There is gas leaking around the gas cap in my 2006 Toyota Highlander. It is not the original cap; replaced it due to an alert "Fuel Lid Open". I do not top off my tank. This has never happened before

you have a leak is my guess. check for any fuel leaking under your hood and replace anything damaged or worn out seals before you have a fire

Many possibles, but first check gas cap for torn gasket or just being loose. The VSC light is related to emissions issue and can be leaking vac hose, bad purge valve and other such.

anything is possible, check codes...

This model does not have an external fuel filter, there is a permanent fuel filter inside the gas tank that is not serviceable unless you want to remove the gas tank.

P0442 and P0456 are both evaporative emission error codes due to a small leak. The most common cause is a leaking gas cap or hose leak on that system. I did not list a code for your 0513. I am sending you a little information about your problem.. Best of Luck to you..


2003 Lexus RX300 3.0L 2003 Toyota Sienna 3.0L 2003 Toyota Highlander 3.0L, Eng Cfg V6, Eng Des 1MZFE, USA/Canada 2004 Toyota Avalon XL 3.0L
Check engine light is on with trouble codes P0442 and P0456. The codes are evaporative system small leak codes.
1. Verify that the gas cap is a factory Toyota gas cap and visually inspect that all hoses and lines are tight and connected.

2. Locate the canister closed solenoid and the vacuum switching valve on the canister. Manually ground them and verify that they operate and function. The canister closed solenoid is normally open and should close when grounded. The vacuum switching valve on the canister is normally closed and needs to open when grounded.

3. Verify that the hoses are not loose or pulled off the canister closed valve on the air cleaner housing. This has been a common problem on some models.

4. If no problem is found, the next step is to ground the canister closed solenoid and the vacuum switching valve under the vehicle and simulate an evaporative test and verify that the system holds a vacuum and functions normally. When the solenoids are grounded, back probe the Blue/Black (L/B) wire on the pressure sensor, and with no vacuum or pressure, the voltage should read around 3.3 volts. Start up the vehicle and turn on the purge vacuum switching valve and use engine vacuum to draw down the system to around 2 volts on the pressure sensor. If the voltage does not increase rapidly, there is no problem. If the voltage increases quickly, look for the leak in the evaporative system. Potential Causes: Canister Closed Valve
Disconnected Canister Closed Valve (CCV) Hose
Gas Cap
Harness
Vacuum Switching Valve - For the pressure sensor.

There is not a lot due at 60,000 miles as far as regular maintenance. Depending on which engine you have, a timing belt replacement is due at 90,000 miles. (The 2.4L engine is chain-driven) Spark plug replacements are not due until 80,000 miles.

In the meantime, I would have the condition of the engine coolant checked. It should be checked for the freeze protection level as well as the acidity level. Chemical test strips are available at your local parts store for this purpose.

All fluids should be checked for proper levels inlcluding differentials and transfer cases if it is a 4X4. Check and fix any fluid leaks right away. Fluid leaks can lead to rapid deterioration of rubber mounts and hoses as well as damage wiring harnesses and computer sensors.

If the battery is original it should probably be replaced due to the age of the vehicle. If it is not original I would have it tested. Remember NOTHING works on your vehicle without the battery.

Hi, I believe this to be due to the loss of "fuel tank pressure". This was designed so that gas vapors are vented to the engine and does not leak out to the open atmosphere. How long have you had this problem? Most likely, I would say it would be a faulty gas cap not sealing correctly. Other possibilities include leaks from fuel tank hoses or evap hoses. There are also valves (i forget the name) that need to be checked too. It's like valve solenoid or solenoid valve.
Leaving your car on while filling up your tank can cause this too sometimes. I would start with the inspection of your gas cap, drive it around for awhile, and see what happens. Hope this helps!

i would chande the plugs at or around 60,000 to 70,000 miles. this is about the correct mileage. they may last longer but not worth the expensence of converter damage due to misfire and also gas mileage loss.

Is this the original gas cap for this vehicle? I have ran into this issue before with some cars when people change the gas cap to a locking one. The original has certain vents that is crucial to operation. If it is the original gas cap, then your fuel tank pressure sensor could be faulty.

turn it to the right and it just clicks? Turn it to the left and it won't turn, right? Well put some muscle into it and make it turn too the left, your dad undoubtedly turned it abot 5 clicks past stop and it's just tight. It will turn, Good luck.