1979lee Posted September 29, 2019 Report Share Posted September 29, 2019 hey guy, well got a problem with my 1997 chevy lumina 3100 v6 118k miles the gas tank is doing a "thumping sound" like thump,thump,thump... and the service engine light is on. code P0440. no gas leaks or smells, car runs just fine, no noticable loss in mpg's. hell if i didnt live in a smog nazi state like ca....... i'd clear the code,say F it...but!!!! its NEVER failed to pass smog test. https://www.fixdapp.com/blog/p0440 i took a look under hood, no smells of gas all connections look good. this car has made this sound before, but never set a code its done it (the sound) before.(turn the key to start the car,fuel pump primes and i'd hear some sound other than the pump). oh yeah, new gas cap, actually i tried 3 different caps, 1,locking 2,one i had on the car 3 my spare cap....so i not think itsthe cap. thanks fellas, ya'll been a big help since i joined in 2006! Quote Link to comment Share on other sites More sharing options...
Schurkey Posted September 29, 2019 Report Share Posted September 29, 2019 First Guess: Tank vent is messed-up. Best bet is to get a REAL service manual and then follow the diagnostic procedure for that code. Quote Link to comment Share on other sites More sharing options...
1979lee Posted September 30, 2019 Author Report Share Posted September 30, 2019 tank vent was my thought too. damn i dont want to pull the tank! i have the service manuals. but cant locate the evap system part Quote Link to comment Share on other sites More sharing options...
walterdude Posted September 30, 2019 Report Share Posted September 30, 2019 My 99 Limina threw that code for YEARS... (I never had any thumping)... I could never track track that one down... I tried a smoke machine and even tried chucking new parts (I think Purge Solenoid,,, new lines,, etc) at it and NEVER could find a definite problem... I found something on a forum about GM using Buggy software... The only way around it was reflashing the PCM... They also talked about a way to reset the Purge Solenoid... That would clear the code BUT,,, it would eventually always come back... I haven't owned or even worked on a W=Body in MANY years and can't really remember much about it... I remember whenever it was due for an emissions test I'd reset the Solenoid if that code was present and I'd be good untill The code showed up again... It wasn't a constant thing... Maybe every year or two... Sorry I can't be of more help,,, as I said it was many years ago... I DO remember it being annoying as HELL... I spent many years as a mechanic and I get irritated the few times I can't find something concrete that's amiss... I'd say Google the hell out of it and read everything you find... I really hope you do better than I did... I couldn't afford to go to the Dealer for a reflash that MIGHT fix it... I just ended up living with it and resetting it when the code did show up... Again sorry I can't remember too much about this,,, Good luck, Tom B... Quote Link to comment Share on other sites More sharing options...
1979lee Posted September 30, 2019 Author Report Share Posted September 30, 2019 11 minutes ago, walterdude said: My 99 Limina threw that code for YEARS... (I never had any thumping)... I could never track track that one down... I tried a smoke machine and even tried chucking new parts (I think Purge Solenoid,,, new lines,, etc) at it and NEVER could find a definite problem... They also talked about a way to reset the Purge Solenoid... That would clear the code BUT,,, it would eventually always come back.. I remember whenever it was due for an emissions test I'd reset the Solenoid if that code was present and I'd be good untill The code showed up again... It wasn't a constant thing... Good luck, Tom B... thanks for the info, i may do just that! ive got till march 2021 to fix this(here in the soviet republic of california,smog is every 2 yrs ) its the code stayed away for a week, i put 70 miles on the car saturday. no issues. today i'm in it for 20 minutes and P0440 GRRR. yes damned annoying. ! Quote Link to comment Share on other sites More sharing options...
walterdude Posted September 30, 2019 Report Share Posted September 30, 2019 (edited) I happened to remember that I "thought" that I "might" have saved a note from a post I had msde on 60deg V6.com Maybe 20 years ago... AND after all those years and PCs that there is one folder on rhis PC that I always put on a new/different machine... Here is a copy... I didn't test if the link is still active,,, it WAS a LONG time ago... Speaking of Dead Links I see 60DegreeV6.com is officially DEAD... That SUCKS... Besides this site 60deg was the ONLY form of social media I ever engaged in... Well,,, hope this helps... Good luck!!! Tom B... Before when this first posted they pulled on of their FAMOUS Fire Drills... I just hit submit and hit the road... I see now that the codes are not exactly the same... I didn't have any thumping going on BUT everything else sounds familiar Running the reset won''t hurt anything AND it just might do some good... I'm back!!!! Just found this link and Explains the PCM Reflash... I'd say the 2 codes in question are VERY closely related... https://forums.edmunds.com/discussion/5667/pontiac/grand-am/pontiac-grand-am-dtc-code-p1404 Fix P1404.txt Edited October 2, 2019 by walterdude Quote Link to comment Share on other sites More sharing options...
