Quote:
Originally Posted by psalt
Open loop mixture with the ECU pulsing the FV at the default(s) is rich. When the ECU, fuse or relay fails, the default mixture is lean because of the blocked FV, allowing no lower chamber pressure bleed off. The engine still runs, evidenced by the countless poor driveability questions. On the EFI car, the engine dies with the ECU.
.
|
that makes sense. it would pulse greater than 50% to make it rich once it goes open loop?
can you look at it 2 ways, either the O2 leans out the open loop mode, or the open loop mode richens it for high RPM or higher load demands.(?)
so for those that dont use the O2, the only thing making it run richer for hi load demands is the shape of the funnel, which may not be enough unless it is overly rich at idle. (?)