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Discussion Starter #1
So i have been suffering from an intermittent cold start misfire

Only happens on coldstart and always affects cylinder 3

Misfire clears after around 10-20 secs and car behaves normally for rest of day

Garage diagnosed coil pack and plugs and changed this

Next day - problem remains

Now they are saying they want to try changing the injector

Questions
- where do i stand with the change of coil pack and plug? Should i expect a refund (they have not fixed the problem)
- injector seems plausible (under fuelling during from injector on over fuel cold start process?)
- what else could it be - wiring?

Should i try some injector cleaner?

Thanks
 

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Sounds like perhaps a leaky injector. Have you had it scanned for fault codes?
 

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So i have been suffering from an intermittent cold start misfire

Only happens on coldstart and always affects cylinder 3

Misfire clears after around 10-20 secs and car behaves normally for rest of day

Garage diagnosed coil pack and plugs and changed this

Next day - problem remains

Now they are saying they want to try changing the injector

Questions
- where do i stand with the change of coil pack and plug? Should i expect a refund (they have not fixed the problem)
- injector seems plausible (under fuelling during from injector on over fuel cold start process?)
- what else could it be - wiring?

Should i try some injector cleaner?

Thanks
Stuff you can do for free to help isolate the issue:

Swap plug 3 to another cylinder (remember your choice) and see if problem follows.

Swap coil 3 with another coil (again, remember your choice) and see if problem follows.

If not, you have ruled out coil and plug. Do one at a time, to not confuse the situation further.

If the problem remains, then continue to dig into injector issues, etc.
 
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