intermitten light tapping noise
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98 e320
intermitten light tapping noise
98 E320, 38K miles
Hi,
I'm noticing an intermittent light tapping nosie from a part underneath the hood. There are tubes attached to this part, and at the end of the tube I have noticed very light saturation. I have attached a photo of the part, if someone could identify this part, it would be greatly appreciated. Thank you.
usaims
Hi,
I'm noticing an intermittent light tapping nosie from a part underneath the hood. There are tubes attached to this part, and at the end of the tube I have noticed very light saturation. I have attached a photo of the part, if someone could identify this part, it would be greatly appreciated. Thank you.
usaims
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
Labeled
MOT.........That is your purge valve.Intricate part of your smog system.
It turns on and pumps away fuel fumes that collect in the evap canister and the fuel lines and fume space in the fuel tank.Always at cold start and then as needed to clear fumes or certain times to test the obd2 smog checks.
Look on www.benzworld.org w210 diy section for my diy on annual maintenance cleaning.
Tap,tap,tap means it is doing the job intended
It turns on and pumps away fuel fumes that collect in the evap canister and the fuel lines and fume space in the fuel tank.Always at cold start and then as needed to clear fumes or certain times to test the obd2 smog checks.
Look on www.benzworld.org w210 diy section for my diy on annual maintenance cleaning.
Tap,tap,tap means it is doing the job intended
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98 e320
Ohlord, thanks for the technical explaination, I'm learning alot here. I just wanted to make sure it's not an issue. I just bought this car so I'm getting aclimated to the different sounds this car produces.
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
Preemptive
strike then.When you start the engine after overnight you will hear a roar from the front of the engine and increased idle speed.That sound is the secondary air injection pump,pumps air into the exhaust to bring the cats to temp in under 2 minutes.That electric motor sound is normal also
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98 e320
OhLord, thank again. Your explaination brought out an interesting point if it's related to the catillac converter. I posted on another thread about a subtle machine gun sound I'm getting underneath the engine, as the car gets hotter, performance degrades about 15%. Secondly, I put the palm of my hand over the tail pipe and the air blowing out of the tail pipe seems to be weak. That purge valve was't that loud when I first bought the car; sometimes, I can hear it from the inside of the car. And I see some saturation on the connections of the purge valve. By the way, the engine light did not go on. Do you think it's related to the cat converter?
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300E a couple 1994 w124wagon E320 Wagon/,1971MGB Track/Rally, MG Midget Autocross ,2000 E320 wagon.
Purge valve
is on the beginning part of the emissions cycle.Cats are on the other.Your tubes on the purge valve can be made more secure with a few small radiator clamps after cleaning or check that they are not cracked and need to be removed and replaced
The other sound(bad cats rattle like a can of pebbles) sounds like a leak in you exhaust system.Car gets warmed up metal expands and makes the leak worse.
Get it on a lift at an exhaust shop or an indie shop or up on a set of ramps(chock the rear wheels) and inspect it.
The other sound(bad cats rattle like a can of pebbles) sounds like a leak in you exhaust system.Car gets warmed up metal expands and makes the leak worse.
Get it on a lift at an exhaust shop or an indie shop or up on a set of ramps(chock the rear wheels) and inspect it.
