P0446
January 10th, 2016, 10:13 PM
#11
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Having the exact same issues with 2008 Tahoe. Almost a year ago the P0449 code was being thrown and I had problems getting fuel into the tank which ended up being the purge valve. Everything was great for a few months, then the computer started throwing the damned P0446... so far I have changed out the gas cap and the vent solenoid just like you with no luck.
Guess the next cheapest option is to try and replace the ftps... sure wish I knew someone with a big lift to get the truck elevated. Guess I'll buy a couple of those ramps you see at autozone :/
Guess the next cheapest option is to try and replace the ftps... sure wish I knew someone with a big lift to get the truck elevated. Guess I'll buy a couple of those ramps you see at autozone :/
January 11th, 2016, 7:54 AM
#12
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Bought mine used from a guy who kept great records. No records indicate alteration of fuel pump assembly. I have over 170,000 miles on it now though so problems like this are a little expected.
I went and ran my code again last night and it has now changed to P0455... The P0455 large leak code is making me think: A) my aftermarket vent solenoid is not getting enough electrical power to click closed when the computer is running the vacuum test on EVAP; or B) there is an actual leak in my system and I need a smoke test done.
I'm a beginner at all this and have made a point lately to try and learn as much as I can and fix my own problems just to gain general working knowledge, but it looks like I may be needing some assistance this time unless I want to buy a digital multimeter tool to test the wiring to the evap solenoid and/or try changing out the ftps first.
I went and ran my code again last night and it has now changed to P0455... The P0455 large leak code is making me think: A) my aftermarket vent solenoid is not getting enough electrical power to click closed when the computer is running the vacuum test on EVAP; or B) there is an actual leak in my system and I need a smoke test done.
I'm a beginner at all this and have made a point lately to try and learn as much as I can and fix my own problems just to gain general working knowledge, but it looks like I may be needing some assistance this time unless I want to buy a digital multimeter tool to test the wiring to the evap solenoid and/or try changing out the ftps first.
January 11th, 2016, 2:20 PM
#13
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Bought mine used from a guy who kept great records. No records indicate alteration of fuel pump assembly. I have over 170,000 miles on it now though so problems like this are a little expected.
I went and ran my code again last night and it has now changed to P0455... The P0455 large leak code is making me think: A) my aftermarket vent solenoid is not getting enough electrical power to click closed when the computer is running the vacuum test on EVAP; or B) there is an actual leak in my system and I need a smoke test done.
I'm a beginner at all this and have made a point lately to try and learn as much as I can and fix my own problems just to gain general working knowledge, but it looks like I may be needing some assistance this time unless I want to buy a digital multimeter tool to test the wiring to the evap solenoid and/or try changing out the ftps first.
I went and ran my code again last night and it has now changed to P0455... The P0455 large leak code is making me think: A) my aftermarket vent solenoid is not getting enough electrical power to click closed when the computer is running the vacuum test on EVAP; or B) there is an actual leak in my system and I need a smoke test done.
I'm a beginner at all this and have made a point lately to try and learn as much as I can and fix my own problems just to gain general working knowledge, but it looks like I may be needing some assistance this time unless I want to buy a digital multimeter tool to test the wiring to the evap solenoid and/or try changing out the ftps first.
Use OEM parts:
January 11th, 2016, 7:18 PM
#14
I just wish they would have checked the ftp sensor. by doing that, and if it did not change readings...it would be safe to assume the leak check was good/no leak present and the sensor was the problem.
January 11th, 2016, 9:09 PM
#15
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do you drive on dirt roads or dirty/dusty areas a lot? Dirt can wreck the evap vent system in a hurry if you don't relocate the vent, a lot of cases the charcoal canister ingests dirt and needs replaced also. If you're getting a p0446 and don't have a scantool i'd start by unhooking the lline that goes from the vent solenoid to the canister and checking for dust/dirt inside them both
January 14th, 2016, 9:25 PM
#16
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do you drive on dirt roads or dirty/dusty areas a lot? Dirt can wreck the evap vent system in a hurry if you don't relocate the vent, a lot of cases the charcoal canister ingests dirt and needs replaced also. If you're getting a p0446 and don't have a scantool i'd start by unhooking the lline that goes from the vent solenoid to the canister and checking for dust/dirt inside them both
January 30th, 2016, 7:40 PM
#17
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It is the fuel tank pressure sensor that is bad for me. Had another shop diagnose it and it read -14 with the gas cap off and vent solenoid open. I have the part now, just have to wait until the weather matches my free time.
January 31st, 2016, 10:12 AM
#18
thanks for posting the fix!
It is easier if you lower the tank a little...some people remove the rear driveshaft too. blow all the dirt from the top of the tank, disconnect the electrical connector and pop it straight up with a trim tool or small pry bar. hopefully the old green grommet/seal comes off with the sensor. you may need to grab it with a pick if it stays behind.
It is easier if you lower the tank a little...some people remove the rear driveshaft too. blow all the dirt from the top of the tank, disconnect the electrical connector and pop it straight up with a trim tool or small pry bar. hopefully the old green grommet/seal comes off with the sensor. you may need to grab it with a pick if it stays behind.
