So i'm having quite the issue, i adjusted my TPS and the works to have the car idle at a rock-steady 900rpm ( it has a "race" port, etc ), i have a Power FC, RX7store ultimate fuel system, walbro 255, 550cc primaries and 1600cc secondaries, etc etc, anyways, when i was adjusting my fuel pressure it began at approx 30psi and i was adjusting to 35psi, if i would go any higher the fuel pressure guage would start wigging out on me and start bouncing all over the place....

i have an aeromotive FPR i believe it's a 1:1 rising rate, any idea why it started getting all weird?, it wont go any higher then around 40psi no matter what i do....

also, it's smoking on idle pretty bad and running real rich, i just re-connected the O2 sensor but i doubt that makes any difference, any idea why it would be puffing black?, everything else was adjusted or changed that i can think of, i havent swapped the fuel filter yet since my brother's honda is sitting on the jack stands ( ironic! ), anyways, any help and points in the right direction will be greatly appreciated!...

 

Did your adjust fuel to compensate for the higher fuel pressure?

 

yeah i have, i adjusted the injector mapping, it used to read all 100's, i ended up tuning it down a fair bit around where it idles and still no luck....

 

nothing!?..

 

Where you adjusting the fuel pressure with the vac source connected or disconnected from the FPR?

 

i've noticed that when you set the aeromotive a1000 FPR to a certain pressure at idle with the vac hose disconnected (in order to get the total pressure difference added), it'll settle down consistantly 1-2 psi away from where you originally set it, so getting it right is slightly trial and error. However, besides that small quirk, I've had no problems with it (also using a walboro 255 and 550's/1000's). the port on the bottom is the return to the tank, and the ones on the sides are from the fuel rails (or just plug one), make sure this is hooked up correctly. Its possible that if your vac line is hooked up, at idle and above 30 psi, the pressure differential is pushing some fuel thru a small tear or something in the diaphram or seal, and that fuel is getting sucked into the engine thru the vac line, so try disconnecting the vac line and seeing if theres any gas in it.

 

sorry guys, i was adjusting it without the vac source, also, which vac source is the best to use for the FPR?...

thanx for the advice guys, i'll try it out tommorow!...

 

ok so here's the deal, if your looking at the FPR the end on the right hand side is blocked off which i believe is right, the other goes to the tank....

however, i just noticed there was NO VAC SOURCE fed to the FPR, so i put a line from the front of the intake manifold as instructed by RX7 store and on a WOT rev i get 40psi, however if i try and adjust the idle at most i can get is 32psi, if i try to get anymore out of it the guage starts wonking out on me and bounces everywhere, when i rev the pressure rises unless it ends up bogging when i rev then the pressure drops, but on a light rev throughout the RPM band it revvs fine and pressure raises accordingly....

any other idea's guys?, what vac source should i use for the FPR?, is the one off the front of my upper manifold sufficient?...