Hello. I have a 2004 Suzuki XL 7. I am havind an issue with code with DTC P0449: Evaporative Emission System Vent Valve/Solenoid Circuit. I replaced the part, cleard the code and the code keeps coming back after I restart the car. I got a smoke test conducted on the emission system, and the only leakage found is around the filter part number 18581-65d00 and where the hose connection is made to the filter. In speaking with the mechanic, he stated that leakage in that area is normall and that should not give the falut code. Can you help me understand if the filter could be the root cause of the code? Is the filter suppose to bleed or is it suppose to maintain a leak proof system? As a reference I am looking at the suzuki 2004 xl7 part's catalog figure 23 page 27.
Along with the smoke test test did they also do a leak flow test to see if there were any excessive amount of leak/volume of leak that could set a code?
January, 5, 2013 AT 4:51 PM
I believe they conducted a very extensive leak test. They kept the car for a couple of days, and told me the only area where leakage was present was where the filter was located. Granted, I was there when the tet was done. If you would like, I can contatct the shop and ask specifics about the test.
In addition, in speaking with the mechainc, he was very baffled as to why the code was coming back. As a guess, he said it could be the purge valve, but then the purge valve would carry their own fault code p0445 if I am not mistaken.
January, 5, 2013 AT 5:20 PM
Jjust to add, the code when cleared is a 2 trip failure before setting a new code.
If it came back on right away, there is an electrical issue with controls. The tech needs to expand his search to controls from the pcm.
January, 5, 2013 AT 5:49 PM
By electrical issues, are you referring to ground fault, loose connection?
I have the shop manual for the 2004 suzuki xl-7. I plan on doing some diagnostics on the PCM and looking for loose wiring.
January, 5, 2013 AT 5:57 PM
Yes to both but more important is the pcm controlling the vent
January, 5, 2013 AT 6:18 PM
Usually there is a constant power to the vent solenoid with the key in the run position. Then the pcm opens and closes the valve with a ground control.
January, 5, 2013 AT 6:20 PM
Could even be a open terminal to the connector to it.
January, 5, 2013 AT 6:22 PM
Could be anyone of a hundred things, thats what a diag is all about
January, 5, 2013 AT 6:24 PM
Understand. I am on my way to do a diagonostic now. I have seen on this forum where a simple test can be conducted to determine the voltage from the PCM. According to this forum and the shop manual (which are basically the same) the C51-2-18 terminal should exhibit a 10 to 14 Volt reading.
The steps are outline below. Keep in mind this is without the use of what the manufacture calls a Suzuki scan tool. I guess they figure not everyone will have that scan tool. I know I don't and I have priced one and they are quite expensive.
So in detail the steps from the manual are as follows.
A) Remove ECM cover and disconnect connectors from ECM with the ignition switch turned off.
B) Check for proper connection to vent valve at C51-2-18 terminal.
C) If OK, measure voltage at C51-2-18 terminal of ECM connector disconnected with ignition switch turned On.
The voltage should between 10-14 V.
Regarding my initial question, should there be leakage around the filter?
By-the-way, I really appreciate all the responses.
Being a mechanical engineer, I have diagnosed and solved some very intricate problems on my car which the dealer could not solve. Put simply, in the past, I showed them how to fix my car.
This problem here has me a little stumped.
January, 5, 2013 AT 6:25 PM
Also measure the resistance across the vent solenoid and post the measurement?