Dtc 404, 1441??
Blk&BluGTP
02-15-2005, 12:15 AM
my check engine light has beeen on for a while so i finally got to autozone and they told me i have a 404 EGR something code and a 1441 code also, now obviously codes only point you in the right direction and not to the specific component. now i have neither the time or the money to diagnose htis my self or bring it to a shop at the moment so if anyone has had these before and may be of help as to what it is exactly it would be great
Blk&BluGTP
02-15-2005, 12:15 AM
ohh yea the car is a 2000 gtp
BNaylor
02-15-2005, 12:35 AM
my check engine light has beeen on for a while so i finally got to autozone and they told me i have a 404 EGR something code and a 1441 code also, now obviously codes only point you in the right direction and not to the specific component. now i have neither the time or the money to diagnose htis my self or bring it to a shop at the moment so if anyone has had these before and may be of help as to what it is exactly it would be great
ODB-II DTC Codes:
PX404 is: EGR Flow CKT Range/Perf
PX441 is: EVAP Emission Control System Purge Flow Fault
What's the mileage on the car? There are other posts in this forum similar in nature which may be helpful to you on resolving the issues.
Good luck!
ODB-II DTC Codes:
PX404 is: EGR Flow CKT Range/Perf
PX441 is: EVAP Emission Control System Purge Flow Fault
What's the mileage on the car? There are other posts in this forum similar in nature which may be helpful to you on resolving the issues.
Good luck!
Blk&BluGTP
02-15-2005, 12:49 PM
the car has 87k and has been modded the basics.. catback intake 3.4 pulley etc if you are aware of other posts that may help please link them in a reply
BIG-L
02-15-2005, 01:40 PM
PO404 Sounds as if the EGR valve maybe sticking or stuck.
Try tapping on and around it with the handle end of a screwdriver, it's not uncommon for a piece of carbon to get stuck in there.If that fails it maybe time to try and clean it or if that dosent work,replace the EGR valve.If you take if off you will need a new gasket,because the old one will be stuck on there from the heat.There is a company called Tomco that makes a gasket that has a screen in it to keep that from happening it's called GM Klean Screen Gasket Part # 2-1357.
The EGR valve is located next to the firewall,by the end of the crossover
Here is a picture of the location,but with a block off plate.
http://www.zzperformance.com/products_img/229_1.jpg
http://www.smpcorp.com/web_app/catalog/images/EGV466.jpg
P1441 Diagnostic Chart
Emission Hose Routing Diagram is located under the hood
SYSTEM DESCRIPTION
The Powertrain control Module (PCM) supplies a ground to energize the EVAP purge valve (purge on). The EVAP purge valve control is Pulse Width Modulated (PWM) or turned on and off several times a second. The duty cycle (pulse width) is determined by engine operating conditions including load, throttle position, coolant temperature and ambient temperature. The duty cycle is calculated by the PCM and the output is commanded when the appropriate conditions have been met. The system checks for conditions that cause the EVAP system to purge continuously by commanding the EVAP vent valve ON (Closed) and the EVAP canister purge valve OFF (Closed). If vacuum level in the fuel tank increases during the test, a continuous purge flow condition is indicated. This can be caused by any of the following conditions:
The following conditions will set a DTC P1441.
EVAP canister purge valve leaking internally.
EVAP purge and engine vacuum lines switched at the EVAP canister purge valve.
EVAP canister purge valve control circuit grounded.
CONDITIONS FOR RUNNING THE DTC
All conditions for DTC P0440, P0442 and P0446 diagnostic tests have been met and passed.
CONDITIONS FOR SETTING THE DTC
A continuous open purge flow condition is detected during the diagnostic test (fuel tank pressure decreases to less than -11 in. H2O.
ACTION TAKEN WHEN THE DTC SETS
The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.
The PCM will store conditions which were present when the DTC set as Freeze Frame and Failure Records data.
If the misfire is determined to be catalyst damaging, the PCM will flash the MIL.
CONDITIONS FOR CLEARING THE MIL/DTC
The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
The history DTC will clear when the PCM turns OFF the MIL.
The DTC can be cleared by using a scan tool.
DIAGNOSTIC AIDS
Check for the following conditions:
Incorrect vacuum line routing. Verify that the source vacuum line routing to the EVAP purge valve is correct and that the EVAP purge and source vacuum lines to the EVAP canister purge valve are not switched.
Malfunctioning or damaged canister.
Inspect for carbon releasing the EVAP system. Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to set occurs. This may assist in diagnosing the condition.
If the harness appears to be OK, connect the J41413 EVAP Pressure/Purge Diagnostic Station to the EVAP service port, pressurize the EVAP system to 10 in. H2O and observe the Fuel Tank Pressure parameter on the scan tool while moving connectors and wiring harnesses related to the EVAP purge valve. A sudden change in the display will indicate the location of the malfunction.
IMPORTANT: Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.
Poor terminal connection. Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Use a corresponding mating terminal to test for proper tension. Refer to Diagrams for diagnosis and repair.
Damaged harness. Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Diagrams for diagnosis and repair.
