camshaft sensor

[Bluejj33]

Hello All,

My 57 octavia 1.9tdi 84k (mostly motorway miles) broke down yesterday , a loss of power and then refused to start. AA bloke diagnosis said a faulty camshaft sensor (2 scans by him) garage changed it today and it still will not start and still showing as the fault......no other symptoms at all (oil in water/water in oil) any ideas or advice very welcome. Thanks bluejj33

[Tech1e]

What's the fault code?

In theory a cam sensor shouldn't stop the engine from starting. Will take longer to start as the cam sensor is used for cylinder recognition.

[mannyo]

As Ross mentioned, with a duff cam sensor the engine should still start. When mine went on a Superb MK2 2.0PD it always started fine from cold but once warm it would take 20-30 seconds of cranking before it started. It never failed to start, just took a very long time and once running was perfectly fine.

Edited 29 January, 2016 by mannyo

[Bluejj33]

Thanks for the reply.....car back and running fine after changing the pulley....they had tried everything and as a last desperate resort changed the pulley. The lad who done it has worked on 100s of these and never ever seen it. I'm going to scan it after my tea, clear any errors and run it up the motorway a few junctions and re scan then compare.......it's all a bit bizarre but as long as it's fixed

[Bluejj33]

He said the sensor picks up its readings off a plate on the pulley so I'm guessing it's made of alloy with a steel/magnet insert.....I'm no expert but it kept him busy all day !

[Tech1e]

I've seen a fair few of them plates fall off the back of the pulley. They are only friction welded (I think) in a couple of places.

[Bluejj33]

Error code was as follows:

012296 - Camshaft Position Sensor (G40)

P3008 - 000 - signal out of range- intermittent

I've cleared the faults and give it a run and re scan gave no faults....and it's not started as well since I've had it so maybe a timing issue ?

Thanks again

[Bluejj33]

I've seen a fair few of them plates fall off the back of the pulley. They are only friction welded (I think) in a couple of places.

[Bluejj33]

I'm just hoping that's it sorted.....too bloody complicated these bloody cars ! LOL :-)

[Bluejj33]

I'm just hoping that's it sorted.....too bloody complicated these bloody cars ! LOL :-)

[Tech1e]

Error code was as follows:

012296 - Camshaft Position Sensor (G40)

P3008 - 000 - signal out of range- intermittent

I've cleared the faults and give it a run and re scan gave no faults....and it's not started as well since I've had it so maybe a timing issue ?

Thanks again

Yeah that fault code was not going to be the sensor. It's a mismatch between crank and camshaft signal.

[Bluejj33]

So it was the pulley causing the fault ?

[Tech1e]

So it was the pulley causing the fault ?

I would certainly think so.

[Bluejj33]

I have also noticed the fuel consumption appears to have dropped and with it being so eager to start would this surgest a timing issue ? I have a VAG cable but not sure what values to look for....any help would be greatly appreciated?

Cheers bluejj

[Tech1e]

VCDS/Engine Module/ block 4/ torsion value

Looking for about -0.5

[Bluejj33]

I've got -1.0°KW ?

[Bluejj33]

Just cruised up the motorway at 60mph for 15 miles and got a trip reading on 61mpg. Then ran it on my drive for no more than 10 minutes for vcds scan and the trip has dropped to 48mpg !! That can't be right....??

[Tech1e]

Why not? You are using fuel but not moving. So your MPG is going to alter.

The Torsion value is within limits, timing would be OK.

[Bluejj33]

It never used to do this as noticeably before the breakdown and this is the reason behind my concern. VCDS showing it's using 0.6 l/h on idle.......is this excessive?

[whitep]

0.6l/h is perfect

 

Your problem is beginning to sound like mine...... but wrong engine!

[Bluejj33]

I'm wondering if I should try the old disconnect the battery for 2 hrs and then leave on tick over for 10 mins to reset the sensors and throttle potentiometer.....I've just read a thread saying the ecu can learn the way you drive so with the garage having it all day last Friday it might have been reset and the engine run up over/above idle speeds to get it started. Or am I just clutching at straws ?? LOL

[Tech1e]

You don't have a throttle potentiometer.

You can do a terminal 30 reset if you like, disconnect both battery terminals and connect the clamps together for a minute, that will do the same as disconnecting for a few hours. However any readiness codes and learned values are normally reset when the fault memory is cleared.

[Bluejj33]

Would doing this affect my re map ?

[Tech1e]

Would doing this affect my re map ?

No

[Bluejj33]

Thanks for the info .