1979lee Posted October 8, 2019 Author Report Share Posted October 8, 2019 On 9/30/2019 at 12:44 PM, walterdude said: I happened to remember that I "thought" that I "might" have saved a note from a post I had msde on 60deg V6.com Maybe 20 years ago... AND after all those years and PCs that there is one folder on rhis PC that I always put on a new/different machine... Here is a copy... I didn't test if the link is still active,,, it WAS a LONG time ago... Speaking of Dead Links I see 60DegreeV6.com is officially DEAD... That SUCKS... Besides this site 60deg was the ONLY form of social media I ever engaged in... Well,,, hope this helps... Good luck!!! Tom B... Before when this first posted they pulled on of their FAMOUS Fire Drills... I just hit submit and hit the road... I see now that the codes are not exactly the same... I didn't have any thumping going on BUT everything else sounds familiar Running the reset won''t hurt anything AND it just might do some good... I'm back!!!! Just found this link and Explains the PCM Reflash... I'd say the 2 codes in question are VERY closely related... https://forums.edmunds.com/discussion/5667/pontiac/grand-am/pontiac-grand-am-dtc-code-p1404 Fix P1404.txt 363 B · 3 downloads thank you,tom/all. ill try this! update.10/7/19 (ill try tom's fix next p0440) well if i unplug the canister purge valve the popping/thumping stops.... but then i get a p1655 lol! anyhow. i did get the -canister-vent-valve-solenoid off(it was dusty!), it it bench tested good (so did the -canister-PURGE-valve) so it may be a wireing problem. note to 95-01 lumina owners the evap can, can be accesed via the fuel door, remove 3 7mm screws & plastic around the gas fill, its all there! i got a few scrapes but it beats tire & inner fender removal!!!!!! keeep yall updated Quote Link to comment Share on other sites More sharing options...
ron350 Posted October 9, 2019 Report Share Posted October 9, 2019 (edited) My car is a 96 Regal so this might not apply to your 97 Lumina. My 96 set a code once when the Purge Valve Solenoid got clogged from charcoal or rotten rubber EVAP lines. Removed it from the car applied 12 volts to the pins and blew out the black crud with caned air. Few years later it set the EVAP code again and every thing checked good and I gave up for a while. Had the car up on jack stands to change the fuel filter and found a split EVAP rubber line just in front of the gas tank. This is where the steel EVAP line changes to a rubber line and goes up and over the gas tank to the charcoal canister. From the factory the rubber EVAP line is just pushed on to the steel line with no clamp of any kind. When I pulled the split hose off the steel line was rusted so I had to sand and paint that before cutting off the split rubber and sliding it back on. I then installed a small screw clamp for ½ inch rubber hose to keep the water out and causing more rust. After this there were no more EVAP codes. Later on when I replaced the fuel pump I upgraded all of the EVAP lines with rubber fuel line. After 15 years the EVAP rubber lines were falling apart. Edited October 9, 2019 by ron350 Quote Link to comment Share on other sites More sharing options...
1979lee Posted November 30, 2019 Author Report Share Posted November 30, 2019 hi y'all. well fixed the leak! quick connect going to the tank from the charcole canister was loose. no more damn codes! BUT! its popping WORSE!!!! agggrrrrrrggg WATCH THE VIDEO! DAMMIT! 20191127_130158.mp4 Quote Link to comment Share on other sites More sharing options...
1979lee Posted November 30, 2019 Author Report Share Posted November 30, 2019 (edited) i replaced the parts circled . with nos delco parts. Edited November 30, 2019 by 1979lee Quote Link to comment Share on other sites More sharing options...
chevy99 Posted October 10, 2023 Report Share Posted October 10, 2023 Where is the purge valve located having same issue with that code figured I would start there? Quote Link to comment Share on other sites More sharing options...
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