O2 Sensor keeps shucking up error codes!!

[manix]

Hi All,

My 2000 2.0SE Bora is winding me up!

I have an error code that just won't go away: The O2 sensor bank 1 sensor 1 is making my EML come on and has been for over a year.

When this first happend my car had trouble starting and didn't run well, so working in the parts game I got an aftermarket O2 sensor (Fuel Parts) and it solved the problem. It ran well and has not had a starting issue since. However a day after fitting the sensor the same code came back up!

Given it was running ok and had no other issues I ignored it. The the Mass Air Flow sensor went and this coupled with the O2 code was making the car run like a bag of nails! So, I replaced both sensors, this time with Bosch one's thinking that the car may like these better!!!! Well this time the EML light stayed off for around 4 days, I thought I had sorted it!!!

Why does this keep coming up when the new sensor seems to help improve the cars performance? I am now going through O2 sensors quicker than socks!!!

Anyone else had this? Could it be something else causing it to show a problem? I don't want to have to buy another O2 sensor this side of 2020!!

[FastFerret]

What did the sensors look like when you removed them?
My daughters lupo had an issue where the dealer also replaced the sensor twice and still she had a problem with the car.
It turned out to be a chafed HT lead shorting out and causing unburnt fuel to choke up the sensor.
I replaced the HT lead and the warning remained for about 30 miles till the sensor had cleaned itself and it ran perfect up until it floated away in the floods in Hull a few years ago.

[manix]

Thanks for the reply FastFerret, but that was not the issue.

I think I have actually managed to clear all codes! Shortly after fitting the Bosch sensors, the coolant temp sensor went AGAIN! So I fitted a new one and the light has stayed off for over two weeks!!! AT LAST!

So in summary for everyone else, I reccomend fitting only Bosch or OEM sensors because the cheaper aftermarket one's are a false economy, they simply do not last, at least that is what I have found.

Also on the coolant temp sensor (green cap) the cheaper makes again don't seem to last long, but this in only £10. This latest intermotor one seems to be making my car run cooler than normal. Where it used to reliably sit at 90 degrees it not sits at around 60?!!

I hope this puts something back into this forum! Hate to just use it when I have problems!!

[kite]

Where it used to reliably sit at 90 degrees it not sits at around 60?!!

You could have a failed thermostat...

[manix]

You could have a failed thermostat...

Yeah thanks. I was thinking the same, but I was a little sus that it happend straight after I replaced the temp sensor! Knowing my luck, there will now just be a string of issues one after the other!!

Never even thought about needing to do the thermostat on this car, I always think of old renaults and vauxhall novas! Will dig out how to get at it and give it a test.