I have previously been critical of how much noisier HFM versions of the M104 I have driven were than the M103 in my '90 300TE. My M103 is quiet at all throttle openings and only becomes audible at very high engine speeds. My father has a '93 E320 coupe (W124) with the 3.2 M104. Even at small throttle openings it has what appears to be induction "growl". Under normal driving conditions this can be annoying. At wide throttle openings this becomes an enjoyable sound that matches the spirited performance (being an Aussie delivery it has the 5-speed auto and 3.69 diff). It is even possible to hear and feel the points where the inlet manifold resonance tuning and inlet cam timing changes. A '93 E280 sedan (W124) with the similar M104 that I once drove made similar noises.

On the weekend a friend asked me to test drive a '93 300TE 2.8 (aka 280TE) that he is considering purchasing. This car has the same 2.8 HFM M104 to the E280 and a very similar to that in the E320 yet sounded and felt almost the same as my '90 300TE. Absent was the growl of the other cars with the HFM M104. The switchover points in cam timing and manifold tuning were also not obvious.

What now puzzles me is what causes the noticeable difference. I had always assumed the extra noise of the HFM M104 to be due to the plastic inlet manifold and ducting and yet here is one that is almost as quiet as my M103. Is it due to the wagons having a very different rear muffler to that on the sedans and coupes (ie. exhaust noise rather than induction noise)? All cars in question have standard inlet and exhaust systems. All appear to be running well although the wagon I test drove on the weekend did have slightly hunting idle speed in neutral and the idle speed would drop low enough to become rough when slowing to a stop at which point it would then recover to the correct speed (what could be the cause of this?). Its performance was about on par with (although no better than) my 300TE which looking at the specs would seem about right (M103 = 135kW, 2.8 M104 = 145kW).

Can any owners or regular drivers of various W124s (M103 vs M104, sedan/coupe vs wagon) please describe their experiences of noise levels?

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107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.

I had a '93 300TE with the 104 3.2 litre 'on trial' for a bit and I too thought the engine was very noisy compared to my 103-powered 300E, almost to the point of it being annoying. Went like stink though

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1993 320TE M104
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past:

1983 230E W123 M102
1994 E300D S124 OM606 (x2)
1967 250SE W108 M129
1972 280se 3.5 W108 M116
1980 280SE W116 M110
1980 350SE W116 M116
1992 300E W124 M103
1994 E280 W124 M104
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"music and women I cannot but give way to, whatever my business" -Pepys

Any others with driving experiences of various W124s, especially the M103 versus the M104? I have been wondering what the effect on the M104 would be if the variable inlet cam timing and inlet manifold resonance switchover was not working. In hindsight, I feel the 300TE-2.8 I drove should have performed a little better than it did. I am puzzled by the lack of induction noise on this one compared to other HFM M104s I have driven. This one was almost as quiet as my M103 300TE. Then there was the tendency for it to almost stall when slowing to a stop and the hunting idle in neutral. Any ideas or comments? I would interested to know as the car presented very well otherwise and my friend is seriously considering it.

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107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.

I have a '93 300E 3.2, have driven a '96 W210 E320, and have driven many 300E's.

My engine is whisper quiet. There is no induction noise to speak of. Just a beautifully sounding, swiss-watch-like mechanical, precision sound when I wind the car up to the red-line. My motor mounts were replaced 3-4 years ago, and my idle is ultra-smooth. There is barely a hint that the car is even idleing.

My experience in the W210 was that the engine note was even quieter.

The M103 300E's I have driven have been good and bad. I have been in a later model 300E, a 1991 300E, and the engine was quiet and smooth, with a gradual power delivery, lacking the kick that the M104 has at the top end.

I have driven an early model 1988 300E, and the idle was lopey, like it had a hot cam. I was told by the owner, Larry Bible, that the early M103's had hotter cams.

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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".

Paul,

It surprises me that MB would manufacture a car with more noise than the version before it. It is for this reason that the noise level of the HFM versions of the M104 powered W124s that I have driven surprises me when comparing them to those with the M103. Having now driven one that was relatively quiet proves that they are not all noisy. The puzzling issue is why the difference. Maybe the noisy ones do have some problem, although strangely it was the quiet one that did not seem to be running perfectly. The best performer of all that I have driven also happens to also be the noisiest, my father's '93 E320 coupe. This thing really performs although I suspect much of it is due to the 5-speed auto with the surprisingly short 3.69 diff. Around town the "drone" it produces, especially at low revs, is annoying. On a twisty country road the noise becomes a glorious induction growl, especially when it really comes alive above 3500 RPM. Mechanical noise and noise levels at idle or on a trailing throttle are not a problem. It is only with the throttle open, even only slightly that the noise is apparent.

Greg

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107.023: 350SLC, 3-speed auto, icon gold, parchment MBtex (sold 2012 after 29 years ownership).
107.026: 500SLC, 4-speed auto, thistle green, green velour.
124.090: 300TE, 4-speed auto, arctic white, cream-beige MBtex.
201.028: 190E 2.3 Sportline, 5-speed manual, arctic white, blue leather.
201.028: 190E 2.3, 4-speed auto, blue-black, grey MBtex.
201.034: 190E 2.3-16, 5-speed manual, blue-black, black leather.

The M104 motor is wonderful!

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2006 E350 w/ 155k miles (Daily Driver)

Previous:
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)

I think there is more induction noise on the M104 engine, because it is a Dual-OverHead Cam with twice as many valves as the M103 engine.

In short, it breathes more, hence more induction noise.

If you think the M104 in 2.8L or 3.0L HFM sounds aggressive, you should try the AMG C36 M104 engine (3.6L).

I have the AMG C36 powertrain in my W124 wagon, and it has LOTS of induction noise, but it is VERY quick (3.07 diff).

:-) neil

Hmm.

I would look for things like missing gaskets on the air filter housing, broken "snorkel", and so forth, along with squashed engine mounts.

MB does NOT make loud engines, hasn't since the early 60's when engine/road noise were identifed as major causes of driver fatigue and distraction. "Induction" noise is likely a leak or something loose, and any MB engine mounted on gel filled mounts (basically anything after 1985 except the W126) will be MUCH louder with bad mounts. They get amazingly quiet again when the mounts are replaced.

Something else to look for is a minor exhaust leak, dead mufflers, bad tranny mount (good for excessive vibration on acceleration) and bad flex disks or center bearing carrier.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Based on my limited experience with MB's so far, I would venture to say that some of the 104's had cast iron exhaust manifolds with insulating shrouds and others have unshrouded stamped stainless manifolds. The cast iron manifold will always be quieter than the stamped steel versions. Just my $0.02 worth.

I have (3) M104 engined cars:

1988 360TE AMG (1995 C36 M104)
1995 E320 wagon (W124 M104 HFM)
1995 E320 wagon (W124 M104 HFM)

The C36 M104 with it's aggressive cams sounds like a diesel at idle . . .

The exhaust manifolds for the 1995 C36 M104 and 1995 W124 E320's all look like cast iron with a stainless-steel insulating shroud.

Agreed. I just fixed an exhaust leak on my 300E that has been there since I bought the car. I have done engine mounts and all the usual stuff. There is no audible engine noise, no exhaust noise below 3000rpm. Even with all the windows down. Quite amazing.

I always personally thought the M104 was quieter at WOT compared to the M103. Ever revved out an M103 with walls/tunnel on each side to reverberate? Its an un-describable screaming. The M104 is just more refined of an engine comparatively IMO.

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http://i193.photobucket.com/albums/z...-RESIZED-1.jpg
1991 300E - 212K and rising fast...