Check Engine Light Code P0442
Senior Member
Joined: Sep 2008
Posts: 468
Likes: 23
From: Los Angeles
2005 C230 Sport Coupe
The purge valve could be checked by re-moving the valve and putting power and ground to the terminals and it should click, like solenoid.
You might want to put a resistor in line with the power to check the valve at less than 12 volts.
Thanks,
Dave
Thread Starter
Member
Joined: Nov 2005
Posts: 121
Likes: 0
2007 cls63 AMG
Yes i am resetting the light everytime. Can someone please check something for me so that i can be sure i am on the right track. After driving the car for 10 minutes or more, when you open your gas cap up to put in fuel, do you guys/gals hear an audible vaccumm whoosh?
I am pretty sure i used to hear it before this problem started happening. If that is the case then i have three possible options
1) the vaccum line from the fuel filler to the EVAP canister is leaking or the fuel filler itself is leaking air.
2) the evap canister cannot hold a vaccum or the shut off valve to the canister is not opening to let anything pass through from the tank to the canister.
3) the purge valve is not pulling anything from the canister either because it is not opening or there is a leak in the vaccum line between the canister to the valve or from the valve to the intake manifold.
Here is another one of my stupid ideas, please let me know why this will not work.
If i bypass the shut off solenoid valve on the evap canister. What i mean is connect a vaccum line from the fuel filler neck to the purge valve, leave the shut off solenoid electronically plugged in. Let the engine run for 10 minutes. If i open up the gas cap after that, if i get a whoosh, means my shut off solenoid is bad.
If i still dont get a whoosh,
If i leave the purge valve plugged in so that the ecu does not detect its un-plugged. Connect a vaccum line straight from the bottom of the evap canister to the intake manifold (essentially bypassing the purge, so i am purging all the time). If i do this for 10 minutes, open up my gas tank and hear a whooosh, it means my purge is not working right.
I am pretty sure i used to hear it before this problem started happening. If that is the case then i have three possible options
1) the vaccum line from the fuel filler to the EVAP canister is leaking or the fuel filler itself is leaking air.
2) the evap canister cannot hold a vaccum or the shut off valve to the canister is not opening to let anything pass through from the tank to the canister.
3) the purge valve is not pulling anything from the canister either because it is not opening or there is a leak in the vaccum line between the canister to the valve or from the valve to the intake manifold.
Here is another one of my stupid ideas, please let me know why this will not work.
If i bypass the shut off solenoid valve on the evap canister. What i mean is connect a vaccum line from the fuel filler neck to the purge valve, leave the shut off solenoid electronically plugged in. Let the engine run for 10 minutes. If i open up the gas cap after that, if i get a whoosh, means my shut off solenoid is bad.
If i still dont get a whoosh,
If i leave the purge valve plugged in so that the ecu does not detect its un-plugged. Connect a vaccum line straight from the bottom of the evap canister to the intake manifold (essentially bypassing the purge, so i am purging all the time). If i do this for 10 minutes, open up my gas tank and hear a whooosh, it means my purge is not working right.
Thread Starter
Member
Joined: Nov 2005
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2007 cls63 AMG
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Good luck
Last edited by Glyn M Ruck; Oct 19, 2009 at 07:34 AM.
Newbie
Joined: Feb 2010
Posts: 3
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05 c230
(I dont have a coupe.)
Can you remove the fuel filler neck on the sedan with the same procedure?
I fuc*en hate my check engine light.
I just wasted $350 dollars, so that the dealership can change my stupid purge valve.
Im sure it only took them 5 min to change. The light came back on the day after.
I hate the dealership.
Well now they are telling me its the fuel filler neck.
I would do the work on my car, but I have never worked on mercedes vehicles.
I dont want to mess something up and regret it. Its not a dodge or Chevy.
Well this sucks.... I dont know what to do?
Can you remove the fuel filler neck on the sedan with the same procedure?
I fuc*en hate my check engine light.
I just wasted $350 dollars, so that the dealership can change my stupid purge valve.
Im sure it only took them 5 min to change. The light came back on the day after.
I hate the dealership.
Well now they are telling me its the fuel filler neck.
I would do the work on my car, but I have never worked on mercedes vehicles.
I dont want to mess something up and regret it. Its not a dodge or Chevy.
