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Hi all,
Currently looking at a 2011 Vauxhall Corsa, A12XER.
Customer complaint, filled up with fuel and on the way home the MIL came on.
I scanned and had a P0420, looked at scan data and found at idle the rear O2 is fixed close to 0 volts but is showing activity while driving. There is an exhaust leak on a flexi section between the cat and downstream sensor, so that is my first repair and then will probably do an oxygen storage test.
My reason for the post is relating to full throttle and driving the system rich.
Is there any reason that the system won’t be driven rich under full throttle acceleration?
Also, if anyone has any other input I’m happy to hear it.
A leak before the rear o2 will most likely cause the o2 to go lean. Pump the brake pedal and see if the o2 go lean, release it and it should go to at least 800 mv
Replaced the blowing flexi section today. The rear sensor heater is probably shot as it took an age to start responding. Would need to check current to confirm. Also O2 storage capacity isn’t great at less than 1 second. There are also other issues with the car and with 150,000 miles on the clock I’m not sure how much the customer will want to spend on it.
I still don’t understand why the fuel mixture isn’t driven rich under full throttle acceleration. The upstream O2 sensor just carries on switching as normal.
That would be the ideal thing to do. The garage doesn’t want to spend any more time on it and the customer is going to try it and decide if they want to Spend a bit of money on getting it up together.
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