6pak72 New Reader
Aug. 13, 2013 7:30 a.m.

Swapped a 1.8L '96 engine into a '92 Miata about a year ago. Tuned via MS2. Using the 1.6 throttle body.

Runs great once it gets warm, stalls and hard starts when cold. Also, cannot loop the AFR readings back into the Data system from the ECU, the car stalls immediately until it warms up.

I've been told the problem is related to going from open loop to closed loop.

Any suggestions to solve this?

EvanB PowerDork
Aug. 13, 2013 7:38 a.m.

Why are you using the 1.6 throttle body?

Have you looked at the warmup enrichment settings? What what AFR is it reading while cold/warming up?

KazeSpec New Reader
Aug. 13, 2013 9:53 a.m.

He needs to use the 1.6 TB unless he wants to wire up a 1.8 TPS to his factory harness. 1.6 TPS is an open/closed switch while the 1.8 TPS is variable.

EvanB PowerDork
Aug. 13, 2013 9:54 a.m.

But he is using megasquirt, not the factory computer...

Just curious. I don't even have the TPS hooked up on my Miata.

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