1999 W208 error P0450 fuel smell
10-30-2015, 08:08 PM
#1
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1999 W208 CLK430
1999 W208 error P0450 fuel smell
Hi there, I have an immaculate W208 that has now only 25,000Kms.
No issues so far, drives and smells like new but I can't fill it up otherwise the gas leaks under the car.
CEL with P0450, isn't the fuel cap.
Any suggestions?, isn't really bothering me but the smell of gas sometimes is strong.
No issues so far, drives and smells like new but I can't fill it up otherwise the gas leaks under the car.
CEL with P0450, isn't the fuel cap.
Any suggestions?, isn't really bothering me but the smell of gas sometimes is strong.
11-01-2015, 11:07 PM
#2
MBWorld Fanatic!
The short story is, it sounds like your tank isn’t venting and there's a vacuum leak - possibly a cracked / rusted out charcoal canister or line to/from it. If you're not handy, just take it to a dealer.
If you are handy, and you want the technical answer - the W208 has a saddleback gas tank with two vent lines (which makes sense for a saddleback tank). As you fill the car with gas, vapors go from the gas tank, through a vent line, to the expansion reservoir. The fumes then go across another line from the expansion reservoir to the charcoal canister. The fumes then go from the charcoal canister to the purge control valve, which at times, receives a vacuum from the engine. That vacuum clears the fumes. When someone can't fill their W208 with gas, commonly the canister is clogged.
Why is the canister clogged? If gasoline gets into the canister, say by someone overfilling the gas tank, the charcoal will break down, clog the system, and very little, if any, air will be able to pass through. If air can’t leave the gas tank, fuel won’t go in. The canister will also clog due to old age because gas fumes will break down charcoal too.
There are several options; replace the canister with a new one, make a new canister (all one needs is charcoal and a sealed container), or spend $15 or so to do a workaraound. Don’t go cheap and just unplug the vent lines. Yes, that will allow you to fill the tank, but OBDII will toss a code.
Where is the canister? Remove the driver’s side rear wheel, then remove the plastic inner cover, and look up. That’s the charcoal canister.
If you are handy, and you want the technical answer - the W208 has a saddleback gas tank with two vent lines (which makes sense for a saddleback tank). As you fill the car with gas, vapors go from the gas tank, through a vent line, to the expansion reservoir. The fumes then go across another line from the expansion reservoir to the charcoal canister. The fumes then go from the charcoal canister to the purge control valve, which at times, receives a vacuum from the engine. That vacuum clears the fumes. When someone can't fill their W208 with gas, commonly the canister is clogged.
Why is the canister clogged? If gasoline gets into the canister, say by someone overfilling the gas tank, the charcoal will break down, clog the system, and very little, if any, air will be able to pass through. If air can’t leave the gas tank, fuel won’t go in. The canister will also clog due to old age because gas fumes will break down charcoal too.
There are several options; replace the canister with a new one, make a new canister (all one needs is charcoal and a sealed container), or spend $15 or so to do a workaraound. Don’t go cheap and just unplug the vent lines. Yes, that will allow you to fill the tank, but OBDII will toss a code.
Where is the canister? Remove the driver’s side rear wheel, then remove the plastic inner cover, and look up. That’s the charcoal canister.
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Mt. T (10-11-2021)
12-24-2015, 04:59 AM
#5
Super Member
Canister location did not change for the W208, leak location is underneath the car by gas tank (wheel arch).
