Problem Identified? (P0172)

[Matthew]

right john but im getting "too rich" not "too lean"

corwin, according to keith, the clamp will pass a certain voltage above like .35 to the ECU if the voltage is higher. the if the voltage is lower it lets that pass as well and lets the ECU "help" add fuel.

 

[TheJohnny]

maybe the exhaust is leaking out and the fumes are staying resident in the pipe leaving you with an overly rich condition... hey, this is outside of anything I would know so I wish you the best of luck on it. I wish I could help man Good luck.

 

[Mr. Win]

yes matthew thats how the voltage clamp works.

 

[LinuxRacr]

Damn Matthew, looks like you are going thru some of the same problems I went thru. The clamp tuned out not to be the issue. I had two of them.

 

[Matthew]

so....

 

[LinuxRacr]

I'm all out of advice for now. If you have already tried what I suggested, and it didn't work, not sure what to tell you at this point.

 

[Matthew]

i have to ask again for a better pic of that line..

 

[LinuxRacr]

i have to ask again for a better pic of that line..

Take a look under the hood, and look where the line goes from the purge solenoid. There are two lines, so two possible connections. One goes to the catch can, and one goes to the nipple on the throttle body.

 

[Matthew]

alright ill double check tommorrow.

 

[Captain KRM P5]

running that high of a fuel pressure you may have worn out your fuel pump - just a thought. i wore out mine and it drove fine until i went into boost, then it leaned out regardless of how high i set the fuel pressure.

 

[Matthew]

no its still good

 

[Captain KRM P5]

no its still good

no offense, how can you tell?

 

[Matthew]

cause the fuel press guage is still reading 100psi on the with a walbro pump

 

[changedman]

get the haltech and sell your pump and etc.

 

[Matthew]

give me the money

 

[Aricjm15]

100psi does seem like alot
the only time the ECU will pull fuel is at partial throttle,the clamp only works at partial throttle. I think someone already said that though, but once you floor it your car should be running rich as hell.
are you lean under full or partial throttle?

 

[Matthew]

both. im thinking because of the CEL the ECU is pulling fuel at all times.

 

[Captain KRM P5]

cause the fuel press guage is still reading 100psi on the with a walbro pump

at full boost it reads 100 psi? as aric said, at WOT the car should not be pulling fuel but at partial throttle it would. thus the need for the voltage clamp. perhaps the ECU threw a "too rich" CEL because you initially ran it too rich and now it is trying to counter that condition by pulling fuel and all you do is add more fuel to countercounter check the clamp wiring and reset the ecu. maybe a shaky theory

 

[Matthew]

ive done that a hundred times and it keeps coming back. it reads 100psi at full boost. but how is it seeing a rich condition i have no idea, because as i said to corwin i didnt boost but one time early in the week (read: the fuel pressure stayed way down all week, and AFRs stayed way up) and then got the rich cel late in the week.

i will turn down the pressure to accomodate, reset, and see if it comes back, but im about 99 percent sure it will.

and once again, why do this to me now, and never before with my old kit? not that the kit is at fault, im just using it as a frame of time reference.

 

[Matthew]

any ideas what idle setting should give me ample fuel pressure at 6.5psi of boost?