I had the P0440 code pop up on my Silverado too! It turned out to be a loose gas cap. Always check that first before you dive deeper. Simple fix!
That’s a great tip! I didn’t even think about the gas cap. I went straight to the EVAP canister, which was a hit to my wallet. Anyone else have suggestions for DIY diagnostics?
Hey everyone! Just to chime in, I had the P0440 and my mechanic replaced a cracked EVAP line. Costs can vary, but I used a vacuum pump to test the system myself before going to the shop. Saved some bucks!
Nice approach! I’m considering trying that. What vacuum pump model did you use, and was it easy to do?
I went through a similar struggle, and it’s frustrating how many things can trigger that code! For me, it was a faulty purge valve. I’d recommend checking those valves first. Doing it yourself can save a lot of cash!
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That’s the beauty of these forums! So much shared knowledge. Just be careful not to rush into repairs without really diagnosing first, or you could end up replacing parts unnecessarily. Keep it methodical!
Agreed! I rushed to replace an EVAP solenoid once and it turned out to be nothing. Any recommendations on tools that can help with diagnostics?
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Try getting an OBD-II scanner! It really helps pinpoint the issues more accurately. I picked up one for under $50, and it’s paid for itself multiple times over. No more guesswork!
Definitely on my list! I love using tools that provide instant feedback and make the repair process smoother.
Honestly, working on the Silverado has its ups and downs. Just the other day, I found myself under the truck in a rainstorm, cursing the P0440 code! What a day! But when you fix it, the satisfaction is worth it!
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