troubleshooting CEL P0171

[scarface]

I dont have any vacuum leaks, and my MAF sensor is clean.

I did notice however a pretty good exhaust leak on the passenger side manifold/xpipe joint.... you think that could cause this code? Maybe the o2 sensor isnt reading correctly because of it? I noticed the leak after the clutch install, and thats when the code came on too.

any thought?

 

[blackfang]

An exhaust leak will cause a lean condition being there is more air added now. I would fix that leak first, then reset the ecu and see if it changes.

 

[97blackgt]

This Pinpoint Test is intended to diagnose the following:

Heated Oxygen sensor (HO2S) /Heater
HO2S Connections
Vacuum Systems
Fuel Injector(s)
Harness Circuits: HO2S GND, HO2S, INJ 1-8, VPWR and SIG RTN
Powertrain Control Module (PCM)

check intake/ PCV valve
MAF valve

 

[blackfang]

I say fix the leak in the exhaust first and see what that does before trying to find other concerns. Go with the obvious first.

 

[scarface]

thanks guys...Ive checked everything on that list. Its all in working order.

I have bought the gasket, should be here tomorrow. Im confident it is that though. It started right after I removed the xpipe to fix my clutch. no leak before, no CEL before.

now leak, and CEL.

I will report back.

 

[97blackgt]

hopwfully it fixes it man...let us know

 

[scarface]

thanks I will

 

[97blackgt]

any ideas yet scarface...funny thing is i now have a check engine light also, wich i think is due to an exhaust leak on the passenger side manifold. When i trying to take the x pipe off i stripped the nut, and now only one nut is holding the manifold and the x pipe together. I think it is the leak which is causing the problem, just wondering if u fixed yours yet?

 

[scarface]

I havent fixed it yet...I did get the gasket, but Im sure it is the problem...it all happened too close to be coincidence.

 

[97blackgt]

how much did the gasket cost you and where did u get it...i might also have to invest in one.

 

[scarface]

14 shipped from Randy at modular depo...got it in 1 day!

 

[97blackgt]

do you think the ford dealership would have them in stock? and a ballpark for the price?

 

[scarface]

yeah, but Randy is a ford dealership, and he sells at cost. probably around 14 bux or so.

 

[97blackgt]

ohhh i got ya...should be fixing mine tomorrow as long as i can get my car to the auto building...supposed to get 8-12 inches of snow

 

[scarface]

yeah it sucks...we have gotten 3 inches of rain today!

 

[scarface]

the gasket fixed my problem

 

[97blackgt]

fixed mine also....i forgot to post though

now i have another CEL for an 02 sensor :-\ :nonono:

 

[blackfang]

the gasket fixed my problem

Glad to hear it