E91 Misfire under load

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Benaal
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E91 Misfire under load

Post by Benaal » 23 Jul 2017, 08:25

Hi all,

had this problem a while back but it's back again.
Basically, when booting it on the motorway I'll get to about 60 and the whole engine will judder and i get the EML on. The code reads Cylinder 1 misfire.
I've had cylinder 1 coil replaced, as well as cylinder 6, just in case they numbered them wrong. still Cylinder 1 misfire.

On top of that, I've been having trouble starting it over the last few weeks. There's been the odd occasion where it turns 6 or 7 times before it takes.
Also, I am getting the smell of burning fuel at low speeds and particularly when I stop at lights etc.

To my untrained brain, this sounds like a fuel mix issue, but I was wondering what the collective experiences here thought?

Thanks,

Martin

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M60NJP
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Re: E91 Misfire under load

Post by M60NJP » 23 Jul 2017, 09:09

Hi Martin and welcome.

If the ignition 'side' is all sorted it certainly reads like a fuelling issue - the fact it's becoming difficult to start suggests you have an air leak somewhere. I'd start by tracing each patiently and check for splits or badly seated joins.

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Lewy
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Re: E91 Misfire under load

Post by Lewy » 23 Jul 2017, 21:23

Dodgy spark plug?

Benaal
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Re: E91 Misfire under load

Post by Benaal » 06 Aug 2017, 12:00

Just to put this to bed for now, I had the battery tested for another reason and found that it was faulty. Now replaced the battery and touch wood I haven't had the problem since. I'm wondering whether there was a voltage issue with running at high revs? Could it confuse the ECU?
It would certainly explain why it was dodgy when starting.

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M60NJP
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Re: E91 Misfire under load

Post by M60NJP » 06 Aug 2017, 12:10

Benaal wrote:Just to put this to bed for now, I had the battery tested for another reason and found that it was faulty. Now replaced the battery and touch wood I haven't had the problem since. I'm wondering whether there was a voltage issue with running at high revs? Could it confuse the ECU?
It would certainly explain why it was dodgy when starting.
I wouldn't expect a dodgy battery to affect running at any particular rev/speed. The voltage remains fairly constant at all engine speeds. More likely to be related to your other post!....

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