Inspect the PCM and the engine grounds for clean and secure connections.
If the DTC is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set.
TEST DESCRIPTION
Numbers below refer to the step numbers on the Diagnostic Table:
The Powertrain On Board Diagnostic (OBD) System Check prompts you to complete some of the basic check and store the Freeze Frame and Failure Records data on the scan tool if applicable.
Try tapping on and around it with the handle end of a screwdriver, it's not uncommon for a piece of carbon to get stuck in there.If that fails it maybe time to try and clean it or if that dosent work,replace the EGR valve.If you take if off you will need a new gasket,because the old one will be stuck on there from the heat.There is a company called Tomco that makes a gasket that has a screen in it to keep that from happening it's called GM Klean Screen Gasket Part # 2-1357.
The EGR valve is located next to the firewall,by the end of the crossover
Here is a picture of the location,but with a block off plate.
http://www.zzperformance.com/products_img/229_1.jpg
http://www.smpcorp.com/web_app/catalog/images/EGV466.jpg
P1441 Diagnostic Chart
Emission Hose Routing Diagram is located under the hood
SYSTEM DESCRIPTION
The Powertrain control Module (PCM) supplies a ground to energize the EVAP purge valve (purge on). The EVAP purge valve control is Pulse Width Modulated (PWM) or turned on and off several times a second. The duty cycle (pulse width) is determined by engine operating conditions including load, throttle position, coolant temperature and ambient temperature. The duty cycle is calculated by the PCM and the output is commanded when the appropriate conditions have been met. The system checks for conditions that cause the EVAP system to purge continuously by commanding the EVAP vent valve ON (Closed) and the EVAP canister purge valve OFF (Closed). If vacuum level in the fuel tank increases during the test, a continuous purge flow condition is indicated. This can be caused by any of the following conditions:
The following conditions will set a DTC P1441.
EVAP canister purge valve leaking internally.
EVAP purge and engine vacuum lines switched at the EVAP canister purge valve.
EVAP canister purge valve control circuit grounded.
CONDITIONS FOR RUNNING THE DTC
All conditions for DTC P0440, P0442 and P0446 diagnostic tests have been met and passed.
CONDITIONS FOR SETTING THE DTC
A continuous open purge flow condition is detected during the diagnostic test (fuel tank pressure decreases to less than -11 in. H2O.
ACTION TAKEN WHEN THE DTC SETS
The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.
The PCM will store conditions which were present when the DTC set as Freeze Frame and Failure Records data.
If the misfire is determined to be catalyst damaging, the PCM will flash the MIL.
CONDITIONS FOR CLEARING THE MIL/DTC
The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
The history DTC will clear when the PCM turns OFF the MIL.
The DTC can be cleared by using a scan tool.
DIAGNOSTIC AIDS
Check for the following conditions:
Incorrect vacuum line routing. Verify that the source vacuum line routing to the EVAP purge valve is correct and that the EVAP purge and source vacuum lines to the EVAP canister purge valve are not switched.
Malfunctioning or damaged canister.
Inspect for carbon releasing the EVAP system. Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to set occurs. This may assist in diagnosing the condition.
If the harness appears to be OK, connect the J41413 EVAP Pressure/Purge Diagnostic Station to the EVAP service port, pressurize the EVAP system to 10 in. H2O and observe the Fuel Tank Pressure parameter on the scan tool while moving connectors and wiring harnesses related to the EVAP purge valve. A sudden change in the display will indicate the location of the malfunction.
IMPORTANT: Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.
Poor terminal connection. Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Use a corresponding mating terminal to test for proper tension. Refer to Diagrams for diagnosis and repair.
Damaged harness. Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Diagrams for diagnosis and repair.
Inspect the PCM and the engine grounds for clean and secure connections.
If the DTC is determined to be intermittent, reviewing the Failure Records can be useful in determining when the DTC was last set.
TEST DESCRIPTION
Numbers below refer to the step numbers on the Diagnostic Table:
The Powertrain On Board Diagnostic (OBD) System Check prompts you to complete some of the basic check and store the Freeze Frame and Failure Records data on the scan tool if applicable.
Blk&BluGTP
02-16-2005, 12:31 AM
well thanks for the ideas, hopefully sometime this weekend i will have time to check it out weather permitting of course i dont have a scan tool but i am plenty capable of hitting things wiht a screwdriver :biggrin: and as for the other code i have had problems with my evap system before but it was setting a different code and it all boiled down to a blown fuse under the hood, which isnt blown this time
Blk&BluGTP
02-20-2005, 09:21 PM
i was going through the diagnostic flow for the egr valve took voltage readings on harness and everything checked out so i got to the continuity check of the actual valve across the certain pins
"use an ohmmeter to check the continuity of the EGR valve position sensor and egr solenoid coil. check across terminals 2 and 4 and terminals 1 and 5 if either check reveals an open circuit replace the egr valve... so my limited knowledge needs this information......
how do i know an open circuit off of an ohm reading.. to me a continuous circuit would have some kind of resistance and when i probe the terminals all i get is no indicated readout so is this an indication of an open circuit???????? if not what is an open circuit indication...
