What should my fuel pressure be while idling? What should it jump to when you give it gas?

Mines 30 at idle and 35 when it has gas. According to my a/f gauge its running "rich". Is this correct?

Mike

 

what motor is this. does it have any mods.

 

its a jdm b16a with intake, exhaust, and underive pulley, and a kenji chipped p28 ecu

 

if u have an autometer guage, its a POS, just good for flashy lights [except at WOT in some cases] it seems kinda low. y8 on boost with stock fpr with guage its 38idle and 42wot

 

i have a autozone fpr gauge....im pretty sure its not accurate. the only reason i know my fuel pressure is bc i have an actual gauge inside my bay with a needle and ****. thats how i know its at 30 at idle and around 35 when its getting gas

 

bump, sometimes its hard getting answers around here

 

next day bump

 

have u checked for vacuum leaks? it seems low

 

ya, i have. i have a adjustable fpr so i could bring it up if i needed too

 

Im new, but as far as i know, your fp should be right around 40, mine is set at 48 but thats for other reasons... if i were you i would consider bringing it up to 40 to stay safe.. its better to run rich than lean

 

When you look at your gauge, are you doing so with the vacuum line off the fpr to simulate wide open throttle?

What it reads with the vacuum on is not what you need to look at, 38-41 or so with vacuum off and a stable idle is what you need to shoot for.

 

unless yuo have a wideband o2, i wouldnt trust your air/fuel gauge if my life depended on it. theyre worthless, just like underdrive pulleys, all those do is screw up your engine in the long run by letting the shaft vibrate too much.

as to your question, it should be at 31-38psi with the vacuum hose attached and 40-47psi with the hose disconnected according to haynes. this is for a d-series but as far as i can remember, its the exact same, i have mine at 40 with hose attached.

 

yeah, 38 idle is good and 42-44 at WOT

 

nobody can answer this question, especially with a chipped ecu. theres no telling if its a rich tune, or lean tune. either way, if you are having some kind of problem i garentee its not fuel pressure related. also, the ecu will adjust injector pulse to correct a/f to within 5%. adjusting the fuel pressure manually to such a little degree wont change a/f hardly at all because if you set it high, the ecu will see the rich condition and shorten the injector pulse as much as needed to correct the problem.... within the 5%. hope that helps. basically, without having a wideband you have no clue what it should be set at nor does anybody else.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by schardbody &raquo;</TD></TR><TR><TD CLASS="quote">nobody can answer this question, especially with a chipped ecu. theres no telling if its a rich tune, or lean tune. either way, if you are having some kind of problem i garentee its not fuel pressure related. also, the ecu will adjust injector pulse to correct a/f to within 5%. adjusting the fuel pressure manually to such a little degree wont change a/f hardly at all because if you set it high, the ecu will see the rich condition and shorten the injector pulse as much as needed to correct the problem.... within the 5%. hope that helps. basically, without having a wideband you have no clue what it should be set at nor does anybody else.</TD></TR></TABLE>

1) yes we can answer this, according to haynes and chiltons we can at least

2) no one said anything about it being tuned, just chipped

3) how can you guarnatee anything, you already said no one can answer this question

4) we already stated that the a/f guage was useless without a wideband

5) and once again, we do have a clue since it hasnt been tuned and that would mean factory specs are best since he doesnt have boost

 

dude, that makes no sense. basically, if we are talking about a stock motor, ecu etc. then stock fuel pressure is correct. since the B16 isnt stock nor is the ecu, how can you say what the fuel pressure should be set at. we can give him a baseline based on a stock setup. but he wasnt asking for stock parameters, he is asking for "his" setup. therefore, any answer could be the correct one, but who knows without a wideband to tune it.

 

which was already said previously, but without knowing, usually the factory settings are the best specially since basic bolt-ons dont require much more fuel if any at all. only thing that would really need it is the chip but without it being tuned, stock is the way to go. now if he were boosting, i wouldnt be saying to stick with stock, id say get it tuned. but with bolt-ons and a chip that hasnt been tuned, id stick with stock.

 

sure, i would too, what i was saying is fuel pressure isnt an issue in his case w/out knowing the tune of the chip theres no reason to change it. thats all i meant.

 

i need to be tuned, bottom line. im just trying to run normal until i can get that done.

Mike

 

ok, then like i said 31-38psi until you can get it tuned, id stick around th 38 end of that range. thats also with the hose CONNECTED.