Cam position sensor woes

[Daspete]

Hi guys

I have a cam position sensor code P0340 with slow starting and hesitant acceleration.

I have replaced the sensor and checked wire continuity to the engine management which is good but I still have the code despite clearing it.

Could there be anything else that could be causing this code that I've missed?

(2001 1.9 M43tu)

Thanks in advance.

 

[Eddie Zedder]

Did you replace the sensor with an aftermarket part? It is very common as to whether they work or not.

 

[Daspete]

Yes it was febi bilstein one.
The odd thing is it worked and then I replaced the cylinder head and now it doesn't.

Replaced the crank position sensor today and running has improved massively but it still has the code and is slow to start. Has the occasional stutter too.

 

[Eddie Zedder]

This is where you could do with a friendly M43 owner nearby with a good runner, so that you can borrow his sensor .

 

[Daspete]

Very true.

I kept the original one too because I only replaced it whilst I was doing a load of other work not because it particularly needed it and that doesn't work either.

I know it's linked to the crank sensor and that's why I changed that but I can't see anything else that seems to be linked to it. Starting to think the dme may be damaged.

I changed the lambda probes, cylinder head, temp sensor and crank sensor this week.

I thought I might have been silly and put the pulse wheel on wrong but again that's right

 

[Eddie Zedder]

Any thoughts @t-tony , @Lee @NZ00Z3, @mrscalex

 

[t-tony]

Trying a known working one would rule out the sensor, as would fitting your sensor into a running car.

Tony.

 

[NZ00Z3]

I don't know too much about the M43 TU engines. The code and symptoms align for a faulty inlet cam shaft sensor.

Was there any oil in the sensor connector? If so, remove the DME and look for any oil/coolant contamination of the DME pins and connectors.

Other than that, spend the money and buy the OE sensor.

 

[Daspete]

I don't know too much about the M43 TU engines. The code and symptoms align for a faulty inlet cam shaft sensor.

Was there any oil in the sensor connector? If so, remove the DME and look for any oil/coolant contamination of the DME pins and connectors.

Other than that, spend the money and buy the OE sensor.

I removed the DME yesterday so I could continuity test all the wires. The DME connections are all pristine. The connector to the sensor is a bit grubby but doesn't seem too bad. Wonder if it could be that simple I'll try and give it a clean.

 

[t-tony]

I removed the DME yesterday so I could continuity test all the wires. The DME connections are all pristine. The connector to the sensor is a bit grubby but doesn't seem too bad. Wonder if it could be that simple I'll try and give it a clean.

Electrical contact cleaner spray is useful.

Tony.

 

[colb]

The bad starting you have is a known inlet cam sensor fault, found that out when I left mine unplugged on the Z4 after changing the ccv system. When starting it turned over a good few times before it decided to fire up. Put the connector back on it and starting was restored to instant starting. Just changed a fellow members camshaft sensor on his M43, had thrown a code for it, I think the replacement was a Hass brand which I have used before on another BMW 3 series. One thing I would say the original Bosch sensor has a stepped barrel that fits in its hole, the replacements did not have the stepped barrel and were very tight to get in, I resorted to using some wet and dry on the barrel to slim it down to get it installed in its hole. Once in enough the securing allen head screw allowed it to be pulled in fully sothe O ring seated and sealed ok. The one fitted to the Series 3 has been in for over a year and still functioning ok. The recent M43 one fitted has not thrown any codes since being fitted.

 

[Daspete]

The bad starting you have is a known inlet cam sensor fault, found that out when I left mine unplugged on the Z4 after changing the ccv system. When starting it turned over a good few times before it decided to fire up. Put the connector back on it and starting was restored to instant starting. Just changed a fellow members camshaft sensor on his M43, had thrown a code for it, I think the replacement was a Hass brand which I have used before on another BMW 3 series. One thing I would say the original Bosch sensor has a stepped barrel that fits in its hole, the replacements did not have the stepped barrel and were very tight to get in, I resorted to using some wet and dry on the barrel to slim it down to get it installed in its hole. Once in enought the securing allen head screw allowed it to be pulled in fully sothe O ring seated and sealed ok. The one fitted to the Series 3 has been in for over a year and still functioning ok. The recent M43 one fitted has not thrown any codes since being fitted.

This febi one seems to fit in easily and no tighter than the Bosch.

My starting is exactly as you described. Frustrating as there doesn't seem to be a reason for it. All other sensors are brand new too.

Going to try giving the contacts a clean tomorrow.

 

[t-tony]

Same symptoms I got with my 2000 Z3 2.0. It didn't throw a code or put the light on.

Tony.

 

[Daspete]

Cleaned all the contacts out and it still didn't work so I took the connector apart cleaned it then fitted with just the wires and it worked.
When I put the connector back together it stopped again. It appears that yellow rubber bit inside had gone a little stiff meaning it was trying to push the connector off. Works fine without that in.

Probably down to standing around off the road for ages.

Mystery solved.