[corvairbob]

ok this has been down the road but i can't find anything on this. i got the p0440 and like everyone else i changed the gas cap.still get it. i looked for the evap solenoid under the hood and did not find it. i did follow the vac line from the center port and that goes to the drivers side fender so i have no idea what that is going to yet. one line with a check on it goes down to under the radiator and there is some device under the radiator and i have not figured that out yet, unless it is a air pump it has a larger hose on it. and another lint that looks to be going to the back.

i know the canister is behind the axle and there is a valve there that they say stays on and you have to power it off. i want to do a smoke test and none to the hoses on the tb let me get smoke past the tb. so i stuck the smoke hose in the filler and shoved in a rag and the only place i get smoke is from the filler at the hose. the rag is not able to seal 100%

so where do you tie into the evap to do a smoke test to find any leaks? i did not see anything when the smoker was in the filler around the tank or the evap canister. and when i plugged into the center port on the tb i got smoke out the breather so that port goes into the tb so it must be full vac when running to what ever that is inside the fender.

i do not drive it enough to have it cycle the light off it the cap fixed the issue so maybe it will not return and that may be why i have no smoke anywhere as the cap did fix it. but if not i want to get a head start on the test so i can get ready to smoke test it again.

by the way what is that device under the radiator? and what is in the driver's side fender that is run by vacuum?

thanks for any help on this one.

 

[oldeerslayer]

The evap purge valve is on the pass side of the intake near the coil.It has one 2 wire plug to operate it and a QD plastic hose that disappears behind the head. You could put smoke in to that line. To disconnect it push in on one side of the QD fitting and it'll pull off easily. If it doesn't, push in on the other side of the white tab. It goes back to the canister. The vent valve is a little ways ahead and toward the center of the truck from the canister. It has 1/2" hoses going to it and should be easy to spot.
The thing under the rad support is the secondary air injection pump. The vacuum hose from the engine on the drivers side goes to a tee or 2 for the HVAC and 4wd and into the fender where the vacuum storage reservoir is located. They used to use a ball under the hood, but by placing it between the inner and outer fender there is more room under the hood.
440 is for a large leak so look over all the nearby hoses for cracks or the vent valve may not be closing.

 

[corvairbob]

ok i did try smoking at the filler and all those lines at the tb and could not get anything. so i will look for that valve your telling me to look for and then if i find it and test at that point i may be able to see any leaks. changing the cap did nothing but like i said i may have not driving it far enough yet to get it to test out. but i will still try to smoke it again and see. i did find a bad hose going the that tee and that reservoir in the fender and clipped the ends to get good connections, so i may have a bad line elsewhere being it is older that god.
a few youtubes show some type of evap test port but i did not see that yet either.
thanks

 

[corvairbob]

ok i found the purge valve setting on the frame rail under the heater bos. boy is that hard to get to. i also found the evap test port and i pushed smoke into that and go nowhere. so the purge valve must have been closed and i do not have the tool to force it open. my scanner form hf showed me that the evap has not completed the test after i reset it

however i do smell gas around the filler and when i was under the car looking for the hoses and the canister vent at the vent iarea i couls smell gas. but that may be because i had the smoker going and maybe that put pressure on the vent. but i should have seen smoke. it may be the canister is full and the vent just lets the fumes out. but we do not test here and i drive this about 3 tanks of gas a year and it is 20 year old, so because i can't force the valves to open or close that is as far as i'm going i will just reset the code when it shows up. thanks

 

[oldeerslayer]

If you drive it that little, ignore the darn thing. It doesn't effect driveability. If you can smell gas you do have a leak. It could be a rust hole in the tank.
The vacuum hose you repaired under the hood is not in any way connected to the evap system. That's engine vacuum and a leak there can effect the engines performance.
P0440 will appear if there is any leakage anywhere in the tank, filler hoses, vent hoses, fuel pump assembly or seal, fuel tank pressure sensor or seal, canister, vent valve, and I'm sure I've forgotten a few. If you have annual inspections, then you have a problem. If not forget it.

