[Tyler16]

I'm looking for clarification about fuel pressure and being lean or rich. Is it true that the higher you set your fuel pressure the leaner the engine becomes? In the same sense that if you put a crease in a garden hose and the crease is the "regulator" the pressure is higher before the regulator and thus letting out less water out of the hose.

Thanks.

 

[squekster]

I'm looking for clarification about fuel pressure and being lean or rich. Is it true that the higher you set your fuel pressure the leaner the engine becomes? In the same sense that if you put a crease in a garden hose and the crease is the "regulator" the pressure is higher before the regulator and thus letting out less water out of the hose.

Thanks.

The injectors require a min pressure to operate
properly. If you increase fuel pressure you are
forcing more gas thru the injector when it is pulsed.
If you lower fuel pressure less gas is being forced
thru the injector with each pulse resulting in a
little bit leaner burn.

 

[Tyler16]

The reason I ask is because my car failed emissions because CO% was too high. My friend lowered my fuel pressure from 45 to 36 and it passed with flying colors. So I don't get it. Is the car rich or lean.

The test shows the standard should be 1.2. It failed at 2.21. Then after lowering the pressure it passed at .10

 

[Tyler16]

I think I just answered my own question. If CO% was high then your right, lowering the pressure decreases fuel which lowered the CO%.