Scan error P0455 (Please Help.)
You have an air leak in the system someplace,most likely at the cap,and since it cleared the code for several weeks the first time,it still is the most likely suspect.Had a fuel filter replaced lately?look for loose fittings.
Other then that,you should clear the code after you do the above,you should not notice any driveabilty issues,the system is to keep fuel vapors out of the little air we have left.It should be fixed,a.you wont pass a smog test b.you wont like the cel on all the time.
Dont know where you live but most smog stations can test the gas cap for free on the leak down tester.
If the above does not work,and I think one of them will,you will need to have a smoke test done to locate the leak.
ohlord

"GOT CODES?"
You can buy your own obd2 scanner for 39 bucks at harbor freight tools in n.j. go online to find one near you,or order it online,worth there weight in gold,also autozone or pep boys and the like will read codes for free and save you an expensive trip to the dealer.
Last edited by ohlord; Sep 5, 2007 at 03:35 PM.
take off the rubber hose which runs from the fuel tank/charcoal recovery cannister to the input of the regeneration(purge) valve and put a good squirt of WD40 into the input side of the valve. Re attach the hose. You may have to do this again if the CEL comes back on. These steps fixed my P0455 problems.
I don't know how similar your E420 evap system is to the one on my E430, but the first thing I would check is the regeneration valve for function. It applies engine manifold vacuum to the evap system. On my car it is in the engine compartment on the drivers side, and there is a vacuum hose running to it from the back of the intake manifold, and another that goes to the firewall and ends up at the gas tank. When you pull the vacuum line off that leads to the firewall there should be a pulsing/popping sound as the valve opens and shuts, metering vacuum to the gas tank. If that is good then you either have a leak somewhere, or the charcoal canister shut off valve is bad.
The charcoal canister shut off valve is normally open but closes for the system test that pulls a vacuum on the system to check for leaks. If that valve doesn't seal off you'll get a p0455 code.
What's funny to me is that a faulty regeneration valve is supposed to throw a different code. I changed my shut off valve first but no joy. Did the regeneration valve next, and that fixed it. No vacuum in the evap system during the test for whatever reason will evidently throw a p0455 code. Cherck the source of vacuum first, the regeneration valve. No vacuum to the system makes the computer think there is a leak.
Also, don't fill the gas tank with the engine running. That will throw that code as well I'm told.
take off the rubber hose which runs from the fuel tank/charcoal recovery cannister to the input of the regeneration(purge) valve and put a good squirt of WD40 into the input side of the valve. Re attach the hose. You may have to do this again if the CEL comes back on. These steps fixed my P0455 problems.
Last edited by ohlord; Sep 6, 2007 at 04:28 PM.
In the pic that ohlord provided it is Y58/1. They call it the purge valve. A lot of people call it that, but at the dealer it's called a regeneration valve. Check it out first.
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If it is stuck,you can free it up by pulling off the vac line or both lines and with the aid of a small funnel or a squeeze bulb( for babies ears) filled with seafoam or marvel mystery oil,squirt some into the tubes and the valve,let sit for 15 minutes and hook up the lines and start the engine,after about 15 min repeat the test to hear if the valve is now pulsating.Clear the codes,and see what happens.
ohlord

"GOT CODES?"
It is a little more work to use the seafoam instead of wd40 but I have found it really removes the crud in the lines and valve much more completely and the left over you can add to your next fill up of gas and clean the fuel injectors.
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ohlord
ohlord

"GOT CODES?"
They get stopped up? With what? There should only be gasoline vapors passing through there.
ohlord
I use an old speedometer cable in a drill,however I saw on t.v. last week on the speed channel that some company has a product called snake bit that does the job.Google it -snake bit egr cleaning-
I have the cables,but it looked like it does the job also.
That will clear up your p0400 code,it is rare for the egr to fail and common with that code to be the carbon blockage.
get r done

http://www.benzworld.org/forums/w210...questions.html
read down the post for the instructions
the egr is located back on the pass side below the intake tubing it had a aluminum tube snaking back into the middle upper part of the intake.
cleaning the tube and the carbon out usually solves the p0400 problem
http://www.benzworld.org/forums/w210...questions.html
ohlord
Last edited by ohlord; Apr 13, 2008 at 05:58 PM.
ohlord
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