Well this sucks.... I dont know what to do?
Last edited by mblkout23; Feb 18, 2010 at 08:53 PM.
MBWorld Fanatic!
Joined: Nov 2001
Posts: 5,851
Likes: 196
From: Huntington Beach, Ca.
'17 Jaguar XF
It's not 'almost' or they would have repaired it properly.
Guess what, Mercedes is built with the same fasteners (for the most part) as all cars. If you search, start by really reading this whole post, you'll find....it's been covered several times and even with pictures.
Guess what, Mercedes is built with the same fasteners (for the most part) as all cars. If you search, start by really reading this whole post, you'll find....it's been covered several times and even with pictures.
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Senior Member
Joined: Sep 2008
Posts: 468
Likes: 23
From: Los Angeles
2005 C230 Sport Coupe
(I dont have a coupe.)
Can you remove the fuel filler neck on the sedan with the same procedure?
I fuc*en hate my check engine light.
I just wasted $350 dollars, so that the dealership can change my stupid purge valve.
Im sure it only took them 5 min to change. The light came back on the day after.
I hate the dealership.
Well now they are telling me its the fuel filler neck.
I would do the work on my car, but I have never worked on mercedes vehicles.
I dont want to mess something up and regret it. Its not a dodge or Chevy.
Well this sucks.... I dont know what to do?
Can you remove the fuel filler neck on the sedan with the same procedure?
I fuc*en hate my check engine light.
I just wasted $350 dollars, so that the dealership can change my stupid purge valve.
Im sure it only took them 5 min to change. The light came back on the day after.
I hate the dealership.
Well now they are telling me its the fuel filler neck.
I would do the work on my car, but I have never worked on mercedes vehicles.
I dont want to mess something up and regret it. Its not a dodge or Chevy.
Well this sucks.... I dont know what to do?
Dave
Newbie
Joined: Feb 2010
Posts: 3
Likes: 0
05 c230
MBWorld Fanatic!
Joined: Jul 2008
Posts: 8,384
Likes: 800
2019 G70 6MT & 2022 Ford Maverick XL
This doesn't surprise me. When my car threw this code at 35000ish miles, the dealership replaced the purge valve and a few other parts before replacing the fuel filler neck (which actually fixed it). Maybe you should demand a refund since the purge valve was not bad? I would.
Senior Member
Joined: May 2006
Posts: 314
Likes: 2
From: Pacific Northwest
"One Man. One Engine."
I've had a long story on my CEL problem (small evap leak), and this is what the dealer did...
replaced purge valve - 4X
replaced MOT valve
replaced fuel tank
replaced updated fuel sending units
replaced ECU or ME
replaced activated charcoal canister
and finally...
replaced fuel filler neck with expansion tank
Good thing, it was all done under warranty!!!!!
replaced purge valve - 4X
replaced MOT valve
replaced fuel tank
replaced updated fuel sending units
replaced ECU or ME
replaced activated charcoal canister
and finally...
replaced fuel filler neck with expansion tank
Good thing, it was all done under warranty!!!!!
Last edited by power-fade; Mar 2, 2010 at 11:21 PM.
Thread Starter
Member
Joined: Nov 2005
Posts: 121
Likes: 0
2007 cls63 AMG
For the guys who have had the filler tube leak, where exactly was it leaking? I am wondering if a gob of epoxy will do the trick, since it is just a small air leak. I still have this problem and have just learnt to ignore the check engine light!
Super Member
Joined: Mar 2007
Posts: 812
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From: centennial, CO
2003 c240
I recently installed a new fuel pump and am now getting a p0422 CEL. During siphoning I may have damaged my filler tube. Is there any good way to check this and is this repair DIYable?
Member
Joined: May 2011
Posts: 147
Likes: 0
05 C230K Sport
I have had this same problem for two months since I bought my car and the cel came on the next morning. needless to say I was a little upset. it is at the dealership right now, third time, first was smoke test to find out charcoal canister was bad, wait two weeks for part, second was replace charcoal canister, light came back on a day later, had to wait a week plus to get back in, another round of smoke test, just spoke with sa, replacing filler neck now. I hope this is the answer. I guess I know why the last guy traded it in. if I end up with anything else to try when they eventually get this fixed I'll post again.
