Advice needed: First start after Harness, ETA, and Ignition overhaul (Austrian 500E)

[dinbirb]

Hi everyone,


I’m writing to you from Austria. I’ve been working on my father’s 500E, which unfortunately fell victim to two incompetent shops before I took over. I would love to get your expertise before I try to fire it up again.


The Backstory:


The car was originally caught by the police for running without a catalytic converter. A shop then installed a cheap aftermarket cat, which obviously didn't fix the emissions. In their "troubleshooting" process, they replaced several ignition components but managed to crumble the original (already fragile) wiring harness in the process.


To make matters worse, the car started misfiring and running poorly after their "repairs." When I inspected their work, I found a crack in one of the new distributor caps. I also discovered they had only replaced 7 out of 8 spark plugs (7 Beru, 1 original Mercedes plug remained).


What I have done so far:


I decided to do it right and have performed the following:


• Installed an original Mercedes-Benz catalytic converter.


• Installed a brand-new engine wiring harness (upper).


• Had the Throttle Body (ETA) professionally rebuilt.


• Replaced all damaged ignition components with quality parts.


My questions for the experts:


1. Startup Procedure: Is there anything specific I should do before the first start? Should I perform a specific sequence for the rebuilt ETA to "relearn" its stops?


2. ECU Health: How can I verify if the control units (LH/EZL/ASR) suffered any damage from the short circuits caused by the old crumbled harness?


3. Adaptation Values: The battery has been disconnected for about a month. Does this effectively reset the adaptation/learning values on these LH-SFI systems, or is a tool like a "blink code reader" or Star Diagnosis required?


I really want to get this car back on the road in the condition it deserves. Any advice is greatly appreciated!


Thank you!

 

[gsxr]

Sounds like you have made good progress, fixing things properly!

1) Nothing is needed for startup. The new / rebuilt ETA will automatically synch with the E-GAS module if you leave the key on for at least 60 seconds while the ETA goes through its startup dance (clicks, pops, weird noises). No learning process occurs for fuel (LH) or ignition (EZL).

2) ECU - the LH module and EZL are generally unaffected by wire harness issues. Main thing is to check the LH module capacitor health. First check before starting is to cycle the ignition on/off. The fuel pumps should run for 2 seconds every time you cycle the key. If the pumps do not run at all, or only run the first time you cycle the key, the capacitors are bad. The second check is with the engine running, at idle, make sure the fuel pump relay below the rear seat is not clicking rapidly. If it clicks with the engine idling, the capacitors need replacement. This typically affects early LH modules with WOT enrichment, not later modules.

3) Don't worry about adaptation values. These are typically not reset when the battery is disconnected. Even if they were, the LH will automatically adapt as the car is driven. Adaptation can be reset to mean values either with a blink code reader or with digital scanner like Star Diagnosis (SDS with HHT-Win).

Good luck, and welcome to the forum!

 

[TerryA]

@dinbirb,
@gsxr has covered what’s really important but if the car has not run for a long time, before actually starting it I would turn the motor over until you get the oil pressure up to be sure it’s fully lubricated.