just removing and cleaning them sorts it out.

[john o]

I'll clean the sensor and give it a try

[johnnyb44]

I think jules charged me around the 80 pound mark for the sensor. I think you can get them cheaper but they are not up to much. Fitting them really is a 5 minute job. After reading your post again ( properly this time though ) you say it cut out a few times on your journey. Im no expert but i don't think this would be cam sensor related. The cam sensor only plays a part when starting your engine and nothing else.
I may be wrong ( i usually am )

[john o]

when the engine cut out the under bonnet fuel pump stopped as the one in the tank has packed in I have a new in tank pump to go in this weekend

[Mike Noc]

If it is cutting out then that won't be anything to do with the cam sensor. The ECM only references the cam position sensor at start up, then ignores it until the next start sequence.

If it cuts out again with the LP pumps stopping then check the oil light comes on with key to position II when you try and restart it.

[chrissyboy]

On many engines with distributorless ignition systems and sequential fuel injection, a camshaft position sensor is used to keep the engine's control module informed about the position of the camshaft relative to the crankshaft. By monitoring cam position (which allows the control module to determine when the intake and exhaust valves are opening and closing), the control module can use the cam position sensor's input along with that from the crankshaft position sensor to determine which cylinder in the engine's firing sequence is approaching top dead center. This information is then used by the engine control module to synchronize the pulsing of sequential fuel injectors so they match the firing order of the engine. On some applications, input from the camshaft position sensor is also required for ignition timing.

[Mike Noc]

OP's car is a diesel though Chris so no ignition circuit to worry about. Once the ECM has checked the cam position from the sensor at start up it forgets all about it as the cams run at half engine speed and the ECM can count.

The injector timing on the M47R is taken from the crank sensor, which is a much more accurate way of determining piston position.












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