fuel consumption...

[Audi180]

well, i've checked it up a bit...drove in an open road, 5'th, about 2.5krpm, 15:1 a/f ratio

and i've got 9.5MPG

i don't know whats wrong, i have the haltech E11... mafless setup, lean a/f ratio, new spark plugs - greddy iridium 8...

what else could be wrong?

thanks...

Tom

[Shocker]

try a nismo FPReg thats for sure your problem! i get around25-28 mph on the freeway crusing at 70mph with my 25.. that number goes considerably down once i start boosting it.. haha

[Audi180]

you think that my fuel pressure is too high?

i'm using a stock fpr....

[Darius]

Since you have an aftermarket fuel pump, you should probably have an adjustable fuel pressure regulator with gauge to verify your fuel pressure setting.

[300Plus]

Since you have an aftermarket fuel pump, you should probably have an adjustable fuel pressure regulator with gauge to verify your fuel pressure setting.

+1

[Shocker]

lol you definitally need a nismo adjustable fuel pressure reg.. set that to 43 psi ish with vac line off.. your motor will be much more responsive and your gas mileage will dramatically improve.

[gawdzilla]

why does the fuel press matter so much in this case? i'm not saying having the wrong fuel pressure by using the stock regulator w/ a big pump is a good thing, but i dont see how adding an adjustable fpr will solve his issue at hand.

setting the fuel pressure to stock numbers just lets your stock injectors w/ stock opening times dispense a stock amount of fuel. if he was using a stock ecu and the pressure was wrong, he would be running rich and wasting fuel. If he has a wideband and an EMS, it is telling him how much fuel he is consuming, and the rest should be returning back to his tank.
Modified by gawdzilla at 11:24 AM 5/16/2006

[Darius]

I'm not saying that this is the root of his problem, but since he does have a larger fuel pump, a fuel pressure gauge coupled with an adjustable fuel pressure regulator could eliminate a possible fuel pressure problem.

Sounds like the haltech is misreading too much air into the system and trying to compensate with fuel. I'm assuming you're running a MAP setup then?

haha this was my 420th post

[Shocker]

good point gawd.. i didnt really read his initial post well enough to see hes getting 15:1 A/F, that just doesnt add up to your gas mileage tho, i mean thats at 2.5 k rpm thats hardly touching boost.. assuming your still stock twins.. my guess is the wideband could be reading wrong, what kinda ratios are you getting while under boost in higher RPM's

[Audi180]

i'm getting 11.5:1 at wot... and yeah still have those stock turboes...

will is right tho.. that's the reason i wrote everything down...

i'll get that fpr anyways...

but what else should i consider?

[Darius]

Did this just happen out of the blue or was it after you installed or tuned something?

[Audi180]

yeah, it happened after i've installed the RB :-)

[ItzGenX]

That seems a crazy bit off. At 15:1 you should be seeing at least 28mpg. Either your wideband has fallen out of calibration, your exhaust has a leak before the sensor, or you are misfiring (a miss will come up as lean). A FPR will not fix your issue with an E11. Your timing could also be too advanced or retarded, wasting combustion energy at cruise. You should be around 28-32 degrees btdc at around 2.5k and cruising depending on load conditions.

[silent dave]

i'll take another shot at it. could you be running too rich and fouling plugs causing poor spark and not getting a good enough burn to get a correct AFR? have you pulled your plugs recently?

[gawdzilla]

wouldn't that make his AFR read rich?

I agree w/ genX. either an exhaust leak, wideband out of spec, or timing is way off and just not making power

[silent dave]

a wideband can't sense unburnt fuel. an incomplete burn results in a incorrect lean reading.

[Audi180]

i have an upgraded ignition system...

aem igniter, splitfire coilpacks and greddy racing (8) spark plugs...

i don't feel any missfires...

my ignition timing is set by the base map i got with my e11... it should be fine...

[Bluefire]

Maybe you should try running some 7's or 6's for spark plugs. I mean your still running stock turbos... and assuming stock boost?