Emissions light and hunting idle on Ph2 172

[Mart16V]

As above, really! Car has been hesitant to pull smoothly when cold and the idle is a little erratic (500-1000rpm) when warm. Emissions light came on today.

Lambda sensor? Knackered cat?

Any other thoughts? Am running it on 98RON Shell juice......

Ta,
Martin

 

[andrewrobert87]

I have exactly the same issue! :S also a slight misfire when in low revs accelerating - my mate plugged it into the diag machine and it came up with ''distructive misfire' :S well we already new that due to the lumpy idle and MISFIRE when driving lol ive changed the igniation pack and still the same problem! dont know what else i can do with out chucking new parts at it in a trail and error sorta thing

 

[Jonny1*2]

As above, really! Car has been hesitant to pull smoothly when cold and the idle is a little erratic (500-1000rpm) when warm. Emissions light came on today.

Lambda sensor? Knackered cat?

Any other thoughts? Am running it on 98RON Shell juice......

Ta,
Martin

Sounds pretty normal to me mate. When cold, they don't really pull tbh. Idle does rev up and down even when warm. Lambda might be on the way out though, but it might just be the downstream one as the upstream sensor would cause you all sorts of issues.

 

[Mart16V]

Thanks for that, going for diagnostic tomorrow with local specialist service centre. Still under warranty with dealer so fingers crossed.......

 

[Mart16V]

Work done, was downstream Lambda sensor. Just going to pick it up so hopefully problem resolved....... Sadly will have to give back the Jag XK8 that I had as a loan car!!!