startup parameters SR20DET, 2L 4Cyl.

[clem]

Hi my problem is very hard engine start, especially when cold (like -5°C) . Cranking RPM is about 180 to 190 RPM cranking ignition angle 15btdc, same as at idle speed (1000RPM). how much timing should I use for startup? I do not want to ruin my WBO sensor with using try and error method for too long. same with the fuel dose, how much % should it be approximately from the idle speed dose?
is there a rool of thumb for these values?
thanks a LOT

[Jadzwin]

Don't worry about your LSU sensor.
For ignition advance during cranking try about 10 degrees.
For fuel it is trial and error process You should start with lower dose and increase it if the engine does not start.
If you use platinium / iridium spark plugs, replace them for standard plugs for the time of engine startup tuning (to prevent them from damage).
In the latest software there is new table, that allows lower the fuel dose in function of cranking time.
You can also enable prime pulse functionality.

From our experience "batch all injectors during cranking" option helps a lot.

[PBU]

These are mine.
4 cyl 2.0 l turbo cosworth.
Starts very good cold ( whitout throttle ).
This engine needs rich fuel to start !

[clem]

Thanks a lot!
@PBU
Which Injector size do you use? I have 580ccm

[PBU]

411cc

[bmwmaster]

Also maybe check your idle valve position. It must be open while cranking especially without throttle.

[PBU]

Also maybe check your idle valve position. It must be open while cranking especially without throttle.

Correct. I have this setting also to 90% while cranking.

[gregpe]

hi
Also is worth to use cranking time correction table....help if for some reason engine do not start as quick as needed..

[clem]

Thanks pbu.
my Idle valve works correctly, MAP is approx. 90 to 92 kPa (is this a normal value?)

time correction standard setting is to become less fuel over the time,
gregpe do you think it would be better getting even more fuel?

[gregpe]

nope you need more on the beginning and decreasing with cranking time to avoid flooding spark plugs.. works really well .

[Jadzwin]

90 kpa on ilde is too high if you have oem camshafts.

[clem]

no, sorry I did not mention, 90 kpa during cranking! 40 kpa on idle. with tomei 260° 12mm cams.
ok thanks for all the input! I am sure many people will have similar questions

and how can iridium plugs be damaged by fuel? I looked up the internet but did not find one thing about that. could you please explain jadzwin?

kind regards

[gregpe]

they are very sensitive for flooding and easy sparking "inside" the spark plug between insulator and side of spark plug.. once it happened even cleaned they seems to do this again.. and basically you need to throw them in to bin... so beter save them once you have a decent fuel map..

[clem]

Thanks for all the input!

Engine now starts VERY good in cold condition, needs some tuning in hot CLTs. Also may be a heat soke problem due to suboptimal IAT sensor position...

THANKS