the codes:

P0170
P0171

both of which deal with running lean, and i've seen them before, but every now and then, they keep popping back up, this time after a spirited night of driving (and beating up on an STi).

i believe one of them specifically states running lean in bank 1. what's bank 1?

possible problems ... someone stop me if i'm on the wrong track:
-ESM may have a short cuz i believe this was the same code i saw when i was having ESM issues.

-spark plugs need to be checked. i've been running IK24's since the SC install, and i might wanna pull them to see what they look like. i think i have about 6k miles on them now. they're currently gapped to .035".

anything else anyone can think of to ensure that all is well in s2k land?

 

You typed "P0179". Are you sure you didn't mean "P0107"? This would be MAP sensor. Hence, I would suspect that your ESM connections need to be looked at. Maybe some of them have come loose or corroded. If this happened, then it could lead to the wrong fuel metering (lean). Perhaps a re-solder?

 

nope. it was definitely 0170 and 0171 and not 0179 or 0107.

 

P0170
Fuel Trim Malfunction (Bank 1)
P0171
System too Lean (Bank 1)
I believe this occurs when the ECU tries to set its correction factor to enable the desired AFR tobe reach.... Not sure if Im making sence here but bacially when the ecu sees a too lean/rich condition it makes changes via a feedback loop.... now when it has met a certain threshold it will trigger the CEL... I would reset the ecu and see if it happens again....
BTW are you using a WIDE BAND TO MONITOR YOUR AFR..........
I THINK IT WOULD BE A VERY GOOD IDEA IF OTHERWISE.....

 

i had that code once and it's gone. something system to0 lean bank1 crap right?

you have a s/c'er dont you???

Awhile back i noticed (1) a broken straw like leaking air sound coming from the fuel pump. (2) the fuel pump would be really loud (whining) after long drives.

The stock pinch type clamps that hold the hoses on the fuel pump don't seal as good. you should replace those w/ the bolt type band clamps like the vortech kit uses. this probably cause the fuel pump to run a lil too hard than it should or not sucking the fuel right. You could buy them at autozone for 1.00

moreover, you should NEVER drive your car hard when you see the gas light pop up, especially if your vtec'ing too. I'm not saying you did, but my car didn't like it!never again. It bogged and it was probably good enough to throw a cel overtime, but it didn't at that momemnt. I'm guessing the fuel pump w/ the crappy stock clamps on an almost empty tank of gas probably didn't have enough gas suction compensate the extra air the s/c'er puts in??? my hypothesis...

I have my denzo ik24's gapped to .030 and i even did a valve adjusment on top of that. engine feel smooth as butter

I noticed my engine used to sputter if i blimp the thottle and let it idle - it would drop past 1k then sputter then it'd be fine. Map whack did the trick, but i replaced it. i even clean the t.b. (carb cleaner) while i was at it.

uhm. what else... oh yah, definatly check the connections on the esm. i have t-taps, so i took some wrench plyers and gave them a lil pinched to ensure a better connnection.

lastly, ECU reset. Hopefully that cel will never come up again

all these suggestion might not be related, but its what i did to get rid of that cel.

good luck
PJ

 

I have gotten a cel before but I never pulled the code since it went away after i reset the ecu. It always seemed that the code would occur after a hard acceleration and I let off the gas and let it coast - I see the wideband displaying "Lean" so I'm assuming I am probably getting the same code.

Do you let off the gas completely after a hard acceleration? Or do you gradually let off the gas?

It does make sense since you are using a lot of fuel and when you let off the gas and put it in neutral - that's no boost so the fmu wouldn't be supplying extra fuelthat would be needed - so you would enter a lean condition for a split second - long enough to trigger a cel. With the cel on - my car drives normal - I don't feel any difference in performance - although I never vtec if the cel is on.

I am using the emanage and I increased the fuel slightly in the lower rpms and I have not gotten the cel again.

Just a thought.

 

your scenerio could make sense, and i was playing with a STi and did just after he let up on the gas, but it was a good 5 mins later when the cel came on .. or maybe i just didn't notice it til then. hard to tell.

 

Whenever you let off the gas (deceleration), the injectors are cycled off, so you would run lean.