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Anybody ever replace this when they got a code p0440? If so, which way did you go about replacing? if so, did u have to drop the tank or from cutting from underneath the seat? Is this the same location as from the 1st gen is300? Need to know please!
I had the same code. I bought a new gas cap. And cleared the code. And it came back. I cleared the code again and made sure I didn't top off the tank when filling up. I had to clear the code two more times. And made sure I didn't top off the tank for the next fill up. the code is gone. I would try that before pulling everything apart.
I had the same code. I bought a new gas cap. And cleared the code. And it came back. I cleared the code again and made sure I didn't top off the tank when filling up. I had to clear the code two more times. And made sure I didn't top off the tank for the next fill up. the code is gone. I would try that before pulling everything apart.
When you had this code, was there any pressure build up when opening the gas cap?
Well, I changed the evap charcoal canister and the gas cap and still the same. When I open the gas cap, there is no pressure build up. Also, changed, checked and replaced some hoses on the engine bay.
When you had this code, was there any pressure build up when opening the gas cap?
Well, I changed the evap charcoal canister and the gas cap and still the same. When I open the gas cap, there is no pressure build up. Also, changed, checked and replaced some hoses on the engine bay.
I think there was pressure build up when I took the cap off. I can't really remember
Also check your fuel vapor feed pipe (little plastic box on top of engine near dip stick).
As the rubber hoses stiffen from age and heat they will lose elasticity. The hose connected to this little box was not well designed in shape and as it stiffens it can snap the neck off the fuel vapor feed pipe, which will throw the error.
Also check your fuel vapor feed pipe (little plastic box on top of engine near dip stick).
As the rubber hoses stiffen from age and heat they will lose elasticity. The hose connected to this little box was not well designed in shape and as it stiffens it can snap the neck off the fuel vapor feed pipe, which will throw the error.
I have checked, replaced hoses from the engine bay. Also, replaced the evap canister with a used unit with vapor sensor and gas cap. When I bought the car about almost a year ago, there was no pressure build up when went to go put in gas. I'm thinking it's possibly leaking from overfill check valve. Does anybody had to replace one of these? I have read on other lexus models and had this problem with this p0440 code.
Well, I decided to cut open from the top with a cut off tool where the overfill check valve is.
I inspected the valve and what do you know, there was a hairline crack on top of the check valve.
I decided to use some jb weld and test drove for about 30-40 miles or so. After test driving, I opened the gas cap and there was some pressure released. I'm thinking it's fixed, but need to drive some more miles to be sure. Before all this, I scanned the evap with my techstream scanner and the reading was low on the pressure. After upon fixing the check valve and test driving, I came back to retest with the scanner and the reading was totally different. I'm seriously hoping this repair fixed my p0440 issue. Will update after some more driving and see if any codes appear.
Yes, I've had a hose nipple snap off that little black cannister. JB weld fixed it for about 3 months and just to be safe I spent a few dollars for a replacement. I"ll bet that particular code is the most common code that pops up on the SC430
No pics. I just removed the back seat and cut it and made a access door to the check valve. I inspected the top cap and there was a crack around the seam. That was the culprit for my p0440 issue. I have replaced the whole evap canister with the pressure sensor and solenoid with a used working unit too before this. Now I think it's fixed, since now there is some pressure build when opening the gas cap. Before there were no pressure. Hope this fixed my issue.
I know this is an old thread, but I just replaced my overfill check valve from the top and I thought I'd share a few pictures. Hope this will help others with where to cut the opening. Cut out made, check valve pried out. Old check valve out, crack along the top. Cause of all the gas odor outside the car. All buttoned up with new check valve, sealant and aluminum tape.
I know this is an old thread, but I just replaced my overfill check valve from the top and I thought I'd share a few pictures. Hope this will help others with where to cut the opening. Cut out made, check valve pried out. Old check valve out, crack along the top. Cause of all the gas odor outside the car. All buttoned up with new check valve, sealant and aluminum tape.
04-10-15, 09:30 AM
Fuel overfill check valve?