 

[corvairbob]

thanks i figured that. i either have a stuck open vent valve unless they are open and are told to close. or a canister or a hose on the tank. the tanks i plastic and i do not see any wet spots around the filler or tank.

and like you said because i do not drive it much it is going to just set ther and leak i guess. if i was to take down the tank and canister i would have to replace every bolt as it is a ton of rust now under there. the truck see's more witners than summers as when i worked i rode a bike it ahs close to 200k if not more now so it is on it's last legs. thanks

 

[corvairbob]

ok i think i found the issue. i took off the filler neck and this is what i found. i filled the tank last friday and yesterday i hag gas around the filler neck at the hose. so i took off the filler neck and found it full of holes. so i think that is why i got the code. and the gas smell. see the photo that may be the reason, but after i repair it i may find other code issues, have to take it one item at a time. normally for this old of a car i would not bother but the gas smell in the garage bothered me to the point of safety. do not need the fumes to get so bad i get an explosion. or fire. my corvair is not evac equipped and i do not get that bad of a smell for it so this was just to bad to leave. the overflow vent did not eant to come out of the hose so i had to break it but just to the hose side of that break i had lots of pin holes also. the neck i show just a few but i expect if i was to look closer i would find a lot more. but this is all it takes for the code. thanks

 

[Jayhawke]

suggestion- after finishing your repair- spray the neck with undercoating - that type of rot was caused by road salt being sprayed off your wheel.- And for the tank/canister- it is faster and easier to raise the bed- 6 bolts- apply head and wind them out- unplug taillight harness- and stand bed up on side or remove.- then carefully brush the top of tank off- bet your have some pinholes there too.

 

[corvairbob]

thanks but the truck will not last long enough to have tis rot out again. i have taken the beds off but i bet if i do this one i will be drilling out the broken bolts for sure. i will not got thru that just yet. if i get the code and or still smell gas then i may go thru that. also at the worst i can just park it outside. i drive it about once a month at most. but lets see how it goes. if i still have the issue i will stop back and update this post. again thanks

 

[corvairbob]

so yesterday i took a mirror and camera and looked at the fuel pump area and aside from it being rusty it did not have the rust scale on it like the filler neck nor id i see any telltale signs of fuel that had sat on the tank area. the hoses looked to be in good shape and nothing broken off so far. so i will replace the filler neck and wait to see if the code returns, it may only time will tell at this point. i do not drive it much but for testing i drive my granddaughter to school a 40 mile round trip so i think a weeks worth of driving her to school with the truck should be enough to give me any codes if they are going to pop up. if after a week of driving i do not get the p0440 code i will call it fixed. and i will stop back and let you know how that turned out. if i have to deal with the fuel pump area i will just cut out the bed and deal with it as if i try to take out those bed bolt i'm betting they will just break and i will have to deal with that. cutting out the bed will be lots easier as i have aliner and worst case i will have to get a chunk os sheet metal to repair that hole. far easier that working those bolts as they are all under the truck and not so easy to get to. thanks

 

[corvairbob]

ok guys i got the part installed and will leave it on the stands for a bit so i can do a smell test the next few days. if when i visit the garage and i still smell gas then something else is bad as well if not then i will take it down off the stands and drive it to take my granddaughter to school days next week and see if the codes come back. i will let you know the outcome of that next week. it took me all of 15 minutes to put that back in, but i did have everything ready, i greased the pipe and hose to allow easier insertion and that went great.

i did spray the plumbing and the top of the fuel pump flange to coat it and maybe slow down any rust for a bit anyway. it will not stop it but get me a few more months or more before it starts up again.

thanks

 

[corvairbob]

ok i installed the fuel filler pipe and that did not fix the issue! so i hooked up the scanner and ran the scans again, and this is what i got for the results of the last scan. i could not do the scanner before the fuel pipe and it failed way more tests, so because i smelled gas i had to at least fix the filler pipe.


