M44 1.9i Codes p0340 p0130 p0135

[Quinton]

Hi m44 massive, i finally got round to reading codes on my z3 (1998 June) m44 1.9i after clocking up 100k. Ive recently replaced ICV which solved stalling/hard start when cold but have noticed some other minor issues when driving. The codes I am getting are (reoccurring after clearing)

p0340 Cam Shaft Sensor A Circuit Bank 1 or Single Sensor

p0130 O2 Sensor Circuit Bank 1 Sensor 1

p0135 O2 Sensor Heater Circuit Bank 1 Sensor 1

Q1 So my question is if I replace the Cam Shaft sensor with OEM part will this likely clear up the O2 Sensor codes? Or is there also a problem with the O2 sensor?

Q2 Is the O2 sensor on the m44 changeable by DIY home mechanic or should I use indy garage? Cam shaft sensor replacement looks straightforward.

Q3 Can I drive the car waiting on parts?

Thank you for any advice / experience. Ive read some threads which suggest the O2 codes are related but not specifically these codes. No EML light on, I haven't checked the bulb :\

 

[colb]

Change the cam sensor with an OEM one, pattern parts may be cheaper but seldom last long. Might be worth pulling it out and giving it a clean to see if that solves your code problem before spending out.

Same for O2 sensor get an oem quality replacement after checking that the wiring is not an issue causing the fault codes to set before spending out. I replaced mine with a Bosch sensor from Eurocarparts, not cheap and they won't accept returns, sell it to you in a sealed bag. Cheaper option is a generic sensor but you have to wire the plug up to fit it. Go OEM every time.

Car shoukd be ok to drive whilst waiting for parts but you may notice a performance drop mainly due to the non functioning O2 sensor not reporting to the brain. Car will probably go to default settings with no signal from the O2.

 

[Quinton]

Thanks Colb, I've just noticed my indy garage fitted a new camshaft sensor dec 29 2017....part cost 121.37 ill have to go back and see what the options are...charged my 2 hours to fit it another 120 (took the mickey?). Ill have to check if its OEM

Anyone reading this thread in future part codes to search for on realoem for Z3 m44 1.9i 140 BHP are:

Lambda "O2" sensor BMW Code 11781247406 (Called regulating Lambda probe) Bosch OEM version circa 60 pounds on ebay
Camshaft Sensor BMW Code 12141743072 (Called a trigger contact) BMW OEM version circa 125 pounds on ebay

Ill report back after fix.

 

[colb]

Camshaft sensor codes seem to be one of the most frequent codes that people get, remove the sensor and give it a clean a build up of crud may be the cause, once clean run the car after clearing the code and see if it sets the code again. I think your M44 sensor will have a longish wire attached to it, make sure the connecting plug and socket is nice and clean when you reinstall it.

The O2 sensor should present no problem taking it out and reinstalling, it will be the first one you see in the exhaust down pipe, some cars have two sensors one pre cat and one post cat, think yours will only have a single sensor. Check by having a look along the exhaust or have a look at the OEM parts diagram using the last 6 figs/letters of your Vin number.
If you dont have a O2 Sensor socket you should manage using a ring spanner either 13 of 14 mm from memory disconnect the wiring and thread the spanner onto the sensor. When you reinstall just put some anti seize grease like copperslip on the threads, dont get any on the business end of the sensor. New sensor may well have anti seize already applied to the threads.

 

[Ianmc]

OBD2 cars have pre and post cat sensors. M44 is OBD1 so precat sensor only. Some other OBD1 cars may have two sensors, but don't know this.

 

[Quinton]

Hmmm been checking for air vacuum leaks to see if its causing o2 sensor issues before changing/cleaning part and found this under throttle manifold...new hose ordered will see if it fixes o2 sensor issue. Not sure if Camshaft sensor code is related. Will report back in a week or so.

 

[colb]

Good spot, should have mentioned doing a check for any air leaks before changing the O2 sensor, what you found may well have a bearing on the O2 sensor fault code you have. In short if the sensor is seeing unmetered air that is not being measured by the Maf sensor its likely that its thinking its running lean and asking for a richer mixture putting it all out of kilter. Shouldn't think the camshaft sensor would be connected with the air leak you found. If you have diagnostics that can view the 02 sensor with the engine running you should see it working by the voltage its putting out ranging up and down the scale if your diagnostics can do this its probably best viewed as a ossiloscope wavey line trace up and down the scale. O2 sensors don't last forever so don't be surprised if its looking a bit lazy or not working at all.