Causes and Fixes Chevy P0455 Code: Evaporative Emission System Leak Detected (Gross Leak / No Flow)

How to fix a Chevy or GM P0455 engine code: Evaporative Emission System Large Leak Detected
How to Test a Purge Valve
• How To Test Evap Purge...
Link to Smoke Machine: amzn.to/41U0Dif
Possible Causes of a Chevy P0455 Code:
Gas Cap
Evap Leak
Purge Valve
Vent Valve
Evap Canister
Wiring
Fuel Tank Pressure sensor
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[@michaelrenda747]

Excellent video! My aftermarket gas cap, only 4 months new, was the cause of the P0455 error code because of the gas cap no longer maintained a proper seal on my 2009 Silverado. A new OEM gas cap solved the problem.

[@JoseHernandez-lm3hs]

Best video I have seen about this topic.

[@nelsod76]

Thanks. Exactly how I like a video. Explain the system operation so can troubleshoot. To the point. I have a 2012 Tahoe with this code for a few weeks and started to leak fuel. Found the elbow on the fuel pump had rusted out. I am feeling fairly certain that will be the cause of the code but have yet to finish replacing the pump to verify.

[@matthewrick]

Great video. Love hearing you say “shivvy”

[@cruzvcruz5752]

You explained this perfect thank you

[@blahblahhhh2801]

Good simple video

[@abh114]

Very nice video good info ,Thk you

[@duanerykhus9425]

Thank you vary helpful :)

[@fireadept007]

I swear it sounded like you're saying 'shitty silverado' lmao great video. currently fighting 4 codes on my tahoe, fingers crossed. I'm getting p0030, p0053, p0455, and p0496 and I can smell gas when it's running.

[@grominwithrob1339]

My gmc Sierra throws this and will leave a small 5”-6” wet spot under the filler neck. Everything is bone dry except the tank. The amount of gas makes me think a line has a small leak under pressure. It drains a tiny bit until it’s not under pressure. I haven’t been able to confirm this yet but it seems right since time and fuel level doesn’t dictate amount of fuel that leaks. It’s always the same amount. If it sits longer, the little spot evaporates so it doesn’t seem to be a continual leak. I’m thinking a small hole in a line above the tank. Hoping it’s a fuel line and not a pinhole on the plastic pumps line connections where they weld the two halves together.

[@everetteroberts9547]

Very helpful vid.....

[@miguelamigo6030]

Very informative video

[@Gomezal80]

good schematic. thanks

[@DTA555.]

Mine is the gas cap it is a different Type of fuel pipe going to the gas tank, so my gas cap busted and it fits way too tight. I had to pry it off with a screw driver because it would not come off. I was checking to make sure that I was correct thank you

[@user-rs9iv6jr8o]

So where would the canister purge valve be located on a 05 impala LS

[@iAmSantiCruz]

its was my gas top . it was open. how long for the icon to disappear.

[@k.bellingham8335]

Quick, concise and to the point, thank you. Questions; You mention when the purge valve opens or closes, what about the cannister vent valve? Is it always open except when the computer tests the system for leaks? And how often does the computer test for leaks?

[@HVAC_Mechanic]

The vent valve is normally open until closed by the computer. It varies between vehicles when the computer tests the system. Often, it is 2-3 hours after the vehicle has been shut off.

[@k.bellingham8335]

Thank you,@@HVAC_Mechanic

[@noahjayden6684]

The thing is were does the purge valve go ecacly

[@tobyfriddle9919]

Does this affect starting. When I first get in to start, it hesitates to start after that initial one it starts easily unless it sits for a couple hours

[@HVAC_Mechanic]

Usually, the Evap system does not affect starting unless the purge valve is stuck open. If the purge valve is stuck open, it can let gas vapor into the engine, which can cause start issues.

[@howardsupples]

Sounds like yours could be the crank sensor. I had that issue once before with my 07 tahoe

[@samuelgarza9812]

I’ve replaced the purge valve 2 times on a Chevy traverse 2018 and the code po455 came out again last night I ordered the emission canister purge tube. I’m thinking it might be leaking but at this point I’m just guessing it’s the cheapest repair.

