EVAP system small leak
Thread Starter
Melting Slicks
Joined: Aug 2003
Posts: 2,786
Likes: 7
From: Iowa
EVAP system small leak
I think the code I got was P0442 C H if I remember correctly, description is EVAP system small leak, aparently there is a different code for major leak! anyway, my car's got it, what do I do?
I cleared it out and it came back about a week later. I'm wondering if something didn't get put back together properly after I had Ed do a UDP, cam and tune on it. I e-mailed him about this when it first happened but haven't heard back, I'll have to try to contact him again now that its happened twice. is this something which I may be able to find and fix easily? what should I look for? Any help would be appreciated!
I cleared it out and it came back about a week later. I'm wondering if something didn't get put back together properly after I had Ed do a UDP, cam and tune on it. I e-mailed him about this when it first happened but haven't heard back, I'll have to try to contact him again now that its happened twice. is this something which I may be able to find and fix easily? what should I look for? Any help would be appreciated!
Burning Brakes
Joined: Jul 2006
Posts: 968
Likes: 12
From: Regina Sask
First check that the gas cap is clicked on tight. Also check to make sure that the gas cap seal is in good shape. Then try a new gas gap.
I've also had leaking EVAP vent solenoids (on the inside right frame rail by the trans). They are about $45.00 CDN.
Russ Kemp
I've also had leaking EVAP vent solenoids (on the inside right frame rail by the trans). They are about $45.00 CDN.
Russ Kemp
Thread Starter
Melting Slicks
Joined: Aug 2003
Posts: 2,786
Likes: 7
From: Iowa
Thanks for the help!
from the service manual I guess the car pressurizes the fuel tank to prevent evaporative emissions from leaking out to the environment. if it pressurizes the tank and the pressure falls too fast it throws the code saying there's a leak. I'll check the fuel cap. I'm almost out and need some fuel today anyway. if that doesn't work how serious is this problem anyway? fuel evaporating isn't going to make any kind of noticeable drop in fuel economy since the amount evaporating its negligible. I know that fuel vapor is flammable, but I don't think we're talking about much at all.
so I guess my question is is this a dangerous kind of thing? if it doesn't fix easily by tightening the fuel cap or even replacement can I just have my tuner turn off this particular code and just ignore it?
from the service manual I guess the car pressurizes the fuel tank to prevent evaporative emissions from leaking out to the environment. if it pressurizes the tank and the pressure falls too fast it throws the code saying there's a leak. I'll check the fuel cap. I'm almost out and need some fuel today anyway. if that doesn't work how serious is this problem anyway? fuel evaporating isn't going to make any kind of noticeable drop in fuel economy since the amount evaporating its negligible. I know that fuel vapor is flammable, but I don't think we're talking about much at all.
so I guess my question is is this a dangerous kind of thing? if it doesn't fix easily by tightening the fuel cap or even replacement can I just have my tuner turn off this particular code and just ignore it?
Thread Starter
Melting Slicks
Joined: Aug 2003
Posts: 2,786
Likes: 7
From: Iowa
I fueled up the car and made sure the cap was tight, I guess it will take about a week or so of normal driving to see if that code comes back. with all the electronics in a C5 you would think they could put a notice on the DIC that your cap is loose, just like door ajar etc. oh well.
I inspected the cap and did notice a lot of cracking in the seal in the cap. it pretty much looks like any piece of rubber which is exposed to heat, freezing temperatures, water, dust fuel etc for 7 years. if the code comes back I'll replace it.
thanks for all the help!
I inspected the cap and did notice a lot of cracking in the seal in the cap. it pretty much looks like any piece of rubber which is exposed to heat, freezing temperatures, water, dust fuel etc for 7 years. if the code comes back I'll replace it.
thanks for all the help!
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Burning Brakes
Joined: May 2003
Posts: 1,234
Likes: 427
From: LI NY
So you’re roasting me because I’m new? Wow. This forum is really welcoming. 😂 im glad the previous guy commented on this old post as it helped me immensely during my search for my issue. As an old grouchy member you’re probably used to telling the newbies “USE THE SEARCH TOOL!” haha. Just kidding buddy. Happy thanksgiving.
