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- - ms3x na 1.6 wont start (https://www.miataturbo.net/megasquirt-18/ms3x-na-1-6-wont-start-93343/)

Quote:

Originally Posted by hector (Post 1417686)

22.4% oxygen is what's in the atmosphere which means you did not have a combustion cycle. Since the engine is running I think you can assume the o2 readings are incorrect. About the leanest an engine will "run" is 18 AFR.

If the MTXL came with the same sensor as delivered with my Innovate LC2 I would wager it is not a legitimate Bosch 17025 and it is no good after a couple of initial runs. I got two of the Innovate sensors before buying a known Bosch sensor and all my troubles went away. What was happening to me was it would start up reading correctly and after a short drive start going slowly lean until it was just stuck on 22 AFR.

mine ended up being the 4.2 not the 4.9

data log . i guess new plugs are in order. also, the car still seems to be backfiring but from the intake. i redid timing and had someone verify all. its set. i did change my alternator to a 97' crank pulley to a 00' and h2o pump to 00'. i couldnt find a long nose crank pulley so why not :) set at 10* from stock ecu. and i also have the bmw vtps if that makes a difference.

Found the issue!!!
ended up being that my car is a California emissions and has sequential wiring from the get go. I wired mine up as if it didn't.
Added the two extra wires on the Ms3x 2Z2Y and tuned the ve tables and auto tuned. So runs great now and with pooowwwaaa.
also afr's are reading slightly different. Maybe .3/.4 off from ms to wideband