Parellel install removed MAF, good tune goes bad.
 

I've an MS-1 parellel install of fuel/spark (see sig for spec).

The MAF was still in the intake tract when I installed everything as they arn't hugely restictive like an AFM is. Well today I decided to remove it as it's redundant and hoped for slightly more power at higher RPM and nicer throttle response. I was actually greeted with a poor running car that was hard to start when hot, ran rich at cruise and any application of light throttle caused AFRs to swing quite lean.

Could it be that the OEM ECU didn't like the MAF removal even though my MS is controlling fuel/spark? I didn't have time to break out the laptop and datalog stuff, but I also noticed that AE wasn't being applied either.

I've plugged the redundant MAF back in and the engine runs smooth again with AFRs locked down to ~15:1 in vacuum.

Maybe standalone installs really are win ;)

I was running parallel for over three years without my AFM...now that I'm standalone the only difference is I don't idle well :bigtu:

What do you mean by not idling well?

What are the symptoms?

I haven't tuned it well enough with a/c on...that's about it ;)

The NBs don't run well in parallel; that was the configuration I used back when I had the MS1. Specifically, the stock ECU uses both ignition advance and the idle valve to control the idle. Control the ignition and your idle will go haywire. If your state permits it (ie OBD inspection) switch to full standalone.

Dimitris