Fuel Pressure Regulator

[LunaTech]

I just installed a fuel regulator in my mp3. Now the car hesitates when I start it. Can anyone help me fix this problem?

 

[LunaTech]

Oh yeah! I also need to know the psi on the stock fuel regulator and what psi I should set the new one to.

 

[1sty]

stock fuel at idle is 36-40 PSI although my car is lower for some reason. Why the FPR?

 

[LunaTech]

I got an CAI for the car. Someone told me that the more air the car gets, the more fuel the engine should get too to get a better air/fuel mixture. Don't know if it's true so I decided to check it out for myself. Don't know too much about the subject, but it seemed to have given the car somewhat of a better performance. Thanks for the reply by the way.

 

[1sty]

FOr just the intake th efpr is totaly useless from the knowledge I have gathered from this site. The Protege compute has an insane amount of autority and can more then compensate the car with more fuel need with the added air. The FPR is most useful on turbo cars and is actualy no that effective on protege turbos becuase the ecu fights it.

 

[LunaTech]

Thanks for the info bro.

 

[70]

Yep, for just an intake you don't need to mess with the fuel. The stock ECU has more than enough range to deal with the small amount of added air from the intake.

 

[chdesign]

Granted the FPR won't do much in open loop but it can get rid of that nasty overly rich situation in closed loop the reason why i will be installing one. Lower the fuel pressure adn bam you've pulled some more power when your car is in closed loop....also in that closed loop is where I will need to fine tune anyways with my NA setup.

 

[70]

Granted the FPR won't do much in open loop but it can get rid of that nasty overly rich situation in closed loop the reason why i will be installing one. Lower the fuel pressure adn bam you've pulled some more power when your car is in closed loop....also in that closed loop is where I will need to fine tune anyways with my NA setup.

Flyin' Miata is working on that situation, the ECU will probably still over ride that.

Remember, the ECU has insane control over the fuel, being able to put in and pull out a lot if needed to see what it wants to see, regardless of the FPR.

 

[blynzoo]

Granted the FPR won't do much in open loop but it can get rid of that nasty overly rich situation in closed loop the reason why i will be installing one. Lower the fuel pressure adn bam you've pulled some more power when your car is in closed loop....also in that closed loop is where I will need to fine tune anyways with my NA setup.

I could be mistaken, but I thought that the car was too rich at WOT (open loop), and better at closed loop.

It's the set maps of open loop that make it run rich.

 

[slowyellowp5]

You're not alone Blynzoo that's what I thought too...isn't there a whole thread on the WOT problem?

 

[chdesign]

no in open loop it keeps it pretty well in stoch. in closed loop though it goes way rich hence the overly rich situation we get over 4 grand and at WOT

 

[saided18]

No i think your wrong man.

OPEN loops means that the ECU is reading all the sensors hence the name open loop b/c the ECU "opens" the loop to read external things.

CLOSED loop means the ECU closes off itself to all most everything and just spits out a constant amount of fuel.

This is what Keith said from FM and i think he knows what he is talking about.

I know it goes against the normal electric labels which says that open loop means the curcuit has break in it. (ie a switch is in the "off" position) and Closed loop means that the curcuit is complete and current is traveling threw the curcuit. (ie the switch is in the "on" postions.

 

[chdesign]

I know that open loop it reads the sensors which is why it keeps it stoch. but in closed loop it doesn't thus it goes by predetermined fuel maps for saftey of the engine that make it run rich as crap

 

[bill]

I know that open loop it reads the sensors which is why it keeps it stoch. but in closed loop it doesn't thus it goes by predetermined fuel maps for saftey of the engine that make it run rich as crap

Got it backwards- the sensors provide feedback to computer in closed loop (like a closed circuit). Open loop (like an open circuit) sensor feedback is ignored by computer.

HTH,
Bill

 

[saided18]

I don't know buddy. but Keith at FM told all of us that closed loop is when the ECU ignores most of the senors. and open loop means the ECU read all senors. So i think Keith at FM KNOWS what he is talking about. unless your calling keith a lier??

 

[chdesign]

OK well whatever the FPR will help int eh mode where it doesn't read the sensors. And I'm not calling Keith a liar thank you very much I just had my facts backwards sorry

 

[saided18]

hey chdesign. my post wasn't directed to you. sorry. it was for the guy that posted before me. I think he is screen name is bill.

 

[chdesign]

my head starts to go in circles when i read this thread lol open loop closed loop sphere loop, backwards loop, screwy loop.....who really knows anymore lets just say the FPR will help when teh ECU ignors input and somethign like a S-AFC will help when it reads inputs.

 

[saided18]

what is a S-AFC???