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rough idle after changing injectors


loockheed

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hi there 

I have just changed from side feed 740 nismo injectors to asnu 800 long nose injectors and have rough idle and stalling problems on a jdm forester sti  04 plate sg 9

I am completely new to ecu tuning and need to know if this is damaging my engine ,injectors ,or ecu ? I have just down loaded the relevant software so I can look in to it before I drive the 80 miles too the proper mapper . 

sorry for such a simple question and please answer in a way a child can understand and thanks in advance

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The increase in injector size will be causing it to be rich running. You will need to adjust injector data and the fuelling to compensate for the new injectors.

If you post you map from the ECU we can advise the settings that will need to be corrected.

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1 cleared ecu fault - idle returned to near normal 

2 tested anti lag - idle reverted to rough 300/400 rpm wanting to stall.

3 check ecu faults, none found

log attached to this post, any help and advice is appreciated.

Is anyone in the UK, south coast that can teach me how to use the link G4+ ?

Thanks Wil

ECU Log 2017-10-18 11;39;14 am.llg

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11 hours ago, loockheed said:

1 cleared ecu fault - idle returned to near normal 

2 tested anti lag - idle reverted to rough 300/400 rpm wanting to stall.

 

What motor and does it have hydraulic lifters. Being new to tuning I would get the basics right first before playing with motorsport features

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Hi 

my car has solid lifters (shimless) I'm just struggling with how to find and send the map , the engine is an ej 22 stroked to 2.35 .

I only turned on anti lag because it seamed to reset the idle before I changed the manifold and injectors , there doesn't seam to be any air leaks that may cause rough idle

again sorry for such simple questions and yes it does seam to be running rich as exhaust reeks of fuel  

 

 

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Most likely you will just need to reduce your "master Fuel" number a little.  Yours is presently set at 12ms, since your injectors are about 8% bigger then reducing this number to 11 should reduce the pulse width by about 8% and get you in the ball park.

You may even need to drop it a little further but try it and see.

GWJTgeq.png

 

Also once you actually get to the tuner, please suggest to them that they do a firmware update before they tune - yours is very old and there have been many fixes and improvements since.

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On ‎23‎/‎10‎/‎2017 at 10:52 PM, AbbeyMS said:

Have you inputted the new injectors battery offsets numbers?

hi mark

I have recently been to yours for geometry and dealt with scott , 

is changing injector b offsets something I should do ,as I am a complete novice ?

 

 

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8 hours ago, loockheed said:

thanks adam 

I have done that , is there anything I can do to stop the motor stalling it seams like its hunting from 300 rpm to 1200 rpm when enrichment has finished .

it does this for about 15 to 20 seconds and then stalls .

 

If you post a log and map we might be able to improve it https://www.youtube.com/watch?v=_P1LRANeO4A, but in your earlier logs your lambda is not working so without that we havent got much to work with.

Originally you said you just needed to get it running good enough to take it to the tuner, is it still not driveable?

 

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