Needing a bit of help here guys I have a 320i with cold starting issues ....
It's an 1989 320i auto
To start the car from cold you have to depress the accelerater pedal fully for it to fire up, once running it runs with a slight hunt until warmed up to normal operating temp.
There are no air leaks and I've changed the plugs, also I cleaned the inlet throttle body and tps aswell as the icv.
I remember seeing a post about 320i ecu's having problems with cold starting issues or something and dealers at the time were retrofitting relays between the temp sensor and ecu? probably the next thing I need to look into....brian?
Any help would be much appreciated thanks
Azzy
320i cold start issue
Moderator: martauto
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Brianmoooore
- E30 Zone Team Member
- Posts: 49353
- Joined: Mon Jan 10, 2005 11:00 pm
IIRC, the problem with the 320i was over fuelling at start up, and the mod. was to add a relay, activated by the starter signal, that switched a resistor in parallel with the 'blue' temp. sensor, making the ECU think the engine was hotter than it was, and reducing fuelling just while the starter motor was operated.
The hunting you describe indicates a weak mixture, rather than rich, so the first thing I'd do is have the injectors rebuilt, in case their flow rates are down, and possibly leaking fuel into the inlet manifold while the car is stopped, which will make starting difficult.
The hunting you describe indicates a weak mixture, rather than rich, so the first thing I'd do is have the injectors rebuilt, in case their flow rates are down, and possibly leaking fuel into the inlet manifold while the car is stopped, which will make starting difficult.
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Brianmoooore
- E30 Zone Team Member
- Posts: 49353
- Joined: Mon Jan 10, 2005 11:00 pm
They need to be cleaned, worn parts replaced, and calibrated for correct flow rate and balance.
If you look in our traders' section, you will find 'injectortune', who has rebuilt hundreds of injectors for zone members.
If you look in our traders' section, you will find 'injectortune', who has rebuilt hundreds of injectors for zone members.
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Brianmoooore
- E30 Zone Team Member
- Posts: 49353
- Joined: Mon Jan 10, 2005 11:00 pm
How much difference rebuilt injectors makes depends entirely on how bad they were in the first place, but by 100,000 miles they will each have opened and closed around 40 million times, so there's a good chance they will be well past their best.
E30s vary from most of their contempories because their (post '87) electronics was far more sophisticated than others, but still without any monitoring (lambda sensor) of the actual mixture strength. This means that the ECU provides pulses to the injectors to provide the correct mixture strength assuming that a given length of pulse will inject a certain amount of fuel, without any attempt at compensating for worn injectors, as a later engine would, so, without known good injectors, it is impossible to set up any other adjustments on the engine.
E30s vary from most of their contempories because their (post '87) electronics was far more sophisticated than others, but still without any monitoring (lambda sensor) of the actual mixture strength. This means that the ECU provides pulses to the injectors to provide the correct mixture strength assuming that a given length of pulse will inject a certain amount of fuel, without any attempt at compensating for worn injectors, as a later engine would, so, without known good injectors, it is impossible to set up any other adjustments on the engine.