[@donadams1404]

Same thing happening 2 my 2018 traverse I first got code p0442 2 weeks ago shop did a smoke test n said it was the canister purge valve I replaced n Saturday my check engine light came bk on. I took it 2 auto 2 scan code n got p0455 n was told it was fuel tank pressure sensor

[@samuelgarza9812]

Does yours hesitate when you accelerate? Mine does. did that fix your problem?

[@josephmore7537]

Did you get the P0455 code to clear and if you did what was replaced? My 2018 Chevy Traverse is doing the same thing after replacing the purge valve and ftp sensor.

[@samuelgarza9812]

@@josephmore7537 my code po455 went away BUT it’s running rough at idle . So I’m replacing the spark plugs today I’ll let you know if that works

[@cruzvcruz5752]

@@samuelgarza9812how did changing your spark plugs go I changed mine on the Chevy Cruze bc I had a burnt injector

[@gallero2725]

2018 Chevy traverse, do you know where that FTP is located… I check ok tha gas tank and is not there…

[@donadams1404]

Need 2 know the same thing

[@josephmore7537]

It's located on a fuel line coming from the fuel pump on top of the gas tank

[@saidflores81013]

@josephmore thanks

[@johndelconte9915]

Does the PO455 code require a reset or will the check engine light go off when the problem is fixed?

[@HVAC_Mechanic]

Once the problem is fixed, it will likely go off eventually on its own; when it goes off, it depends on the computer. Usually, the code is cleared with a scan tool. It can be cleared by removing a battery terminal for 2-3 minutes, but any settings in the vehicle will be lost. Automotive stores will often come out and scan or clear codes for free.

[@johndelconte9915]

@@HVAC_Mechanic I followed your advice and when I went under the vehicle to check the wires and hoses at the fuel tank there were leaves and acorns on the tank. This is a motor home so it isn’t driven every day. I pushed the connectors in tight and checked the hoses and cleared out the debris. When I checked, the check engine light was off. I been starting it occasionally and it’s still off. I wasn’t sure if the light would have gone out so fast. Is that possible or a coincidence? I need to find way to keep rodents (chipmunks) off the tank.

[@johndelconte9915]

@@HVAC_Mechanic I thank you for getting back to me so quickly

[@mwiebz1]

I have this code with a strong smell of gas . Any idea where to start?

[@johnmacaulay7463]

I just had the same code, drained the oil in my 2012 impala and it stunk of gas. Somehow there was gas getting into the oil so you may want to check that out

[@ImpalaSS08]

I’ve replaced the vent valve, the purge valve and the gas cap. I only get the P0455 occasionally after fueling up and first start there after. What’s up? Please help. Thanks

[@nome7499]

Make sure you turn the gas cap 3 clicks, i just filled up also and this code just got thrown the day after so i’m pretty sure that’s what i’m issue is too

[@ImpalaSS08]

@@nome7499 I do that every time but thanks.

[@ScrewedEquilibrium]

You might have a issue with the LDP giving a false reading if the PCV and vent valve solenoid holds vaccum and there is no actual gas vapor leak then it's the LDP. ALSO NEW PARTS IN THE CAR WORLD NEVER MEANS NEW THEY CAN ALREAFY BE BAD OFF THE SHELF Edit the traverse doesn't have a LDP so one of you Solenoids is bad or you have an actual leak

[@ImpalaSS08]

@@ScrewedEquilibrium mine is a 2.4 HHR but thanks for the suggestions.

[@jayvian327]

Any luck I have changed nearly the whole evap and I am still getting this code?

[@jdtv...9134]

Ismoke tested my Chevy HHR no leaks but still have a p0455

[@Nickolision]

Same issue on my 97’ eclipse. I’ve checked my DTC monitors via Torque Pro. EVAP monitor always completes first and the code will always show after a little while. Let me know if you solved this.

[@jdtv...9134]

@@Nickolision I have to drop the tank which I've yet to do.. Sorry I didn't see your comment sooner

[@proroofersncllc-vb8rl]

Did you fix?

[@j_S0VEREIGN]

This code in coming on my HHR. gas cap is good (I think) I bought it brand new last year. I’ll have to check the other things mentioned.

[@lohostege]

So a fuel tank leak is probably the cause of this

[@johnellisonarmadilloconstr7966]

Sha-ev-e

[@lee28.78]

Can this cause your car to stall and shut off

[@HVAC_Mechanic]

If the purge valve is stuck open it can cause issues, but otherwise it doesn't affect the engine.