Car refuses to start in cold conditions

[George Evo]

Try more injection timing and will be better.
tried on my evo with motek m800 pnp something like 450 and become better to -5 -10

[scoobyman]

No luck so far, doubled all the values in Fuel ET comp table and nothing is changed really, still takes a fair few cranks to get it started in the mornings

[scoobyman]

Ok, so after all the tips from you guys here is what i ended up with, I can say that its slightly better, i managed to start the car in -10c today, it took me about a minute cranking it on and off, but i did manage to start it!

Here are the tables that i now i have, is there anything else i should change to make it better ?


Thanks

[Holmz]

What RPM does it idle at?
You may want a timing cell just below that...
(i.e. say it idles at 850 and cranks at 600)
e.g.
0 = 380 (so a bit before TDC for ease of cranking
500 = 380 (same as above)
550 = 450 (now put in more advance to start)
750 = 460 ( increase the advance to move the idle back up in RPM)
850 = 420 (Decrease the advance to move the idle lower in RPM)
1000 = 420 (into your map)


Fuel cranking comp
Have you tried making the fuel cranking comp that is "80" at -10C go to "100" at -10C ?


Fuel comp
Have you tried increasing the comp at -10C
e.g.
TP=0 / -10C = 75 (was 55)
< I would probably get it to crank/start and then look at the whether more fuel comp is needed at a lower temp - probably with before CAT lambda numbers >

[scoobyman]

Thanks for that, i'll try those changes and see how it works today.

The car is actually running quite rich once its started, its jumping between 12.5-13,7 AFR after just starting and once ET is over 80 C it settles around 12 AFR..
It has been unaffected by my playing around with compensations as far as i can tell, it always idled very rich.

While driving, at constant throttle and no boost, i have 13,7-14.2 AFR.

Is there maybe something i could log for you guys that could help analyze this problem ?

Thanks!

[Holmz]

Thanks for that, i'll try those changes and see how it works today.

The car is actually running quite rich once its started, its jumping between 12.5-13,7 AFR after just starting and once ET is over 80 C it settles around 12 AFR..
It has been unaffected by my playing around with compensations as far as i can tell, it always idled very rich.

While driving, at constant throttle and no boost, i have 13,7-14.2 AFR.

Is there maybe something i could log for you guys that could help analyze this problem ?

Thanks!

AFR of 12 is richer than 12.5
So if it is 12.5 once it is started, then you my want to start with the cranking enrichment first and leave setting it any richer until you get it to start up first.

[scoobyman]

Alright, will do.

Another weird thing i noticed, is that even when the car has no problems starting (warm engine or warm outside), instead of actually starting up at higher revs and dropping down to idle aim, it starts with very low revs and slowly creeps up towards idle aim (900rpm) over 3 seconds or so.

I tried everything i could with idle control and it made no difference to that particular issue, is it possible that those 2 issues are related and is there anything that i could do, to make it start in a conventional way, with a slight rev-up at start-up?

[Holmz]

I think your tables were showing injector timing.
What is you ignition timing around idle?
Regarding the spark will make the power (and RPM) go down.
Advancing the spark will increase it... So one can make a hole for the idle to rest in.

If you retard it some, then you need to open the throttle up to keep it idling.

[scoobyman]

Thanks Holmz,

Here are my current ignition tables, could you recommend any cold start changes i should make ? I have absolutely no idea what range of value changes are acceptable and which are not.

[Holmz]

Thanks Holmz,

Here are my current ignition tables, could you recommend any cold start changes i should make ? I have absolutely no idea what range of value changes are acceptable and which are not.

Even better I found that the good chaps in Croyden South have moved the videos to youtube.
And then can be iPadded or iPhoned and used in the garage.

I would say start here: http://www.youtube.com/watch?v=H-zHSvZ7PSg&hd=1 as it is better to understand it, then to get the answer.
The whole list is here: http://www.motec.com.au/webinars/webinararchive/
But it would be nice to see what answer you get as well.
I would suspect that you need to see what the load value is (20, 40 , 60) which will require some logging to look at.
http://www.youtube.com/watch?v=aro9b4gnzps&hd=1
Assuming it is the 20 (which I really doubt) then the (10, 15.5, 14, 4,...) would probably need to go to (-5, 25, 14, 4,...)

By the way, where are you located? It seems we are on at the same time??