wilham320

iTrader: (1)

i hopped in my car yesterday then bam... lean for no reason- around 17-18afr.
car has been running flawlessly for over a year on same tune. only happens during light throttle / cruising at constant speed. so i floor it just to see what happens and it goes mid 11's afr to redline with 15psi boost, same as usual
i figure its just a 02... but nope still does it. grabbed the laptop to check the emanage out, all sensor read normal, emanage is correcting output map voltage like it should, and NO CEL ever.
the only thing i have notice is that injectors 1 & 2 aren't clicking has hard as 3 & 4 if i put a screw driver on the ear, i can hear them but i can't feel them just holding the handle like i can with 3 & 4 are these tied together or use the same driver in the p28? is my ecu going bad or what. can't be a ignition thing.
i'm stumped
things i did so far:
i swapped 02 (never been hacked or any thing), swapped map sensor, fuel pressure is good on filter mounted gauge 45psi, checked tps through emange- good, all plugs look identical (all were same shade of dark brown??) so i doubt it's a single injector failure, i tried messing with the tune, but always comes back.. idle afr is off a little like 15-16. checked for vac leaks sprayed carb cleaner around all gaskets-good, reset ecu... nothing


Setup
d15b stock longblock.. thick headgasket and arp's
15g greddy kit, intercooled at 15psi.
skunk2 mani, gsr tb,
255 walboro, lucas 440's, aem fuel rail, stock regulator
virgin p28 on emanage w/ greddy 3 bar; plx m300 wideband
dyno tuned by fuccarlos, fine tuned on street by me

wilham320

iTrader: (1)

bump for my broke ride

JDMFantasy2k

holy expletive you run 15 psi on a stock block d15, props to you

check the IAT sensor, i doubt that's it, but it does play a role in dictating the AF ratio. Other than that, check the 2 injectors that aren't so loud and inspect that half of the fuel rail for anything suspicious. Can you disable closed loop mode with the emanage?

Kamin

how lean are we talking?

something like 15-17's are perfectly normal on light cruise for AFR's.

wilham320

iTrader: (1)

17??? your crazy...it starts popping and surging once it get up into the 16's. I had it tuned to stoich at cruise, ran for over a year at that, then one day lean?

wilham320

iTrader: (1)

ttt... just got back from iraq wooo whooo!
still broke
anyone got ideas

edit- i thinking it may be tps wire in between emanage and ecu? is if not a good connection there might be a slight voltage drop and it "thinks" the throttle body is closed and goes to decel mode. the tps checks good on the laptop, but if the ecu might not be getting the same signal?


Modified by wilham320 at 10:17 AM 2/23/2007

blackrag

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wilham320 &raquo;</TD></TR><TR><TD CLASS="quote">ttt... just got back from iraq wooo whooo!
still broke
anyone got ideas</TD></TR></TABLE>

give this guy some help. lol. geez..

MassScene

is the drivability different? because it may be a false reading from a new exhaust leak before the wide band..

wilham320

iTrader: (1)

yes driveabily blows, surges, boggs, then i gotta give it throttle for it to richen back up

Bakeoff

you're talking out of your *** if you think 15 or 16 is too lean for cruising. Any more lean than that and I would worry, but that sounds normal. Now, the driveability, you need to get the thing on a dyno and do some datalogging to see what's going on.
What O2 are you running? I'm assuming a wideband, but which one?

wilham320

iTrader: (1)

it has always been stoich at cruise... over a year. 15 i would say is acceptable. 16 is pushing it for a turbo car... stupid high egt's at cruise. thats my opinion... doesn't matter cause it was at 14's, now its not. so there is something wrong.

the car is running stoich at anything past 1/4 throttle, 11's at wot, but at very slight throttle is suddenly goes to 17-19 afr's and sometimes says "lean" on the plx. when it does that it stutters, bogs whatever, i gotta give it more throttle then it pops back to 14's again. dyno won't help, you can only log so much **** on emanage and using plx300. i can do that on the street. the emanage shows tps is good. 0-100% when i test it.

MassScene

so what happens when you try and put more fuel in?