ER34 hard to start [video]

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lolo37
Posts: 14
Joined: Tue Sep 04, 2012 9:40 am

ER34 hard to start [video]

Postby lolo37 » Thu Apr 06, 2017 5:37 am

Hi guys,

I'm not a great nistune specialist and can't find any solution to make my RB3025 start properly.

engine setup : RB3025 neo, blown HPXN1, 1200cc injectors, gtx3582r

see the vidéo I made:

https://www.youtube.com/watch?v=tZtCvFjYj54&t=19s

latency is 1600 ; K is 540

It is quite strange that sometimes it begins to start and combustion is stopped 2 seconds after...

Any ideas to make it start properly ?

Matt
Site Admin
Posts: 7955
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
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Re: ER34 hard to start [video]

Postby Matt » Thu Apr 06, 2017 7:18 am

Starting is problematic due to the size of the injectors and the main table to be concerned with is crank enrich. I've found with 1000CC ID injectors on my NEO that it is also sensitive to battery voltage and the values in the crank enrich table

Latency try setting around 1250uS which is what I've been using. K and latency are only used after starting

Crank enrich table values when warm seem to work when set to about 10ms which is very large for these injectors (assuming you have IDs) but they need a lot of opening time during crank (and when battery voltage is low)

lolo37
Posts: 14
Joined: Tue Sep 04, 2012 9:40 am

Re: ER34 hard to start [video]

Postby lolo37 » Thu Apr 06, 2017 8:58 am

Ok so it seems i find a solution and maybe the problem.

I corrected the 10ms for the crank enrich after 50degres Celsius. Instead of the 70ms i put previously.

I cranked the engine and nothing special but i looked at the battery voltage and it was 8Volts when cranking.
Interesting thing.
Then i tried to restart the car and after 1.5seconds cranking, the key slided from my fingers and boom! Engine started!
And i could do this repeatably again and again.!
Engine inertia recovering 12Volts makes it starts!

Seems my long battery cables and my 1400cc's (yes i mistook myself, they are 1400 :-/) needs a lot of power to pulse.

The 70ms were needed to start the engine with 8volts crancking... now with the short cranking technique, 10ms is perfect.

Thanks you alot Matt ! ;-)

Matt
Site Admin
Posts: 7955
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: ER34 hard to start [video]

Postby Matt » Fri Apr 07, 2017 8:44 am

Excellent :D


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