S14 SR20DET holding on to closed loop??!?!?!

[STATUS]

i still cant sort it out with 74F00 via this method.

[Matt]

Is this using the 74F0F feature pack update?

Please call/email some time to discuss

[unex]

i still cant sort it out with 74F00 via this method.

for me almost every time helps changing ECU to 69F. Try it if you have one.

[Matt]

I have a patch harness to run 74F00 etc on my S14A. I'll try it next time I get a chance. Using the feature pack Total injection multiplier for injector upgrades means not moving TP from factory so the O2 feedback scales will not need to change

[Matt]

S14 KA24DE has an injection adjustment parameter of sorts

Okay an update on this now I've had time to get back to this in the R34 code. The number is 16 bit (0-65535) but only the top half is used by the code (0-255 range)

The adjustment does work, in 256 value increments so you can increase the total injection time as required in big steps. However most cases we want to reduce the total injection time (to compensate for larger injectors) and this isnt going to go any lower

For example S14 KA24DE and R34 RB25 both have this constant = 128 (0x0080)

Changing the constant to use only the MSB (upper digit) and then an update of the code, for increasing the injection time would only be available with the stock ECU from what I have determined so far

example:

INJECTION_ADJUST_CONST,&H1FE2,1,1,1,1

[Matt]

More updates. I've just about spent a whole day just on small sections of code and running it through a simulator to work out things

ER34: I've found an additional total injection divisor. This allows between 0.5x - 8x the original injection time. So for injectors upto 370x2 = 740CC on an R34 changes can be made to a standard ROM image with no extra firmware. This divisor also gets used for crank enrichment, so adjusting cranking tables will not be necessary

To get higher adjustment I've updated the section of code to use the Total Injection Multiplier number, like with other ECUs. Will still include this divisor in future releases of the software as an option

Not too sure if S14 KA24DE has this divisor, will need to check through the code again. I couldn't find the same routine after a quick search

[Matt]

Gone through the S14 KA24DE code again and there is no additional injector divisor like with the R34 ECU so the Feature Pack firmware would be required to change injection without affecting TP scalings. I've finished the coding for this today and testing tomorrow

After this I will look into the closed loop RPM and TP limits where available for these ECUs where TP rescaling is required, to assist in resolving the original issue of this thread

[STATUS]

75f Series ecus are definitely sorted via your global Tp FIX, cheers!!!

[Matt]

Are you using the 75F0F feature pack image (these are european model) in a 74F00 (Jap model) ECU? So the 74F0F still has the same issue?

What I've been advising now is to:

1. TIM (Total injection multiplier) to adjust injector resize (done automatically in the software)

2. Adjust K constant such that the vehicle traces TP within the factory load scales (after changing MAF). Don't change factory load scales during tuning

3. Any adjustment to K constant (which affects fueling), trim fueling back to normal using TIM. For example if you needed to add 20% more load with K, then decrease TIM by 20% to get fueling back to normal

[STATUS]

finger slip sorry 74f.

Also addressed the thermo fan switching point the customer had been chasing for some time too, so one happy customer!!

[Matt]

Good stuff. I was thinking that using TP within the normal factory range should fix a few issues like closed loop etc. I had noticed it on my S14 when moving TP out its normal range (when adjusting K for injectors)

[gsportcars]

I'm having this exact issue with an EDM 83f03 ecu at the minute.
I have read through this thread and the other thread also regarding this issue and downloaded the FP1 pack in an attempt to resolve the issue.
I am not sure if there is something I am doing wrong or if the additional rom doesn't suit my application.

When I open Nistune I...

Select vehicle.....s14a sr20det 80FXX, 82FXX, 83FXX

Open main ECU image... I have installed FP1 so I now see 2 additional rom files in the folder for S14A_SR20DET. One is a JDM 80F0F with _FP_maps and then another ADM 83F0F with _FP_maps also.
I don't see one for EDM. Ive tried both the ADM and JDM and I get the warning messages saying ECU Image/Address file mismatch..... .... ....Auto load address file?
I click on yes and get the extra maps to adjust. If I click no I just get the basic maps with no TIM to adjust.
I then select operations, change MAF and select z32 (adjust TP load scalars greyed out now as I would expect).
I start the car (doesn't want to run as it's probably silly rich) but when I open the TIM the current value is 512 so basically impossible to reduce the figure.

Now I realise that this is all most likely because the code in the ADM and JDM _FP_maps doesn't suit this EDM ECU but I am not sure what I can do if anything to sort this problem.

Is there a way to import the EDM bin while still keeping the _FP_maps? ... or vice versa?
Or is it the case that an EDM _FP_map would have to be written and made available to download?
Or am I way off the mark here lol?

[Matt]

EDM model is not 83F03 (I think you are referring to 82F03?)

ADM = 83fxx
EDM = 82Fxx

This might be your first point of confusion...?

There is no feature pack support for the S14A SR20DET for EDM model at this time (there had not been a request for one yet, and there are so many different Nissan variants!!)

Also it seems you are trying to use ADM maps (with 83Fxx part number) with EDM programmed ECU (82Fxx part number). That is why you get a mismatch... it wont work

When using the feature pack, you need to read the documentation firstly. Start reading from here:
viewtopic.php?f=12&t=2874

I've had a quick look at the EDM S14 code and it looks the same as the JDM S14 code. So I've patched this and attached the ENT file (to program in your Type 4 board) and the FP_maps.bin file which you copy into your Nistune ROM_Pack\Type34\S14A_SR20DET folder

Once the board is reprogrammed, connect to the ECU and sync the maps. It will pick up the ...FP_maps.bin file you copied in the ROM pack folder and all should be good

Details in the above mentioned thread about reprogramming the board for feature pack

[gsportcars]

Hi Matt,

Yeah sorry I did mean to write 82fxx instead of 83fxx.

That's good news about the jdm/edm compatability, unfortunately what I forgot to mention was that this particular car is running an odd/even daughter board. After reading the link you posted I see that the feature pack won't work in this case. I'm assuming then if I simply uploaded the edm_fp_map to the eeproms/emulators that the ecu wouldn't operate as desired even though the software may still show the new maps?

So it seems I'll have to find another solution here. Either upgrade to a Nistune board or find a way to mask the issue. I see some replies in this thread stating methods to fool the ecu into full time open loop which may be the best option.

[Matt]

The way Nissan tuned the ECUs when moving K constant for different injectors was to rescale all the TP values in the ECU to suit the new scaling (which would then fix this holding in closed loop issue)

Previously the way we tuned we only adjusted the available scales, such as fuel TP and timing TP. However other things like VCT control (TP value), knock feedback and O2 feedback TP parameters also need adjusting. Not all of these have been identified and listed in the software yet

It is easier from a tuning perspective to add a new parameter in to avoid shifting all the factory TP scales around than to change each TP related value

To use the new firmware you would of course need a nistune board