Fueling issues - injection time increase while held in cell

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I A Motorsport
 

Posts: 54
Joined: Tue Oct 13, 2009 7:17 am
Location: UK

Fueling issues - injection time increase while held in cell

Post by I A Motorsport »

This is a big main issues

car=
ecu: 69f00
address file= s14 silvia sr20det 69fxx
Bin = added
turbo= tdo5 top mount
maf/afm= z32 changed k
Injectors= nismo740 - latancy changed to 660 and k changed
Camshafts= Tomei pon cams 254
adjusted scales for max boost of 1.6 bar
Timing set =15deg
02 disabled in flags and unpluged
knock disabled
vct is removed and solinoid is unpluged

i should say that currently its reading cold enrichments maps at 81-82 c
im about to try and get it hot enough for it to swap to warm a slight issues when its visc fan and i have no fans running on the front for cooling and the stat is a standard nissan item, its 50mm alloy fan (drift car) clealry good for drifting not so much for me.. (Matt said its a current bug that should be ok after 85C)

load cell 48 @ 2800 rpm

you can see in the log that injection timing goes up while still in the same cell..

the car is being held on a dyno at 2800 rpm/ 22.5mph creating 0.5 bar boost

i have added alot of fuel low down to remove the problem of it referancing leaner mixtures for the 3 seconds tha can somtimes be a problem (smothing issue) that has been talked about in other posts.. as you ccan see from log more than 3 seconds

i have also tried to apply throttle slowly to reduce the amount of accelerator in-richment if this has worked or not i have no idea..

now what this is really doing is as follows .. so same dyno settings.. full throttle car goes to 12 afr then leans out to 14 then (injection timing goes up) back down to 12afr

now i realise that this cell will probably never been seen in real driving but regardless i want it to be right..

if im not explaing myself well please let me know as i will try a differnt way..
if you want me to change anything please suggest and i will (dyno or with nistune)
Change my bin and ill uplaod yours and try your ideas.

there have been a few issues im trying to get through and its been taken off and put on the dyno some 15 times in the past week.. its now cost me alot more than the job was ever worth an i want the pain to end.

thankyou in advance to anyone that can help or have any ideas to try.

im gonna try and get it hot enough to see what happens..

to logs with different tps increase speed
chris test 750 32 cale change.bin
(64 KiB) Downloaded 128 times
NIStune_2011-11-21_1004_02.csv
(25.73 KiB) Downloaded 120 times
NIStune_2011-11-21_0941_07.csv
(23.62 KiB) Downloaded 130 times
Matt
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Re: Fueling issues - injection time increase while held in cell

Post by Matt »

viewtopic.php?f=5&t=2158&p=15522#p15522

Had to go through each one and answer there

With regards to the AFRs changing mid cell, it just seems to be something the S14 ECU does. Several other tuners I have talked to about this so spent some time looking into it

You have to hold that cell in that part of the map for 3 seconds and then it jumps richer. Might be some safety mechanism but its definately timer based and only once you start deviating from the regular Nissan maps

I tested using standard maps and scalers etc and then changing just this area of the fuel map and holding there and the injection time will jump. Standard maps not an issue. Not tied to scalers, MAF or injector resizing

As you mention in reality its only a passing point but its not something you can work around apart from smoothing it out in the map
I A Motorsport
 

Posts: 54
Joined: Tue Oct 13, 2009 7:17 am
Location: UK

Re: Fueling issues - injection time increase while held in cell

Post by I A Motorsport »

Once again thankyou for your reply

You have said that fueling seems to increase but from what I'm seeing fueling seems to lean of for a period of 3 secs (while ref back) then richer to the afr that you input into the main maps.

It may be the way I read it. I'm sure we mean the same thing.

As I've sad I've tried inputting 12 afr across the entire area. But I assume you mean raw figure not target afr. And I havnt tried that.

So I'm assuming my best bet is to (for now ) ignor this leaning off period. And just tune as best as I can.

Regards Ian
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