Evap 442 - 2005 chev blazer 4.3 L
 

hi guys,

My truck had a bad evap unit on intake manifold and I only had that one code. I had hard starts etc. No other codes present in system. No leaks


I replaced the unit and this addressed the hard starts and cleared the code for faulty evap part on intake manifold.

I then received the small leak code.

I must of done something when installing it.

So you know there was no gasket with replacement part.

I just put it on and tightened it down. fully put the line back on and clipped in place.

There is a small green round valve up the line which I assume can vent the gas should one care too.

I doubt I damaged the line with a pin prick actual leak. Must of been something I did when I installed it.

Starting issue fixed and code cleared for broken evap part soooo.

Any ideas?

Thanks guys, love this forum.

Wrong section?

that valve with the green cap is for smoke testing the evap system. it could be something you did or some other part of the evap system just coincidentally decided to leak. even a cracked seal on your gas can can throw that code. without a expensive smoke machine i really dont know how to test for a small leak

I haven't tried this but it might work. apply a very low pressure air source of around 1PSI, and a spray bottle of water with a bit of dish soap might work. Spray it on suspect locations like fittings, gaskets and gas cap. Look for bubbles. This is how you would check for natural gas leaks on house plumbing.


There should be only a few places you need to check.

Ok cool I didn't know that re: green valve. So to ensure its closed , turn it righty tighty (clockwise ) to ensure it's not leaking through there? I know dumb question but it verifies it is something that open and closes. Does the green thing come off and the smoker attach to it while the hose is still hooked up to evap device?


Thanks guys, I like the soap idea. I saw a crazy video online of a guy who used a cigar to blow smoke into the line then pressurize it.

i did smoke test using machine, found scrape in hose to charcoal canister via fuel tank that sat on rusted frame, finally! fixed scrape hole, no more evap code.. purge valve and solenoid valve all operational! had to use smoke machine!!!!