Shuddering/misfire on initial cold start, after that fine?

[crawlgti]

Have had this issue for a few months now and can't seem to get to the bottom of it.
Misfire / shudder on initial cold start for about 30 seconds to a few minutes. I can hear air/hissing noise then all of a sudden it kangaroos. After a few mins it's absolutely fine. No CEL's. When it's warm she seems to drive fine, although I feel there is slight hesitation under load sometimes.

I have recently had
- injectors serviced + carbon clean
- Fuel filter changed
- Fuel pump was replaced about 1.5 years ago
- New coil packs
- VCDS not throwing up any significant codes, no misfire or air flow sensor

Anyone have anything like this or can point me in the right direction?

[pudding]

Has it had a runner flap delete?

[TheBALDpuma]

I had very similar symptoms and it was the throttle body. Well in the end it wasn't, it was the wiring to the throttle body causing the problem.  Eventually it became undrivable and I had a bunch of warning lights plus limp mode

[crawlgti]

Has it had a runner flap delete?

No it doesn't

[crawlgti]

I had very similar symptoms and it was the throttle body. Well in the end it wasn't, it was the wiring to the throttle body causing the problem.  Eventually it became undrivable and I had a bunch of warning lights plus limp mode

That's helpful, is it easy to check the wiring to the throttle body? Wouldn't know where to begin. Did you have the throttle body replaced as well?

[loop]

I’ve had similar and it was the NOX sensor control unit.
Have previously had throttle body removed and cleaned as well which cured a throttle control valve fault.


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[TheBALDpuma]

I had very similar symptoms and it was the throttle body. Well in the end it wasn't, it was the wiring to the throttle body causing the problem.  Eventually it became undrivable and I had a bunch of warning lights plus limp mode

That's helpful, is it easy to check the wiring to the throttle body? Wouldn't know where to begin. Did you have the throttle body replaced as well?

Sorry for the slow reply.  Yeah replacing the TB was the first thing we did, but the problem came back a month or so later.  Then we flashed the ECU and the problem came back again - so then last option was to replace all the wiring which fixed it for good.  Cost a bit of money as it was being done at a garage - as for how hard it is to check/do I have no idea!