Help! Oscillating 4k idle after startup??
 

Hey guys, so yes i am new to megasquirt but need some help. I bought a flying miata turboed miata running megasquirt 2 pnp. I drove the car home 8 hours with no issues. No problems with the car at all.

the car was a black interior swapped nb 1999 but the dash was still tan. I swapped to a black dash to fix this. The things i did during this was:

1)Riveted on stock ecu brackets so i could mount megasquirt in the stock location.

2)i had to cut one wire (ground) because it was wrapped around the dash frame but was reconnected.

3)unplugged all the normal wires to the dash and under the steering column in order for the column to be dropped and the dash removed.

all dash guts were swapped between the old and new dash so all controls and wiring are the same.


So after i got everything back together and plugged in, the car starts fine but immediatly goes to 4k rpm and starts to jump between 3.5k-4k rpm. It had a normal idle before the dash swap.

I tried to find a vacuum leak but all seems well. I didnt touch any wiring to do with the ecu so im not sure what could be causing it? All wires into the ecu seem fine none are loose. Nothing mechanically was touched, just the dash was swapped.

A datalog should make the issue obvious. Any response without looking at one is going to be a shot in the dark.

Ive got a cable on the way but right now have no way to connect to the ecu. Since i didnt change anything software related, it had to be something with wiring. Just wanted to see if there is a common known problem that causes this that i could check in the meantime.

Did you reconnect the MAP line to the ECU itself? I am reading stuff about wires, but not the line being reconnected

Yes i did. And i went through the line from ecu to manifold and there are no cuts or leaks.

What happens if you run the idle valve test, and ramp it from closed to open? does it change at all.

Personally, I would double check the manifold, as that high of an RPM sounds like a uncapped port for it to get to 3-4k