Should i change camshaft position sensor (G40) ?

[welshdean]

Hi all,

Ive recently bought a second hand mk4 golf 2.0 gti.
Its not been running as it should and its been put onto the diagnostic computer and its been showing a few problems.

They were...

1. B1 Lambda sensor
2. Camshaft position sensor (G40)
3. Battery voltage too low ( or something along those lines )

Ive now replaced the B1 lambda sensor and there still doesnt seem to be much improvement, if any.
After it was replaced, it was put back onto the diagnostic computer and its read the same problem. B1 LAMBDA SENSOR, but its been changed 

So my question to you is...

why did it pick up AGAIN the B1 lambda sensor when its been changed, and also if this is going to happen again is there any point in me changing the camshaft position sensor?

my problems are that its overfuelling, sluggish, and sometimes splutters and just generally no gutts all around.

If you could help i would very much appreciate it

[GTi_James]

alright mate,

have you tried cleaning the hole the sensor goes into, also there maybe a fault with the wire to sensor as well, did you get OEM? i would myself change the O2 sensor as well as a precausion and check the exhaust for blowing. you'll get a sluggish feel if the battery is on the way out, suggest new battery and alternator check as well as fuel filter and clean your temp sensor. the camshaft sensor would need replacing  but if it didnt show up on the second scan then it could just be your sensor having a moment

[Nino]

He brought it up to mine and i scanned it or him, first we found 3 codes:
1: G40 sensor.
2: B1 lambar.
3: Batt low current or something.

I cleared the codes and he went home, the next day he replaced the B1 lambar and brought the car backup to me last night. I scanned it again and there where 2 codes.
1: G40
2: Lambar B1.
I figured that even thou he chabged his lambar the code was still in the ecu so i clear them again but this time i disconnected his G40 and cleaned it out with eletronic contact spray. Then sent him on his way. However he is saying that his car is still sluggish.....
Would a faulty G40 cause this?

[welshdean]

After Nino cleared the fault for B1 Lambda sensor I went home and was getting between 28-30 mpg. I went out in the car today and it spluttered once or twice and I'm only getting around 20mpg today. So as I don't have access to a diagnostic machine myself I'm unable to tell if the fault has 're-appeared . I've been looking through the posts and as I'm completely clueless I'm not finding anything to point me in the right direction. I'm just thinking that if I go and buy a camshaft position sensor , is this even going to make any difference.

[Nino]

Better off asking in the mk4 section as not to many people look in this section, any mods able to move this topic?

[Wazzzer]

I only have powers in the mk4 section, I'll ask one of the bigger boys to move it

[Nino]

Thanks wazz

[Dalo Harkin]

You sure you replaced the right lambda sensor, or is there just one on yours?
If you had an issue with the G40 boy would you know about it, car was undriveable.
You can get the battery low after removing the battery or taking the terminals off

[welshdean]

Well I was told by the woman at eurocarparts that the bank 1 lambda sensor was the one before the cat, which is the one that I replaced

[MattyV6]

A dodgy cam sensor can deffo make it run rough.

I had a dodgy one on mine and it was over fueling pretty bad, so much so that it would spit flames.

It might be cheaper on yours but mine was just over £100 from VW. It now runs spot on