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EML light - aging lambda?

Discuss problems you have had or are having with your Z4
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Crazy Harry
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EML light - aging lambda?

Post by Crazy Harry » Sun Jul 15, 2018 1:50 pm

I had the EML light up yellow on me last night.

Unfortunately it lit just as I made a foot to the floor overtake on one of our rural Norfolk roads (but managed to keep the seat clean!) so tucked straight back to my side of the road and pottered the mile or so back home - with a bewildered Suzuki 'Wagon R' driver on my tail - still not got over the shame of that :thumbsdown:

By using INPA (and a child) I've got the following error code
z4_1.PNG
z4_1.PNG (132.83 KiB) Viewed 482 times
Looking in the error history I see this had happened three or four times before - the same code 'signal too slow' but not during my ownership (eighteen months so far). I'm assuming that fault this is going to come back and I will need to change the sensor soon. So is it expensive and difficult to get at? - says rear CAT so I hope not.

The car is a 57 plate on just over 44K. As I've not seen this error before do you think an aging sensor has been changed in the past? How frequently do they need replacing. No short runs in the car; being out in the sticks its all warmed through before you get anywhere not like start stop urban driving.

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Smartbear
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EML light - aging lambda?

Post by Smartbear » Sun Jul 15, 2018 2:26 pm

Crazy Harry wrote: Sun Jul 15, 2018 1:50 pm I had the EML light up yellow on me last night.

Unfortunately it lit just as I made a foot to the floor overtake on one of our rural Norfolk roads (but managed to keep the seat clean!) so tucked straight back to my side of the road and pottered the mile or so back home - with a bewildered Suzuki 'Wagon R' driver on my tail - still not got over the shame of that :thumbsdown:

By using INPA (and a child) I've got the following error code

z4_1.PNG

Looking in the error history I see this had happened three or four times before - the same code 'signal too slow' but not during my ownership (eighteen months so far). I'm assuming that fault this is going to come back and I will need to change the sensor soon. So is it expensive and difficult to get at? - says rear CAT so I hope not.

The car is a 57 plate on just over 44K. As I've not seen this error before do you think an aging sensor has been changed in the past? How frequently do they need replacing. No short runs in the car; being out in the sticks its all warmed through before you get anywhere not like start stop urban driving.
Hi, seems a low mileage for lambdas Harry-you could try some cataclean product first and see if it stops the issue?
Do you use super unleaded? That’s supposed to have cleaning properties as well :thumbsup:
Rob
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Crazy Harry
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EML light - aging lambda?

Post by Crazy Harry » Sun Jul 15, 2018 2:39 pm

Hi Rob, cataclean may be the way to go, but I might do nothing for a few weeks and see if I get the error code again. Norfolk roads are great but we don't have any motorways or long stretches of duel carriageway to really build the heat through the exhaust system - last year I was over to Oxford a fair bit so the car got long constant speed runs. Maybe I need some good road trips :thumbsup:

I also wondered about just cleaning the contacts between the sensor and the loom just in case the 'slow signal' reference relates back to poor connectivity. That said I'm more than happy to be guided by the forum.

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EML light - aging lambda?

Post by Scooba_Steve » Sun Jul 15, 2018 8:15 pm

Look like an after cat one, bigger job that the pre cat to replace. Worth trying some cleaning stuff as these sensors aren't subject to the same heat etc as the pre cat ones so don't often fail. Cleaning contacts can also not hurt. Failing that, I'd be tempted to drop the exhaust, replace the gaskets and bolts and do both sensors.
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Crazy Harry
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EML light - aging lambda?

Post by Crazy Harry » Sun Jul 15, 2018 8:31 pm

Scooba_Steve wrote: Sun Jul 15, 2018 8:15 pm Look like an after cat one, bigger job that the pre cat to replace. Worth trying some cleaning stuff as these sensors aren't subject to the same heat etc as the pre cat ones so don't often fail. Cleaning contacts can also not hurt. Failing that, I'd be tempted to drop the exhaust, replace the gaskets and bolts and do both sensors.
I'm planning on doing all the suspension at the rear - I've got a complete rear subframe that I'm going to referb/rebush and swap in next year so an exhaust refurb could be done at the same time - along with brake pipes and anything else that gets unbolted!

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mr wilks
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EML light - aging lambda?

Post by mr wilks » Sun Jul 15, 2018 8:49 pm

Try changing the fuel both where you buy & octane , don't be afraid to mix 95, 98 & 99ron in one tank & then try a decent heat cycle of 45mins - hr not pottering :oops:
I had the same light shortly after buying latest ZM , kept resetting then it would re-appear a day or so later , it had been on constant for 2 weeks then heading off for a weekend away i had half a tank of 99Momentum in then brimmed it with 95 ( yea i'm not one of those fuel snobs :o it says on filler flap 95-98Ron so that's what it gets )
Within 100 miles it had reset itself & not returned as yet ( 400 miles later) at no time did the car run any different
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