How do I set my Megan FPR? First start question.

[Ezzo]

As the title says, Sorry for posting in the KA-T part since this isn't specific but I figure you all use FPR's more than the other areas.

I just installed the FPR now my question comes in. What steps should I take to set my fuel pressure and What pressure reading should I be at for a stock KA24DE.

I only ask because I know that the pressure reading will differ on a warm or cold engine, and what the best way I should go about setting this.

Before the flames start of why I have an FPR on a stock KA is because my fuel pump went a few months ago and I figured since I'm going KA-T anyway I'll put in the Walbro. Since then my stock FPR gave up the ghost and in the same boat again I figure I'll just get the Megan unit.

Thanks in advance for your time and answers!

[480sx]

You need a fuel pressure gage or your just pissing in the wind. about 42-43 PSI with the car not running is where you want to be. When the cars running, your PSI will drop to about 38. I Mc-Masterd myself a sweet inline gage setup, if you want the details just ask.

Or your FPR might have a built in port for a gage, thats the best way to do it IMO, but my FPR didnt have one.

[WI_240sx]

i have similar questions about a FPR... i dont know to much about fuel delivery on KA's exept for the injectors... those are easy..

but for a gage, does it read off the incoming line or the return line... i would think the incoming line just because return would have lower psi than the rest of the lines...and another thing, is the gage put on by using a T-insert or just by simply puting the gage inbetween lines...

[neverlift]

i have similar questions about a FPR... i dont know to much about fuel delivery on KA's exept for the injectors... those are easy..

but for a gage, does it read off the incoming line or the return line... i would think the incoming line just because return would have lower psi than the rest of the lines...and another thing, is the gage put on by using a T-insert or just by simply puting the gage inbetween lines...

slow down.

fuel pressure is created by the fpr on the return line, if you read off the feed line its gonna be very low, well not very this is fi.... what the fpr does is restrict flow back to the tank, generating pressure build up in the rail.

op cold or hot shouldnt matter crank the motor and set it, 38is with vac and 43ish without(ie vac source unhooked)

[WI_240sx]

ok... thanks.. didnt know that.. would it effect anything if i had 2 gages running off the line... one in the engine bay and another on the inside of the car?

[480sx]

Just extra chances for a fuel leak. I would get a electrical sending unit to measure the FP up in the cab.

[WI_240sx]

how does that work?? like a sensor in the fuel line that sends it to a gauge in the cab by wire?

the reason i was askin about 2 guages btw is because im planning on playing around with my fuel system alot, and i dont want to hop in my car and turn the key to prime the fuel pump to read psi every time i adjust something...

[480sx]

Not really understanding what you plan on doing.. You have to change your FP from inside the engine bay soo.. Whats the big deal with making the adjustment, priming the FP, then looking at a gage inside the engine bay? I mean for safety reasons, having a fuel pressure gage is a good idea, you can monitor the health of your fuel pump and you might catch a fuel leak or something.

Fuel pressure is one of those things you set once, and keep it at that set pressure until you decide to squeeze more out of your injectors+retune the ECU.

Yea, an electric pressure sending unit + gage. Works with a sensor(sending unit) hooked into your fuel feed line after the filter but before the FPR. Wire connects the sending unit to the gage.

[WI_240sx]

yeah... ur right about all that.. didnt really think about it in that way...

im assuming you got one of these on your car?

[neverlift]

90% of the kat guys have them, I own a megan, use it with my stock injectors, seen 11psi daily for a long time, they currently see 5.5 from a t3 , but I am crazy, and have a bad *** custom tune to work it

[nissanfanatic]

I would only monitor fuel pressure in the driver's compartment via an electric gauge. Fuel should never enter the driver's compartment. I think that is banned in just about every form of legitimate racing, and for a reason.

[Ezzo]

Thanks for the help guys

I got the pressure set well. I'm not running rich anymore. but there is still a lack of power once the engine is warm. Not quite sure whats left to narrow that town.

So far i've replaced the coolant temp sensor, tryed 3 maf's, 2 ecu's, swapped the TPS, new 02 sensor.

Last things I can think of are faulty mafs wiring, knock sensor.. or maybe one of the new sensors was bad or has gone bad..

[neverlift]

are you checking any of these parts first, dont go wasting cash on parts that dont need replacing!

I'd start by checking grounds and anything my multi meter can check w/ fsm(everything...) also do a code test....

did you set the tps correctly? and re-establish timing?

scv hooked up, they were used to make more low end

[Ezzo]

Only the O2 and Coolant temp sensors were purchased, The others were all taken from my spare KA that was removed from a very well running but totaled 60k s13.

Is there a FSM scan on NICO? I'll have to check around for it.

Timing was redone by my mechanic when I went in for PA inspection and emissions.

Edit: Also no codes, Which is why I swapped the ECU with the spare I had. I had read something about it going into learning mode and pulling timing. So Incase that had happened I had a control to experiment with.

Second Edit!: Found the FSM zerothread?id=311075

Just for reference incase anyone searches this thread.