code p0455 problem
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code p0455 problem
I recently had my sending unit/fuel pump replaced because of a gas leak at fill up and my gas gauge didn't work. Fixed both issues - they dropped the gas tank and reused all the old hoses - said they looked good. I had a p0455 code before the repair but thought fixing the leak would fix that too. It didn't. They said it could be the canister but the hose coming off it looks good. Can the canister itself be bad? Can I use the purge control solenoid service port to troubleshoot this? How else can I troubleshoot? Can't find any cracked hoses but the hose coming off the intake is very slightly loose - easy to pull off and has a rough texture to it. You can rub it between your fingers and it leaves a lot of black residue on them. One final thing. They replaced a bad 02 sensor and charged me 89$ for it - said is was OEM. Is that a reasonable price? Labor was good at 20$ to replace. thanks once again
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From: SW Va
P0455 = Gross vapor recovery system leak. Seeing as how you had this problem Before the recent work, sounds like the work not being properly completed isn't the cause.
I agree the deteriorated loose fitting hose you found belongs on your suspect list, as does a faulty gas cap, or fuel inlet hose or their seals to the gas tank.
If you can't find an obvious problem visually, try a smoke test, to see if you can spot the leak that way.
More thoughts for consideration, let us know what you find.
I agree the deteriorated loose fitting hose you found belongs on your suspect list, as does a faulty gas cap, or fuel inlet hose or their seals to the gas tank.
If you can't find an obvious problem visually, try a smoke test, to see if you can spot the leak that way.
More thoughts for consideration, let us know what you find.
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From: SW Va
https://www.justanswer.com/ford/6xlh...cuum-leak.html
If no machine, seeing as how the code is for a gross leak, set up the above test scenario & come by a Swishers Sweet cigar & blow smoke into the questionable line, or test port as instructed, until it exits the open gas cap. Install the cap & continue to blow smoke into the system while your helper looks & sniffs for leaks & let us know how it goes.
If you've been smelling gas fumes, begin looking in the area where you've noticed the strongest gas fume odors.
Be careful with the cigar around gas fumes, we don't want to read about it in the paper!!!!
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I decided to check gas cap before doing smoke test - it sounded iffy to me. I cleared the code by disconnecting negative battery cable and then I taped off gas cap with duct tape to make an airtight seal. Simplest things first! I have gone over 100mi. at least and the code has not returned. The cap looked fine and clicked when turned clockwise but it could be "rocked" slightly from side to side - seemed a little loose. Also I couldn't get it to click so that the arrow on cap would end up or start at the 12 o'clock position like the owners manual says consistently - is that critical by the way? The cap has always been in the back of my mind for some reason. Comments please
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From: SW Va
The gas cap is part of the vapor recovery system & is designed to breathe & lower negative tank pressure when it reaches it's set point, so the tank won't collapse, or the system not be able to pull fumes from the tank, or the fuel pump to be able to pull fuel from the tank.
SO, yes the gas cap is an important vapor recovery system item & if it's faulty, it's recommended it be replaced with a OEM part.
SO, yes the gas cap is an important vapor recovery system item & if it's faulty, it's recommended it be replaced with a OEM part.
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If 100+ mi. is enough to reset the code then I will get another cap because that proves the old one is bad. I don't like to throw parts at a problem. That's a waste. I didn't realize that the cap automatically vented at a certain set point. I thought it just sealed the filler neck air tight and that was all. I will remove duck tape as soon as I get a cap as that seems to be a bad long term idea. Can I get an OEM cap at parts place because there isn't a Ford dealer in the county anymore I don't think. What about arrow orientation of cap? thanks pawpaw Details are essential!
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From: SW Va
If you had a 100% tight seal on the gas cap fitting with your duct tape, the engine would probably have stalled in the 15-20 mile/20-30 min time range, from the fuel pump removing fuel to run the engine, thus pulling a tank vacuum it could no longer over come.
It's happened to other Ranger owners when their gas cap failed, or they used aftermarket caps. I also know of one Tacoma owner on the old MotorWeek forum that suddenly began having stalling problems after a 20-30 minute drive from a non venting gas cap. When it stalled next time I suggested he pull over, jump out & loosen the gas cap to equalize tank pressure, then immediately try restarting the engine, he got a positive test response, he said a new OEM gas cap put that problem right.
I've read the vapor recovery system can detect as small as a .040" system leak, so it's sensitive.
I don't know what size problem it takes for the system to set the P0455 "Gross Leak" code!!! lol
Let us know what you find & how it goes.
It's happened to other Ranger owners when their gas cap failed, or they used aftermarket caps. I also know of one Tacoma owner on the old MotorWeek forum that suddenly began having stalling problems after a 20-30 minute drive from a non venting gas cap. When it stalled next time I suggested he pull over, jump out & loosen the gas cap to equalize tank pressure, then immediately try restarting the engine, he got a positive test response, he said a new OEM gas cap put that problem right.
I've read the vapor recovery system can detect as small as a .040" system leak, so it's sensitive.
I don't know what size problem it takes for the system to set the P0455 "Gross Leak" code!!! lol
Let us know what you find & how it goes.
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From: SW Va
If interested, you can read more about the Evap System monitor here http://www.fordservicecontent.com/fo...t/obdsm99b.pdf
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According to the printout Auto Zone gave me after they read the codes the leak is 0.080", large leak detected. Printout also says "gross leak or no flow for a predetermined period of time" and "most likely solution is inspect for loose fuel cap and tighten or replace as necessary". I will read the link you sent. I guess I will throw this part at problem. This is just info for you. thanks again pawpaw
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From: SW Va
According to the printout Auto Zone gave me after they read the codes the leak is 0.080", large leak detected. Printout also says "gross leak or no flow for a predetermined period of time" and "most likely solution is inspect for loose fuel cap and tighten or replace as necessary". I will read the link you sent. I guess I will throw this part at problem. This is just info for you. thanks again pawpaw
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I removed the duck tape expecting the code to return but it's been thru another tank of gas without returning so I hope I'm ok. Could the code have been set twice and come up again without their even being a problem? Glad I didn't get another gas cap - that's why I don't like to throw parts at a problem. Thanks for the help pawpaw. I consider this issue fixed but have another I'm fixing to write up.
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Spoke too soon! Code returned the very night I made my last post. Got a new cap at AZ and they reset code. See if that works. If not I will replace that iffy hose I talked about in post #1. Kind of forgot to do that. What is the failure mode of the cap anyway. The sealing surface on mine looked fine- do they fail internally? thanks again