Got the P0455 Code on My Chevy Tahoe, Need Help!

Chevrolet Models Chevrolet Tahoe
21

Don’t overlook the charcoal canister. If it’s damaged, it could also trigger the P0455 code. I had to replace mine.

22

You’ll need a ratchet set and possibly a torque wrench if you want to be precise.

23

Just want to chime in with my experience. I replaced the gas cap and cleared the code, but it returned. Sometimes it can be tricky!

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24

No, I hadn’t. I’ll go check that next. Thanks for the heads up!

25

Definitely check the vent valve! It was the issue for my Tahoe. They can be tested with a multimeter if you’re handy.

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26

I once had a P0455 code and my mechanic used a smoke machine to detect leaks. It’s super effective but might cost a few bucks.

27

Sometimes you can make your own leak detection kit using soapy water and a spray bottle. Just spray it on the lines and watch for bubbles!

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28

If the code keeps coming back, you might need a new gas cap, but don’t forget to reset the ECU afterward!

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29

Great advice, everyone! I’m feeling hopeful now. Can too many misfires trigger a P0455? Just curious.

30

Sometimes, the ECU can throw a P0455 if it’s seeing strange readings from other systems. It’s worth having a full system check.

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31

If we all put our heads together, we’ll solve this! It’s like the Avengers of car repairs here, haha!

32

I had the P0455 code on my Tahoe last year! It turned out to be a loose gas cap. I just tightened it and cleared the code. Super simple fix!

33

That’s good to know! But if that’s not it, you might want to check the purge valve. They can fail and trigger that code too.

34

I’ve dealt with this code before! After a lot of troubleshooting, I replaced the EVAP canister. It cost around $200, including labor.

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35

That’s a good option! Did you DIY or have a shop do it? I’m wondering about costs.

36

I had a shop do it. They mentioned the parts were a bit pricey, but the labor was reasonable. Make sure to shop around to get quotes!

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37

Good advice! I’m getting quotes tomorrow. Fingers crossed it’s not the fuel tank. That could be a big job!

38

Have you checked for leaks in the EVAP system? Sometimes, small cracks in the lines can lead to this code too.

39

Haha, tell me about it! But if it’s just a hose, you’ll save a ton of money!

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40

I would definitely recommend getting a smoke test done. It’s a surefire way to spot leaks in the EVAP system.