i insalled a fuel gauge tonight... teed it off the line going from the fuel filter to the fuel rail. my pressures at idle are 45psi and 50-55psi with the vac line to the stock fpr pinched. i think there is a small fuel leak at the banjo nut on the fuel rail, but it is hard to tell. i'm not going to drive the car until i'm sure there's no leak, so i don't know what the pressures are when boosting.

what would the symptoms, besides the smell and the actual presence of fuel, of a fuel leak be? higher, or lower pressure at idle? the banjo bolt did not seem to seat very well, but that may be just because it's rotated 180 from where honda meant it to be (because of the supercharger sitting on the intake manifold.)

thanks in advance to any helpful souls out there.

 

well, i did tape the threads on the fuel rail. the tee uses barb fittings, so no tape there, just hose clamps. if there is a leak, it's coming from the fuel rail for sure. the sealing nut over the banjo bolt threaded "evenly," but it didn't go down as far as i wanted it to before torquing out.

what i did not do, however, was replace the crush washer on top of the banjo bolt. does that thing really need to replaced every time you unscrew the sealing nut?

 

new crush washer, more torque, no leak.

my fuel pressure is at FIFTY psi at idle... which is way high
according to honda (30-37psi with the stock fpr plugged in,
40-47 with the vac line disconnected).

should i be worried about a kinked line somewhere? the
underhood gauge read 45psi when connected to the exact
same fitting.

 

nooooo the 50psi reading is with everything plugged in properly. if i pull the vacuum line on the stock fpr, and clamp the hose, it goes up another 5-10psi!

i haven't actually DRIVEN the car yet, but it idles just as it always did, holds whatever rpm i give it, etc. are you saying that it's gonna stall out on me as soon as some load gets on the motor? 50psi isn't all that much higher than the 37 honda says is correct.

still, wtf? i don't see why it should be any higher, since the jr afpr doesn't do anything at all unless there's some boost going on.

 

unless installing the gauge changed things significantly (which i suppose is possible if the tee fitting is crappy) then i don't think i'm running too rich. my a/f gauge sticks very consistently just a few bars into rich during prolonged runs all the way up to redline.

doesn't the JR AFPR do *nothing* unless it sees a pound of boost? i don't think the stock FPR is adjustable at all. the helms just says "replace it" if it is not behaving as it should (which mine seems to be - which i pull the vacuum line and pinch it, pressure goes up.)

so, i suppose i could have kinked something or clogged something during the install, but it *looks* fine!

how very worrisome.

 

nope, i didn't do anything! i have adjusted, on numerous occasions, the jackson racing fpr, first to combat tip-in leaning, and then to get back the performance i lost when i richened it up tooooo much. i have never touched the oem fpr, except to pull of the vacuum hose for testing. according to the helms manual, i should be seeing 30-37 psi with the fpr "plugged in", and 40-47 psi with the vacuum hose to the fpr disconnected. with the underhood gauge, i was seeing 45psi plugged in, and 52psi unplugged. the cockpit gauge is telling me 50psi plugged in. i have seen posts from other prelude owners w/jrsc in which they speak of 70psi idle pressures, which just confuses the hell out of me. how can that be?

so, unless the jackson racing fpr is affecting the fuel pressure at idle (which it should not be!) then it *should* be 30-37psi. do you know offhand if the stock honda fpr is adjustable or not? there is nothing in the helms about "adjusting" fuel pressure.

i suppose i should go drive it.

thanks for the help, i'm not really retarded, though it may seem that way to you.

 

well, i guess this leaves me at one of two places :

1. the gauge is not very accurate
2. something is kinked or block, causing pressure to be too high (since there's no
way it could've been "adjusted" at idle.
3. the JR FPR is fubar'd and is messing with teh pressure when it shouldn't be.

check this post out : <A HREF="http://www.preludeonline.com/showthread.php?s=53b1b3e147737b35bb1862c33498ba60& postid=272581#post272581
" TARGET="_blank">http://www.preludeonline.com/showthr...581#post272581
</a>

is there some other pressure this dude is talking about, because i don't see how he could've been 100+ at idle if what you're saying is true!

 

hmm, why is this so confusing?? at least, i'm confused! first JR tells me that the stock FPR is not adjustable (which it isn't) and that their "AFPR" does nothing at idle. then they tell me that because of tip-in leaning, etc, the idle pressure should be higher (50-60psi) than the helms specifies.... so how do they acheive that? is there in fact some other point of adjustment for the fuel pressure?

i did drive the car. there are no fuel leaks, but it's not running right. pressure goes from 50psi to about 85 during boost, which is actually exactly what JR thinks it should be!

the good news is, no leaks. so perhaps there's nothing wrong except some connection the came loose in the vacuum system or something. i also got some new fittings that look cleaner than the shoddy T i used... will try it tonight.


[Modified by schwett, 10:53 AM 8/30/2001]

 

at idle it occasionally hops around madly, but the one spot it decides to sit in is a couple bars rich. maybe 3 or 4. at WOT, it is very steady and stable in the exact same spot. while cruising, in closed loop, it oscillate back and forth between very lean and slightly rich, which i gather is normal.

my pressures were *really* high before i installed the gauges (i turned the jr afpr way down about a week ago), so my plugs were fouled already. i put new ones in about a week ago too. it made a big difference.

also, i finally got a better answer from JR about their afpr. the original statement that it "does nothing until is sees a pound of boost" is not really true. it *DOES* set a baseline pressure at idle, and then when it sees boost it starts increasing the pressure at some rate. i guess the single set screw on it controls either the baseline only or both the baseline and the rising rate. need to experiment a bit.

according to jackson racing, the pressures i'm seeing (50 / 85) are absolutely correct. 50psi at idle... man, i never woulda thought.

in any case, i got some new fittings and am going to replumb it tonight. something is definitely wrong, but it may be completely unrelated.