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Dr. Hamman
Dr. Hamman, Automotive Engineer
Category: Car
Satisfied Customers: 6286
Experience:  30 years experience, Repairing, building, & designing, automobiles.
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2003 hyundai sonata gls: evap..replaced fuel..vacum leaks..light comes

Resolved Question:

i have a 2003 hyundai sonata gls it has obd11 code p0455 evap large leak. I have replaced fuel cap,replaced sensor asm,valve can and checked for vacum leaks but still the ckeck eng light comes on with the same code (P0455). can you tell me what to do ?
Submitted: 8 years ago.
Category: Car
Expert:  Dr. Hamman replied 8 years ago.

Hi, I will do my best to assist you. When you are finished please click on accept. I don't get paid unless you do. I don't know if you are a pro or a novice so we may have to fine tune the answer.


You may want to use a little low pressure air in the system to locate the leaks. Low pressure is important, also unhook any sensors, and try it with the ignition off. These systems can be tough to find a leak in, and blowing a little pressure into them can normally help you to spot any leaks. If you have any more questions I am here to help. Good luck, and Thanks for using Just Answer.

I hope this helps, 100% satisfaction is my goal. If the answer is not clear, please reply and I will assist you more. When you're satisfied, click on accept. I don't get paid unless you do. A bonus and positive feedback are always appreciated, good luck and Thanks.
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