1.9 struggling to start

KaiJepson

Newbie
British Zeds
Joined
Dec 27, 2023
Points
4
Location
Surrey
Model of Z
1.9 Roadster
Hi all,

My z3 recently has started to struggle to start, it's not a battery as it does try and occasionally will start but then rumbles down and stops again, after a few tries it will start properly and after 10 seconds it idles fine. I'm not sure what the problem could be and don't have a code reader as the z3 only has a 20 pin so need an adapter too.
 

the Nefyn cat

Zorg Guru (IV)
Supporter
Joined
Oct 19, 2014
Points
174
Location
Actually in Nefyn. My, that took a while.
Model of Z
2.2i Sport
A code reader will save an awful lot of guessing and possibly expense. I've got an earlier version of one of these and it's pretty much essential, the adaptor leads aren't expensive, either. Not compared to what a garage will rook you, anyway.
 

colb

Zorg Guru (V)
British Zeds
Joined
Nov 25, 2012
Points
178
Location
Newport, South Wales,UK
Model of Z
Z3 M43 1.8 (1999) and Z4 E85 2.5 (2003)
Good advice from the cat, code reader essential for all BMW's, the Creator 310 or 410 with a 20pin adapter will be a good buy. See if there are any codes and take it from there, could be a bad or dying camshaft sensor they do affect starting when they are failing. If you find a code for the camshaft sensor that would confirm its the issue. Replace with oem brand, no cheap brands always use Bosch or Siemens although I have had success using Hass brand sensors which are cheaper than oem brands. Also check all the rubber inlet boots and vacuum pipes across the engine for splits and holes that let unmetered air into the engine that has not been measured when passing through the Maf sensor.
 

bonbon

Zorg Legend
Joined
Mar 13, 2012
Points
75
Location
Israel
Model of Z
19L Auto
1. Wait for a few seconds after the instrument panel lights go out before starting
2. Check there are no leaks in the piping. (This is the most common problem - I just had this problem for 10 months and had leak in a problem in small pipe exiting from the MFC)
 

TriumphZ3

Zorg Addict
Supporter
Joined
Aug 2, 2023
Points
49
Mine does this rarely but just often enough to worry me - it starts first time but sometimes rumbles a bit as if down one cylinder, then picks up and drives perfectly. However if I park for a few minutes after a good warmup and try to start, sometimes it cranks for a long time. It's a rare occurrence but sometimes worries me. I have a good code reader and it shows nothing wrong.
 
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