Zafira b 1.6 on a 55 plate 88k miles on the clock.
Trouble started a month or so ago while driving along motorway, went from 60 to 70 zone and put my foot down to speed up which was on a incline, car felt like it was losing power and revs were up and down and the service light came on. Got off at the next junction and drove home at 30, car seemed to be lacking power and revs were a little erratic but never stalled and got home, although car seemed to struggle more on hills. Light came on, off, on all the way home.
Next day car started fine and drove to work fine, no issues on motorway, came off the motorway through a tunnel and again when I hit a hill on the way out car struggled, light on and struggled up the hill and continued to struggle for the remaining minutes of my journey.
I changed the plugs didn't make a difference, changed the coil pack (Delphi) still the same.
Car starts fine and drives for a while and seems fine, even on hills but then it just goes... feels lumpy, loud and struggles especially with hills and the light hasn't been on in a few days but the car seems like its getting worse - happening quicker and more often.
About a fortnight ago car stalled twice from start - car had been parked for 15 mins outside shop and went to start it. Started fine but then the revs just dropped and it cut out before I even attempted to move. Tried again - did the same and then 10 mins later tried again and it went, drove the 2 miles home and it struggled more and more the longer I drove. Got it home and started twice no problems once cold. After this I changed the crank sensor but made no difference and I have cleaned the throttle body.
Haven't driven the car in a while but started it up last night and checked the live data - thinking it could be the cat. Started car and put it on live data. O2 sensor 1 was cycling between 100mv-800mv with sensor 2 sitting at a constant 59mv. I let the car heat up to 80c and then revved it for a few minutes to get the cat lit. After 2 minutes and I presume when the cat kicked in, the service light came on and car started running badly again and both O2 sensors voltage dropped - Sensor 1 sat very low at 59mv occasionally hitting 78mv and sensor 2 sat at a constant 39mv.
So does this point to cat failure as both sensors appeared to be working nicely from cold to 80c and as soon as the cat kicked in it all went downhill. Could it be anything else before I shell out for a new cat?
Thanks
Trouble started a month or so ago while driving along motorway, went from 60 to 70 zone and put my foot down to speed up which was on a incline, car felt like it was losing power and revs were up and down and the service light came on. Got off at the next junction and drove home at 30, car seemed to be lacking power and revs were a little erratic but never stalled and got home, although car seemed to struggle more on hills. Light came on, off, on all the way home.
Next day car started fine and drove to work fine, no issues on motorway, came off the motorway through a tunnel and again when I hit a hill on the way out car struggled, light on and struggled up the hill and continued to struggle for the remaining minutes of my journey.
I changed the plugs didn't make a difference, changed the coil pack (Delphi) still the same.
Car starts fine and drives for a while and seems fine, even on hills but then it just goes... feels lumpy, loud and struggles especially with hills and the light hasn't been on in a few days but the car seems like its getting worse - happening quicker and more often.
About a fortnight ago car stalled twice from start - car had been parked for 15 mins outside shop and went to start it. Started fine but then the revs just dropped and it cut out before I even attempted to move. Tried again - did the same and then 10 mins later tried again and it went, drove the 2 miles home and it struggled more and more the longer I drove. Got it home and started twice no problems once cold. After this I changed the crank sensor but made no difference and I have cleaned the throttle body.
Haven't driven the car in a while but started it up last night and checked the live data - thinking it could be the cat. Started car and put it on live data. O2 sensor 1 was cycling between 100mv-800mv with sensor 2 sitting at a constant 59mv. I let the car heat up to 80c and then revved it for a few minutes to get the cat lit. After 2 minutes and I presume when the cat kicked in, the service light came on and car started running badly again and both O2 sensors voltage dropped - Sensor 1 sat very low at 59mv occasionally hitting 78mv and sensor 2 sat at a constant 39mv.
So does this point to cat failure as both sensors appeared to be working nicely from cold to 80c and as soon as the cat kicked in it all went downhill. Could it be anything else before I shell out for a new cat?
Thanks