I have just aquired a 1.9 1997 Z3. Strange problem it is difficult to start in the morning and if and when it does it has a terrible miss fire. This sometimes clears after a few minutes or can sometimes take several miles to clear. The rest of the day it is fine. Only happens in the morning.
Have changed coil pack plugs filters still no joy
Any ideas
Poor Starting in the Morning then fine all day
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- Joined: Mon 17 Oct, 2005 18:02
- Posts: 455
- Location: Zminec, Skofja Loka
- Contact:
Diagnostics
Now you see the folly of changing things such as coil packs in the hope that it may cure the problem! that's the kind of thing garages do when they have no idea . . .
after spending a not-inconsiderable amount of money, yu only know what the probelem is NOT caused by!
It could be a fuel pressure (ie pump) problem, or it could be a tmeperature sensor problem, or and air leak.
You need a decent diagnostic job, rather than guessing, but first check the rubber intake trunking between the air flow sesnor and the throttle body, and also the hoses going into the inlet manifold for damage and leaks.
after spending a not-inconsiderable amount of money, yu only know what the probelem is NOT caused by!
It could be a fuel pressure (ie pump) problem, or it could be a tmeperature sensor problem, or and air leak.
You need a decent diagnostic job, rather than guessing, but first check the rubber intake trunking between the air flow sesnor and the throttle body, and also the hoses going into the inlet manifold for damage and leaks.
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- Joined: Mon 17 Oct, 2005 18:02
- Posts: 455
- Location: Zminec, Skofja Loka
- Contact:
Fuel Pressure
It's possible for the fuel pressure to be too low on the first start, due to such things as a sticky pressure regulator or a low output from the pump, either of which would increase the time taken to build up full pressure after the initial start..
A fuel pressure check would be a basic part of the diagnostic work, as these problems do not provide fault codes.
A fuel pressure check would be a basic part of the diagnostic work, as these problems do not provide fault codes.