Car won’t start or starts hard with cam sensor

[Alexutz Preda]

Hi Guys

Please can anyone help with this issue ? Audi A4 2008 B8 2.0TDI engine. If I disconnect the camshaft sensor it will start after a longer crank, but will start at 1st attempt.

If I connect the camshaft sensor, the car will start and die immediately after 1 second. If I keep trying, it will eventually start after about 15 attempts....

Engine management light was on with these codes:

P2015 - Intake Manifold Runner Position Sensor

P0671, P0672, P0763, P0674 - Glow plugs

P0016 - Crankshaft Position-Camshaft Position Correlation Bank 1 Sensor 1

Mechanic suggested changing camshaft sensor, Glow plugs, timing belt and water pump, which I did.. but the problem still persists.

Now I only get P2015 code... the other codes are not coming on anymore... but the car still won’t start with camshaft sensor plugged in...

[OliNix]

When you did the timing belt did you check the timing was actually correct?


OliNix
B8.5 S4 Avant - Glacier White

[Alexutz Preda]

When you did the timing belt did you check the timing was actually correct?


OliNix
B8.5 S4 Avant - Glacier White

Yes, I double checked that with my mechanic who done the timing belt and he said timing is fine 100%. Should I get a different garage to check the timing belt ? Would that be the cause of it?

[OliNix]

You can, but I would expect a garage to do it properly. It was more a concern if you had done it yourself as the timing belt may have jumped before it was changed. When you then change it and assume everything is in the right position it may not have been. I would ask them if the timing was reset with a proper kit? Were all the pulleys slackened off, the crank and cams locked in position and the new belt installed. Then the pulleys tightened up and the locking tools removed. This is the only way to be sure the timing is spot on. Some garages will just swap the belt and assume it is all fine without actually checking or resetting the pulleys.

It is also worth checking the tensioner on the timing belt. If this is either too taught or too loose it could be throwing the timing out.

[Alexutz Preda]

You can, but I would expect a garage to do it properly. It was more a concern if you had done it yourself as the timing belt may have jumped before it was changed. When you then change it and assume everything is in the right position it may not have been. I would ask them if the timing was reset with a proper kit? Were all the pulleys slackened off, the crank and cams locked in position and the new belt installed. Then the pulleys tightened up and the locking tools removed. This is the only way to be sure the timing is spot on. Some garages will just swap the belt and assume it is all fine without actually checking or resetting the pulleys.

It is also worth checking the tensioner on the timing belt. If this is either too taught or too loose it could be throwing the timing out.

Thanks for that. I’ll try that and come back with an answer ...

[Alexutz Preda]

Hi,
What’s involved in checking the wiring from the camshaft sensor ? How difficult is it to follow the wires and where do they end ? I just want to make sure there’s no issue with the wires ...
Also, what reading should I get if I measure voltage with a multimeter ? Thanks

[Crasher]

Fault code

16400 (P0016) - Bank 1: Camshaft Position Sensor (G40) / Engine Speed Sensor (G28): Incorrect Correlation

means there is nothing wrong with the wiring, that would be a short to earth or positive code, 16400 means what it says, the correlation between the crank and cam sensors is incorrect, i.e. bad timing.

[Alexutz Preda]

Fault code

16400 (P0016) - Bank 1: Camshaft Position Sensor (G40) / Engine Speed Sensor (G28): Incorrect Correlation

means there is nothing wrong with the wiring, that would be a short to earth or positive code, 16400 means what it says, the correlation between the crank and cam sensors is incorrect, i.e. bad timing.

Yep, turns out it was a slightly off timing belt issue... synchronized the timing belt as tight as possible and it starts on the first attempt with no more issues ! Thanks guys !! Really appreciate the great advice !!

[OliNix]

Yep, turns out it was a slightly off timing belt issue... synchronized the timing belt as tight as possible and it starts on the first attempt with no more issues ! Thanks guys !! Really appreciate the great advice !!

There is a tension it should be.

Be careful it isn’t too tight. It might work now but you could be putting too much stress on the belt and if so it can snap!

[Alexutz Preda]

There is a tension it should be.

Be careful it isn’t too tight. It might work now but you could be putting too much stress on the belt and if so it can snap!

Sorry actually meant “tight” as in the timing had to be done perfectly “tight”...
but I will mention to my mechanic about the tensioner not to be too tight ....
thanks for the tip !!!