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-   -   MSPNP2 1990 sequential fuel injection question (https://www.miataturbo.net/mspnp-55/mspnp2-1990-sequential-fuel-injection-question-96694/)

Carrera95 Apr 15, 2018 07:11 PM

MSPNP2 1990 sequential fuel injection question
 
I have a 90-93 mspnp2 for a 1990 miata that i just installed 640cc injectors and modifed the wiring to go sequential. I unpaired the injectors and ran injector 3 to injector C in the options plug and inj 4 to inj D and changed the settings in tunerstudio. The car seems to run fine after adjusting the tables for the new injectors but i read that there are jumpers which need to be changed but im wondering if this is the case or not. Thanks for any help!

Matt Cramer Apr 18, 2018 09:26 AM

MSPNPs are normally jumpered for sequential injection from the factory.

Note that the injector outputs run in alphabetical order, so on a Miata firing order, A goes to cylinder 1, B to cylinder 3, etc.

Carrera95 Apr 18, 2018 10:38 AM

Thanks for the response! When i open the mspnp i dont have any jumpers on the seq pins, is this ready for sequential like that? Also from what i understand i have it wired A to 1, B to 2, C to 3, D to 4 so i need to change that to A to 1, B to 3, C to 2 and D to 4 correct? Thanks for the help :)

Matt Cramer Apr 20, 2018 09:14 AM

Can you post a picture of what you've got with the jumpers? The current default is to build them with sequential jumpers, but it's possible you have something that's been altered or was from a point they were built differently.

Carrera95 Apr 20, 2018 09:49 AM

I will when i get a chance tonight but i think it might be ok, last time i checked its a v1.5 board if that helps. I changed the injector wiring to match the 1342 firing order and it seems much better now.


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