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cartech, ASE Certified Technician
Category: Car
Satisfied Customers: 3332
Experience:  25 year as shop owner and ase master tech also certified body tech
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Service engine light soon...old gas cap light..emissions issue..code.

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I still have my problem. Service engine light soon. changed an old gas cap light didn't go out.
Where can I locate the other items that may be an emissions issue to cause the light to come on with P440 code.
I was told that after 40 starts the light would go off, it didn't. How can I tell if the problem is solved with the new gas cap if the light doesn't go off. Thanks
the only way to be sure the problem is not still there is to get the codes cleared but it is most likely not fixed only about 10 percent of the time the gas cap fixes it what i recommend is that you get the system smoke tested this will 100 percent tell you where the problem is it can be a vent valve purge solenoid or even a bad filler neck or hose so the test is very important so you don't waste money on uneeded parts

Edited by cartech on 7/1/2010 at 11:52 AM EST
Customer: replied 7 years ago.

How much does a smoke test cost and where can I get one?

most auto service centers can do it we charge 49.95 for it
Customer: replied 7 years ago.

How can I clear codes so I can see if gas cap solved problem before I spend $49.95 that I really can't spare?

Auto Zone cannot do it

you will need to go to someplace that has a code reader clearer auto zone may have one they don't charge
Customer: replied 7 years ago.
Auto Zone says they are not allowed to clear codes. Is this true or are they just being not so helpful?
i can't say for sure i have never used them just know they have the reader any local service should clear them just tell them you left the cap off and need the code cleared they shouldn't charge you much
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