Hello all, I own a 92 1.6 naturally aspirated Miata with MS2pnp, Flowforce 640cc injectors and a Walbro 255 pump, stock ignition. Since the car is a 1.6 and comes stock with batch fire injection, I decided to convert to sequential injection. After a days worth of research, I cut back my stock injector harness, snipped the yellow/black wire from the 2nd and 4th injector connectors, and connected them to the options connector for the megasquirt. inj. 2 to pin 26 (inj D output) and inj. 4 to pin 18 (inj C output). After buttoning everything up, I pulled up TunerStudio and changed from untimed to semi/sequential injection. After starting the car I noticed it seemed to be running rough. I used a stethoscope to verify all 4 injectors are firing and checked spark just to be sure. But still the engine idles rough almost like it’s running on 3 cylinders, I drove around the neighborhood and noticed an extreme lack of power as well. I am at a loss and do not no what else to check besides voltage at the injectors. I have had no issues prior to attempting this mod. Any input would be appreciated, I spent a few hours online verifying my work and I do not think my wiring or megasquirt settings are to fault. The fuel injectors and fuel pump are very new as well as the megasquirt itself.

 

How do the AFRs look? You'll need to retune after a change like that.

 

Afrs are lean, idle rolls a bit like 100rpms, I had to add quite a bit of fuel to idle and free rev range. I thought maybe the lean condition was cause for engine running so rough but even with idle fluctuating between 14.7-15 the engine sounds as if it’s a subaru😂

 

do you need this?

https://www.diyautotune.com/product/...injection-kit/

 

To my knowledge, I do not need that add on, my ECU unit came with a 26 pin options connector and this is what I am using for the 2 additional drivers

 

do you need to move a jumper then? I'm running the MS3PNP and have to move two jumpers.

 

https://www.miataturbo.net/mspnp-55/...rk-cops-85122/

 

MegaSquirtPNP by DIYAutoTune.com

MegaSquirtPNP by DIYAutoTune.com

these are two of the articles I referenced when researching this mod, I have the MS2pnp 1.3 main board. I only see jumpers needing to be moved in the MSPro unit which I do not have, I was thinking maybe having a problem with the fuel injectors or pump but it seems unlikely as these are so new. I know there is a test mode for the injectors in tuner studio but I am unfamiliar with the process

 

Test mode is super easy to use. Do it.




Click enable test mode, and use settings like the above in injector testing. Then cycle through each injector channel. You should be able to hear each one, and which position it's in.

 

@nigelt thank you so much I will try that feature as soon as possible