Description

Mercedes-benz 508 2001 Technical Manual

You have a Mercedes-benz 508 with a stumble at idle or a no-start condition. You pull a generic aftermarket wiring diagram and find three different pinouts for the same coil. That burns billable hours and risks damaging a $400 ME-SFI module. This 27-page Mercedes-benz 508 2001 Technical Manual is the original factory training material from Mercedes-Benz USA, Part 9 of the Ignition and Fuel Supply series. It gives you the actual coil control logic, ignition angle adaptation tables, and misfire detection routines that the engineering team wrote. No room for interpretation.

Fuel Supply & ME-SFI Engine Management – What the TOC Shows

Section one kicks off with the fuel supply and ME-SFI engine management system. The manual walks through the coil control circuit – power supply is fused, ground side controlled by the ME control module (page 3). You get the exact component locations and pin numbers for the 12 coils (T1/1 to T1/12). That alone will save you from chasing phantom shorts. The Fuel system flow and injector timing are spelled out in the factory sequence, not some reworked third-party summary.

Ignition Control: How the ME Module Sets Timing

The ME control module determines ignition angle based on five sensor inputs: hot film mass air flow, crankshaft position, camshaft position, coolant temperature, and intake air temperature (page 4). Each sensor is listed with its role. The manual then explains ignition angle adaptation in three sub-routines: catalytic converter heating (retards timing for ~20 seconds in Park or Neutral), idle speed control (retards up to 36 degrees, advances up to 20 degrees), and inertia fuel shutoff during deceleration. These are the exact parameters the factory uses to pass emissions and protect the catalytic converter.

Irregular Engine Running Analysis and Misfire Detection

Misfiring is detected by flywheel adaptation – the module monitors crankshaft acceleration variations. The manual shows the misfire screen data and how to interpret it. On page 5 you see the ignition angle adaptation table for decel shutoff, where timing is briefly retarded when fuel recommences. That’s a common source of post-fuel-cut jerks that aftermarket manuals blame on the throttle body. Here you get the real cause and the fix.

Knock Sensor and Timing Control

Knock sensor (KS) operation is covered in its own subsection. The manual explains how the ME module retards timing per cylinder when knock is detected, then recovers advance. It lists the acronyms used in the system – important when you’re cross-referencing wiring diagrams or reading diagnostic trouble codes. The 111 coil and dual spark plug system advantages are also detailed, including a coil installation note that warns about using correct dielectric grease and torque on the mounting bolts.

Technical Specs: 27 Pages of Factory Data

This is a PDF, 27 pages, published in 2001 by Mercedes-Benz USA, LLC. It is printed in the U.S.A. and carries a copyright notice that prohibits reproduction without written authorization. That means you are getting the exact training material used by Mercedes technicians. Each page is scanned from the original binder – not a reprint or a third-party copy. The document includes the official disclaimer that always refer to the latest Mercedes-Benz Technical Publication and WIS when performing repairs. Treat it as the baseline for any 508 fuel or ignition work.

Who Needs This Manual

Home garage enthusiasts who own a 508 truck and want to diagnose a misfire without swapping parts blind. Professional mechanics who need the factory coil control logic to scope a waveform. Anyone who has been burned by a aftermarket manual that says “install coil” and omits the ignition angle adaptation procedure. This manual assumes you know how to use a multimeter and a scan tool – it does not hold your hand, but it gives you the exact data the manufacturer intended.

Source Validity: OEM vs Aftermarket Documentation

I have seen aftermarket manuals that list the torque for the coil mounting bolts as 8 Nm. Wrong. The factory spec is different, and you will find it in this document. Aftermarket wiring diagrams often combine model years and leave you chasing a short that isn’t there. This manual is the original OEM training material, not a compilation. If you rely on third-party sources, you are taking a gamble with time and component cost. This 27-page factory manual eliminates that gamble.

Related Manuals

• Mercedes-Benz 508 Traction Control ESP Technical Manual
• Mercedes-Benz 508 Traction Control ABS Service Manual
• Mercedes-Benz 508 ETS-ASR Technical Manual

For related transmission diagnostics, refer to the Manual Transmission section in the workshop documentation. Also consult the Manual Transmission chapter for clutch and gearbox specs.

Frequently Asked Questions

Does this manual cover the entire engine management system for the 508?

No, it covers fuel supply and ignition (Part 9) only. For other systems like ETS, ASR, or ABS, use the related manuals linked above.

Are wiring diagrams included?

Yes, the manual includes coil control circuit diagrams and sensor input layouts. However, it does not contain full vehicle wiring harness schematics. The diagrams are training-level, intended to show system operation.

How do I use this manual to diagnose a misfire on my 508?

Start with the irregular engine running analysis section. Connect a scan tool and look at the misfire screen data. Check flywheel adaptation values. Then verify the ignition angle adaptation per the tables on page 5. If the angle is not within the specified range (e.g., retarded more than 36 degrees at idle), inspect the coolant temperature sensor and intake air temperature sensor inputs. The manual explains each correction factor. Do not replace coils until you’ve confirmed the ground side control from the ME module – the manual shows how to measure that with a scope.

Is this manual suitable for a beginner DIY mechanic?

If you can read a wiring diagram and use a multimeter, yes. It is technical but clearly written. Beginners will need to look up acronyms in the back. The manual does not teach basic safety or tool use.

Access the Factory Manual and get the OEM data that Mercedes-Benz intended for its technicians. That is the only way to be sure your 508’s fuel and ignition system is diagnosed correctly.