name of the test's results of that test
evap purge leak vacuum fail test ok
evap purge leak vapor test ok
evap purge leak pressure test fail
evap nv .020 error test ok
evap nv .040 error test ok
evap weak vacuum test 2 vapor ok
evap weak vacuum test 2 vacuum ok
evap weak vacuum fail test 1 ok
evap weak vac pressure test 1 fail
evap excess vac pressure test 2 fail
evap excess vac fail test 2 ok
evap excess vac test 1 ok
evap canister leak test ok

so the evap purge leak pressure test fail tells me i may have a bad purge sol valve? or i have a leak yet but don't know where, the weak vac test and the excess vac pressure test kind of tells me i may have a bad hose or like some said the top of the fuel pump may have a hole. but i gave the results just in case some here say it is a electrical part and not a hardware part. any ideas are more than welcome. i have to run 1/2 tank out to remove the tank and do more checking or parts repairing unless some say it is the valve on the canister? and not on the top of the tank.

thanks for any ideas on this.bp

 

[Jayhawke]

ok- over the rear axle is your charcoal box with your purge valve- there is rubber lines running to it and back from it.check those and while there tap on the purge solenoid with back of screwdriver- they get stuck.

 

[corvairbob]

jayhawke thanks what i may do is get a new one. being this is 20 year old. but tapping on it would unstick it for sure. and the only reason is i do not want to have to go and tap it again. i did see it when i was under the truck, but because the filler pipe was all rotted out that was the first thing i had to repair. and i figure i would just go one at a time. so now that your talking the evap vent valve i will get one on order and next week replace it. but i have to drive the truck tomorrow and monday so i will give it a tap and see if it frees it up and the tests pass, then i know for sure.

say if i hook up my harbor freight scanner and command the evap to run a test will it run the test or will i have to just let it run the test as it would normally do? i did tell it to run the test today but i did not take the car out of the garage so it may not be able to run it until the cr is actually driving. but i did clear the code so maybe it will run it now automatically. thanks.

 

[corvairbob]

ok i have not drove the truck yet but i decided to just get all the sensors as i believe i will see the code tomorrow mainly because if i have to change 1 i will just change them all. i got the vent, purge and tank pressure sensors now in the mail. i'm betting the code will return tomorrow and so what i will now do is put the truck on the lift try to remove the bed bolts and hope they do not break off then lower the truck down and off the lift. then i have everything in the open to test the lines for vacuum and if any fail i will replace the failing hoses. the purge i may wait till i put it back in the air to marry the bed back to the truck. this way i fully expect to not get the code again as all electrical parts will be new and i will check the lines for damage and replace any i find suspect. then it should be a done deal. also i will do voltage tests to make sure power is going to the valves. if i do get the code again it will just stay there as then i have an issue i just will not be able to get to. i will also pressure test the tank. may do that with a smoke test as that will show me any failing plumbing. thanks and i will let you all know how it goes next week. thanks bp

 

[Straight Success]

I'm chasing my problematic P0440 code now. It's not fun.

 

[corvairbob]

ok i got the thing just about figured out thanks for all the ideas and the help. you saw the filler was rusted out and that was the gas smell. then the code came back so i put it onthe lift and took out the tanl and tested all the compontes. the canister was good the vent was good and then i gound the vent line rusted out at the front by the trans at the connector. so i cut out the connector and sliced in gas line hose and did a vacuum test and it held. i did the tanks at 1.53 pressure and it held for 30 min and i did a smoke test and it did not leak smoke for the hour i ran the test.

i gotr anew vent valve and tank pressure sensor and new purge valve and toorrow i will install the pressure and purge sensors the vent is now new. and i will do a pressure tels at the evap test port and see if it now holds 1.5# fr any amount of tiem. and i may even do a smoke test at that port.

straight success. if your truck is as old as mine and rusted like mine you may find it easier to take the tanks out. have to remove the drive shaft. then the filler pipe and then drop the tank there are a few youtubes on it. if the filler pipe is rusted change that and then follow the purge line from the canister to the front where it turns into a rubber line. mine was rusted at the connector. if you need pictures let me know i have some. of the tank and i can take one of the area where the purge line had the leak.

 

[Rhotpursuit]

Please....please.....please. Proof read your replies before you post them. This was painful to try and read.

 

[corvairbob]

ok i did and it is gone. so now you don't have to suffer. i will not reply with what i found

 

[manbearpig]

Way to stick it to the man there.