DIY autotune

[Newkid99]

Hi guys I am new to the forum but I've done lots of research and reading on here and never made an account until now. Recently as my build slowly comes together it has come time to decide on what tuning system to use. Originally I planned on ordering an ecu from enthalpy but to have more reliability and tuning ability I wanted to go with megasquirt. I also like that I can run a map sensor instead of a z32 maf sensor. My question is if anyone has built their own from DIY autoune? Here is a link to their page:
https://www.diyautotune.com/support/tec ... our-240sx/
I was also wondering if anyone has used this on an s14 ka with the coil inside of the distributor? It seems like all of the diagrams on this page tell me it is only meant for s13 models with an external coil. Any help is appreciated.

[BigLoukaT]

short answer is yes - there have been a bunch of people that have built/bought megasquirt setups especially with the creation of the PNP kits. What version are you looking into? If the S14 has a power transducer for the coil, then any of the PNP setups on microsquirt will run it. A lot of the talk about the external coil setups were because the megasquirt would control the coil via an onboard power transducer, instead of using the stock one, however that strategy has been somewhat passed by as we can control the existing transducer.

Personally, I have built a DIYPNP with sequential injection and it is my favorite thing about my car at this point. Best decision I made and never looked back.

[Newkid99]

short answer is yes - there have been a bunch of people that have built/bought megasquirt setups especially with the creation of the PNP kits. What version are you looking into? If the S14 has a power transducer for the coil, then any of the PNP setups on microsquirt will run it. A lot of the talk about the external coil setups were because the megasquirt would control the coil via an onboard power transducer, instead of using the stock one, however that strategy has been somewhat passed by as we can control the existing transducer.

Personally, I have built a DIYPNP with sequential injection and it is my favorite thing about my car at this point. Best decision I made and never looked back.

So i bought a diy autotune msx3 kit and I have it all built but had some questions still. Is there a guide on how to do the sequential injection? Also I was pretty sure the set up for the idle valve was the 2 wire pwm but I dont know? What jumpers do I need to solder in for a ka-t? Emailing diy autotune now to ask if they can send me a list of jumpers, but I would like to do a write up once I have it done and working.

[S14ILKA]

I've got DIYPNP MS2 on my S14. Running COP. Works like a charm but wasn't super easy to make it work. Previous tuning experience and trouble shooting know how is definitely a must to make it run good.
My friend assembled it for me, he is an electrical engineer. I've tuned a lot of cars prior to this (hondata, crome, ectune, megasquirt, AEM) so I kind of know what I'm doing.

[Newkid99]

Alright soi got everything all nice and assembled, decided to get the ms3x add on. the diy autotune people have been very helpful and answered every question ive had. I got my firmware flashed but now I am struggeling to get the ms3 to run with my stim. It shows it is cranking but not firing on any injectors or sparkplugs. Updates coming soon.

[S14ILKA]

Does the SYNC light come on after cranking?

[Newkid99]

Alright my bad, i don't get emails when I have replys on this thread. I got my stim to work with my ms3, and display on the ms3x. If mods are okay with it, i'm going to try and make a sticky on how to do all of this from start to finish, I also have an ebay channel I will record everything on to make it easier to visualize. Right now I am soldering all wires to a female plug for the stock harness, which i got from disassembling a auto ecu. More info when I get the car started so I know my wiring was done correctly. If anyone has done this I still have a few questions, waiting on reply from matt @ diyautotune. If someone can answer them, please do. I'll post up answers when i get them.
1) Is pin 26 on ms3x tach out signal?
2) Does pin 14 from ms3x go to - on coil? Making it fire correct?
3)db37 bottom plug pin 36 goes to power transistor, but I do not have one because I'm running the internal coil dizzy s14. Where does 36 go to?

[Newkid99]

http://jimwolftechnology.com/wolfpdf/DI ... SISTER.PDF
Pin 7 gets 20 amp fuse and 12v switched source, pin 8 gets pin 14 from ms3x correct?

[Newkid99]

So I had a reply from diyautune, pin 36 runs to the negative on coil telling it when to fire, pin 14 on the ms3x is for when you want to up the anti to some stronger coils.