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        General >> Problems >> H02 sensor ?
        
(Message started by: reedyone on Jan 29^th, 2017, 12:16pm)

Title: H02 sensor ?
Post by reedyone on Jan 29^th, 2017, 12:16pm

95 cosworth 2.9 , using a hand held OBD reader I'm getting a fault reading of HO2 bank 2 sensor 2 high voltage , ive changed the sensor after the cat on the N/side exhaust and cleared the fault code but it comes back on . the wires at the plug all seem ok , I'm I missing the obvious here ? help.....

Title: Re: H02 sensor ?
Post by Scorpio_Mike on Jan 29^th, 2017, 12:37pm

Could be a short in the wiring loom - the insulation breaks down and crumbles :'(
Wiring around the engine area seems to suffer most.

Title: Re: H02 sensor ?
Post by reedyone on Jan 29^th, 2017, 5:49pm

when the sensor plugs in under the car is there another connection in the engine bay as it seems to disappear into the harness ,where do I disconnect at the opposite end to test the wires ?

Title: Re: H02 sensor ?
Post by Simmo on Jan 29^th, 2017, 6:24pm

This page (http://www.fordscorpio.co.uk/24vlooms.htm) gives detail of the connections with wiring colours and may help you trace the wires. ;)

This wiring diagram from Snoopy (https://onedrive.live.com/?cid=EB36F845EA9B8FB6&id=EB36F845EA9B8FB6%21813&parId=EB36F845EA9B8FB6%21146&o=OneUp) may also help. ;)

Title: Re: H02 sensor ?
Post by reedyone on Jan 29^th, 2017, 10:06pm

cheers , looks like fun !! :( it least its still running good just mpg is a bit poor 18.5 round town :(

Title: Re: H02 sensor ?
Post by Scorpio_Mike on Jan 29^th, 2017, 10:25pm

on 01/29/17 at 22:06:53, reedyone wrote:

cheers , looks like fun !! :( it least its still running good just mpg is a bit poor 18.5 round town :(

Try running a 4 litre Jeep and then you'll have something to complain about :o
I'd be very happy to get 18.5 round town :D

Title: Re: H02 sensor ?
Post by amigafan2003 on Jan 29^th, 2017, 11:29pm

"Sensor 2"'s are post cat sensors - they don't affect the running of the car at all, they are just there to monitor the condition of the cat.
You can ignore it (or even remove both post cat sensors - the car wont care).

The pre cat sensors are the ones that affect the fuelling.

Title: Re: H02 sensor ?
Post by a900one on Jan 30^th, 2017, 11:53am

18.5 seems ok to me, I get about the same, and 24-25ish on a run, depending on size of shoe ;D ;D.

Title: Re: H02 sensor ?
Post by reedyone on Jan 30^th, 2017, 7:44pm

I didn't realize the post cat sensors didn't effect the running ! something else ive learned ,cheers , the emissions were a bit high at MOT time and when I got the fault code up I just thought it was that . Scorpio mike ive a 1959 newyorker as well 6.8L does 10 mpg on a run I don't dare think what it is around town ;D never thought my discovery 1 would be my economy car !!! thanks everyone