jdmae92

iTrader: (1)

I am working on my 1990 Miata project. I swapped in an 04 Mazdaspeed Miata engine running on the CAS and 1.6L sensors. I have an Innovate MTX-L wideband. I finally got it to the point where I can start it. It starts and runs fine for 5-10 seconds then dies every time. It always runs for the same amount of time, it usually restarts right away. The MAP goes to the extreme end of the gauge and the engine dies.

The wideband is wired into a switched 12v wire but it is not on while cranking.


I don't have a copy of the .msq file on this computer but it is the base 9093MSPNP file with the dwell settings for the coil changed to the MSM specs and req_fuel changed for the 1.8 and MSM injectors.

Any ideas of what to look for next?

jtpaintballwdp

iTrader: (14)

I just had a similar issue with my DIYPNP on my '92 as soon as the start up enrichment were done, it was going super lean and dying. Upping the Req. Fuel solve this issue.

I don't know if this is your issue but it might be a place to start.

jdmae92

iTrader: (1)

I reloaded the firmware and it has the same problem.

MAP goes from 80-81kpa to the maximum (232kpa?) and it dies. After starting it a couple times the MAP stays at 232 and it won't start. Sometimes is jumps back to 81 and the engine catches but then it goes back to 232 and just cranks over.

Here is a copy of the .msq.

Braineack

iTrader: (62)

and it's setup for a 2.5bar, not 4 bar sensor?


232kpa is like 17psi of boost.

jdmae92

iTrader: (1)

Yes, it is set up for 2.5 bar. I'm not sure if it was exactly 232kpa, but it was definitely at the upper limit of the gauge in MegaTune. The same thing happened when I tried the MSPNP on the stock 1.6L before swapping engines. Could the MAP sensor be bad or maybe need resoldered?

Techsalvager

Check which sensor it actually is in the ecu first.

jdmae92

iTrader: (1)

Just checked the sensor, it is 2.5 bar.

jdmae92

iTrader: (1)

Datalogs

Braineack

iTrader: (62)

theyce been know to go bad form time to time, mostly right after winter. i think a lot of times condensation makes it way into the sensor and freezes and screws it up.

jdmae92

iTrader: (1)

When I change the afterstart enrichment settings under fixed MAP mode it will run until it returns to normal MAP mode. I changed the fixed MAP time period to 30 seconds at 80kpa and it ran until it that time period was up and then it dropped to 12kpa and died. It is idling around 9.8-10:1 according to the wideband.

hornetball

iTrader: (4)

That's pretty good confirmation. Need to repair the MS.

Braineack

iTrader: (62)

Replace the sensor and see what happpens. Stupid cheap ihave like 20 spares.

jdmae92

iTrader: (1)

Put a new sensor on today. It started right up and runs fine.