Code Question

[shatter65]

I have a 97 gtp and its check engine light is on. I went to Autozone and they said the code that was causing the light to come on was PO441 Emissions Purge Flow System Fault. I am clueless to what the problem could be but i need to get this fixed ASAP because i just got a ticket for inspired inspection a few days ago. Thanks for any suggestions

[maxwedge]

Purge flow valve could be stuck open or closed, sits on the vapor cannister, further diagnosis is required to find this problem accurately.

[shatter65]

ok, can you tell me further where that is? or could my chiltons tell me that?

[BNaylor]

Check all of your vacuum lines in the evaporative emissions system. At rear of car by the fuel tank on driver's side there is a charcoal cannister with the vent solenoid. Check there and where they go to the fuel tank. Then where the lines run back to the engine.

On the engine side check vacuum connections from the throttle body to the purge solenoid. Also, check electrical connections at the vent solenoid and purge solenoid for corrosion and tightness.

[shatter65]

i went today to get my car inspected because i turned my check engine light off and i was seeing if i could sneak by, but it still failed.. they said my car was fine except it was running too lean.. they said to check my o2 sensor and maybe that was it.. what do yall think about that?

[maxwedge]

You failed with no cel on and no pending codes? what state is this. Also when you clear the codes it takes a specific drive cycle to reset the emissions monitors, in NYS you would fail if you had just cleared the codes and came in for an obd11 emissions test.

[shatter65]

i live in texas and i did have a pending code still, but i reset my computer so it didnt show up. after a while of them driving it around and messing with it, when they plugged it up, they said it finally threw the code again and it was running to lean..
a few months ago my CAT was clogged so i undid my 02 sensor under the hood to let out some pressure. my cylinder 6 wire was back there and the exhaust basically melted the 6wire. do you think that it could have damaged the o2 sensor too and i just need to replace it to make it not run too lean?

[BNaylor]

Originally Posted by shatter65

i live in texas and i did have a pending code still, but i reset my computer so it didnt show up. after a while of them driving it around and messing with it, when they plugged it up, they said it finally threw the code again and it was running to lean..
a few months ago my CAT was clogged so i undid my 02 sensor under the hood to let out some pressure. my cylinder 6 wire was back there and the exhaust basically melted the 6wire. do you think that it could have damaged the o2 sensor too and i just need to replace it to make it not run too lean?

What DTC error code is showing now? Does it indicate an 02 sensor failure? If the code was pending that is why it failed after the IM status had a chance to complete. Did you ever get the CAT replaced? 02 sensors (fore and aft) can cause the lean trim condition to include a defective EGR valve.

[shatter65]

i went to autozone and the code reader said PO441 Purge Flow system fault
i went to get it inspected and they said it was running too lean
yes i got the cat replaced a few months back
so you say that maybe i should replace the o2 sensor (before the cat under the hood)???

[maxwedge]

P0441 is not related to running lean, how did they determine that, no code was present for it, so it should not be an issue in the inspection.

[shatter65]

i wish i could tell you.. i was thinking the same thing though, that the evap system has nothing to do with running lean..
this is so frustrating..
i dont know what to do..... i guess im just going to have to pay full price for this ticket and pay to get another inspection done some other time because i dont see this problem getting fixed in the next 3 days unless one of yall are a genius and can figure this out..

[BNaylor]

Originally Posted by shatter65

i wish i could tell you.. i was thinking the same thing though, that the evap system has nothing to do with running lean..
this is so frustrating..
i dont know what to do..... i guess im just going to have to pay full price for this ticket and pay to get another inspection done some other time because i dont see this problem getting fixed in the next 3 days unless one of yall are a genius and can figure this out..

Resolve the evaporative emissions DTC error code and you may fix your problem. Certain DTC error codes once set may cause the PCM to command lean trim to the fuel injection system.

[shatter65]

Ok, well i was rereading the inspection papers and it says that it actually threw a different code this time.. it is P0171 System too Lean (Bank 1)
so maybe it is my O2 sensor?

i dont know what all this means but it also says on the monitors:
Misfire: Ready
Fuel Sys: Ready
Comp Cmpt: ready
Catalyst: Not Ready
Heated Cat N/S
Evap: N/S
2ndSys: N/S
Air Cond: N/S
O2 sens: Not Ready
02 Sens Htr: Not Ready
EGR Sys: Not Ready
DLC: PASS

Fault Codes P0171 System too lean (Bank 1)

maybe all the not readys have something to do with me reseting my computer right before i took it to get inspected. What does the N/S, Ready, and Not ready mean?

im about to go back up to autozone to see what codes are being thrown again.

[BNaylor]

Originally Posted by shatter65

Ok, well i was rereading the inspection papers and it says that it actually threw a different code this time.. it is P0171 System too Lean (Bank 1)
so maybe it is my O2 sensor?

i dont know what all this means but it also says on the monitors:
Misfire: Ready
Fuel Sys: Ready
Comp Cmpt: ready
Catalyst: Not Ready
Heated Cat N/S
Evap: N/S
2ndSys: N/S
Air Cond: N/S
O2 sens: Not Ready
02 Sens Htr: Not Ready
EGR Sys: Not Ready
DLC: PASS

Fault Codes P0171 System too lean (Bank 1)

maybe all the not readys have something to do with me reseting my computer right before i took it to get inspected. What does the N/S, Ready, and Not ready mean?

im about to go back up to autozone to see what codes are being thrown again.

It is possible its the 02 sensor but other things can cause the P0171 error code but the 02 sensor is on the list. Ideal fuel trim = zero. Greater than zero indicates the PCM is adding fuel to compensate for the lean condition. If fuel trim is less than zero the PCM is reducing the amount of fuel to compensate for a rich condition.

Here is the course of action per the GP GM service manual:

Check all vacuum hoses at intake system.
PCV Valve
Possible throttle body blockage (clean input screen and body)
IAC (idle air controller valve)
Check fuel injectors (bad o-ring seal)
MAF sensor
EGR valve
Check 02 sensor

[maxwedge]

The other monitors are not ready because after clearing the codes there is a drive cycle required to set the emissions monitors, which can also cause an emissions test failure because it cannot check certain required components.