also L, that information you posted on here for me to look at for other code where did you get that from. i found a website at one point that gave diagnostic info for each gm car chevy pontiac etc, based upon all the different trouble codes.. and the information sounded alot like what you posted only problem is i cant remember the site i had so i was wondering if where you got that info was same place i used at one point.
thanks for any continuing help
"use an ohmmeter to check the continuity of the EGR valve position sensor and egr solenoid coil. check across terminals 2 and 4 and terminals 1 and 5 if either check reveals an open circuit replace the egr valve... so my limited knowledge needs this information......
how do i know an open circuit off of an ohm reading.. to me a continuous circuit would have some kind of resistance and when i probe the terminals all i get is no indicated readout so is this an indication of an open circuit???????? if not what is an open circuit indication...
also L, that information you posted on here for me to look at for other code where did you get that from. i found a website at one point that gave diagnostic info for each gm car chevy pontiac etc, based upon all the different trouble codes.. and the information sounded alot like what you posted only problem is i cant remember the site i had so i was wondering if where you got that info was same place i used at one point.
thanks for any continuing help
BNaylor
02-20-2005, 10:58 PM
i was going through the diagnostic flow for the egr valve took voltage readings on harness and everything checked out so i got to the continuity check of the actual valve across the certain pins
"use an ohmmeter to check the continuity of the EGR valve position sensor and egr solenoid coil. check across terminals 2 and 4 and terminals 1 and 5 if either check reveals an open circuit replace the egr valve... so my limited knowledge needs this information......
how do i know an open circuit off of an ohm reading.. to me a continuous circuit would have some kind of resistance and when i probe the terminals all i get is no indicated readout so is this an indication of an open circuit???????? if not what is an open circuit indication...
also L, that information you posted on here for me to look at for other code where did you get that from. i found a website at one point that gave diagnostic info for each gm car chevy pontiac etc, based upon all the different trouble codes.. and the information sounded alot like what you posted only problem is i cant remember the site i had so i was wondering if where you got that info was same place i used at one point.
thanks for any continuing help
Reply:
An open circuit means no continuity when you measure between the designated points mentioned by L. For example: On my autoranging digital volt/ohmmeter an open reads 10.00 megohms. When you measure across the two points and get a reading of zero (0.00), this means continuity or short, etc. You may not get exactly a reading of zero ohms because you may pickup the circuit resistance from possibly the coil of the soleniod and any electrical components such as a diode, etc.
An analog voltmeter/ohmmeter is easier to use. In the ohms position whether on X1, X10, x100 and up the meter needle will defect to the far right indicating continuity. An open circuit is shown by the needle staying far left.
"use an ohmmeter to check the continuity of the EGR valve position sensor and egr solenoid coil. check across terminals 2 and 4 and terminals 1 and 5 if either check reveals an open circuit replace the egr valve... so my limited knowledge needs this information......
how do i know an open circuit off of an ohm reading.. to me a continuous circuit would have some kind of resistance and when i probe the terminals all i get is no indicated readout so is this an indication of an open circuit???????? if not what is an open circuit indication...
also L, that information you posted on here for me to look at for other code where did you get that from. i found a website at one point that gave diagnostic info for each gm car chevy pontiac etc, based upon all the different trouble codes.. and the information sounded alot like what you posted only problem is i cant remember the site i had so i was wondering if where you got that info was same place i used at one point.
thanks for any continuing help
Reply:
An open circuit means no continuity when you measure between the designated points mentioned by L. For example: On my autoranging digital volt/ohmmeter an open reads 10.00 megohms. When you measure across the two points and get a reading of zero (0.00), this means continuity or short, etc. You may not get exactly a reading of zero ohms because you may pickup the circuit resistance from possibly the coil of the soleniod and any electrical components such as a diode, etc.
An analog voltmeter/ohmmeter is easier to use. In the ohms position whether on X1, X10, x100 and up the meter needle will defect to the far right indicating continuity. An open circuit is shown by the needle staying far left.
Blk&BluGTP
02-21-2005, 10:28 AM
ok so my ohmmeter/.voltmeter is a digital one and when i put it on ohms it shows a readout of 1 with the probes just in the air and when i probe the 2 and 4 terminals and the 1 and 5 terminals the readout doesnt change at all it stays on 1 no matter what scale im reading so this is an indication of an open circuit and therefore a bad egr valve according to the directions ??
BNaylor
02-21-2005, 11:14 AM
ok so my ohmmeter/.voltmeter is a digital one and when i put it on ohms it shows a readout of 1 with the probes just in the air and when i probe the 2 and 4 terminals and the 1 and 5 terminals the readout doesnt change at all it stays on 1 no matter what scale im reading so this is an indication of an open circuit and therefore a bad egr valve according to the directions ??
I would agree. Based on your specific ohmmeter you have an open, indicating that the EGR solenoid is bad which is consistent with the DTC error code 404 (circuit malfunction). Good luck!
I would agree. Based on your specific ohmmeter you have an open, indicating that the EGR solenoid is bad which is consistent with the DTC error code 404 (circuit malfunction). Good luck!
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