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Old 12-20-2003, 02:28 PM
suginami suginami is offline
Join Date: Dec 2001
Location: Southern California, U.S.A.
Posts: 8,508
[QUOTE]Originally posted by deanyel
Originally posted by suginami
The M104's haven't been around for that long. The
"modern" HFM-SFI M104 was first used in the U.S. on W124's in 1993. That's only 11 years.

I agree with the point but the first application was actually the 1992 140 body, which was slightly misbadged as a 300SE.
I didn't include the early 3.0 liter M104's on the 300CE's, and the 1992 300SE because they are not HFM-SFI. The early M104 used the old mechanical CIS-E fuel injection, and the 3.2 liter in the 1992 300SE was an LH system, used only for this one year.

I believe it makes a difference in the long term reliability of the engine.

The HFM-SFI fuel injection system (hot-film mass air flow sensor) is fully electronic, with integrated electronic ignition and sequential fuel injection. This system combines fuel injection and ignition control in one module.

HFM fuel injection systems are designed so that idle speed can't be adjusted. Idle speed is completely controlled electronically. This HFM injection system also has adaptive technology that compensates for conditions such as engine wear and unmeasured intake air and is designed to maintain driveability as the engine ages.

HFM-SFI can retard engine knocking to just the knocking cylinders, unlike EZL technology, which retards spark timing across the entire engine. This keeps the ignition timing point as advanced as possible for maximum power output.
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".
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