W124 ignition replacement?

[tintinmt]

Is it possible/viable to replace the original ignition system with a modern 'breaker-less' one on my 300-24v? I have read a few posts on here over the years about it being a weak area on the cars (124) generally, with it being recommended to replace the distributor cap etc on a more than normal basis.
If the answer is 'yes' please elaborate on a source of parts or someone to do the job.
Thanks.

 

[grober]

A well setup EZL system with all new components distributor cap/leads/rotor arm/coil should easily give you the performance you need. The standard MB system is "breakerless" anyway. A good tip is to renew the heatsink compound between the EZL UNIT and the wing as it dries out with age. High Thermal Conductivity Heatsink Compound : PCB Compounds : Maplin Electronics
Most aftermarket injection and ignition setups are looking at maxing power output at high rpms rather than street drivability. AND THEY ARE EXPENSIVE!= more than refurbing your existing setup
Here is a good site for mods. Performance Paddock - PeachParts Mercedes ShopForum

 

[RBYCC]

+1^

The EZL works quite well.
I've only replaced three distributor caps in 25 years....

What problems are you having with your ignition ?

 

[tintinmt]

Hi, The main issue (minor really) is that it holds back a little when accelerating sometimes and runs a little roughly sometimes when idling. I left the car for a few days in the week and when I drove it yesterday the symptoms were worse for a while as if it was damp somewhere.

 

[RBYCC]

Hi, The main issue (minor really) is that it holds back a little when accelerating sometimes and runs a little roughly sometimes when idling. I left the car for a few days in the week and when I drove it yesterday the symptoms were worse for a while as if it was damp somewhere.

Not sure what you have done so far.
Assuming the EZL ( ignition module ) is functioning within specification then always best to get the full system to factory specifications as Graeme previously replied..

First pull your spark plugs and "read" them.
They will indicate the condition of each cylinder and can give direction to most problems you are realizing.

You can test your coil for resistance and output.
Coils usually outlast the other ignition components.

New distributor cap, rotor, OEM style spark plug leads, and spark plugs.
Engine requires a non resistor plug as the leads have resistance built in.

Keep in mind that the fuel system is by a separate controller.

Ed A.

 

[Favour1]

Hello

I am a newbie here
Does anyone know of a very good independent Mercedes mechanic in the Dartford Area
I reckon the alternator in my M Class 2003 is playing up
Battery is not charging when engine is running

 

[tintinmt]

Earlier in the year the car had new - Coil, Rotor arm, Distributor cap, plugs & Ignition leads to cure what I understood to be a failed coil. The pre-existing symptoms described were all unaffected by the replacement of these parts. The independent specialist has been unable to diagnose the fault. To be honest, I live with the issue but I did wonder if 'modernising' the system was possible or practical.

 

[RBYCC]

Earlier in the year the car had new - Coil, Rotor arm, Distributor cap, plugs & Ignition leads to cure what I understood to be a failed coil. The pre-existing symptoms described were all unaffected by the replacement of these parts. The independent specialist has been unable to diagnose the fault. To be honest, I live with the issue but I did wonder if 'modernising' the system was possible or practical.

Pull the spark plugs out and see what brand and part number they are.
There should be no "R" ( resistor ) in the part number.
The ignition is very sensitive to resistor plugs and the more modern non copper core electrodes.

The plugs will tell the story of each cylinder, whether it is rich or lean or if there is a miss.

If the ignition system proves to spec, then you need to go on to the CIS-E fuel system settings.

Your specialist doesn't appear to be very special if he can't diagnose the problems.
These cars are pre OBD so a knowledge of both the fuel and ignition systems are imperative.

Vacuum leaks also are quite common as the vacuum tubing becomes brittle with age.
A leak can cause similar problems that you described.
Did the specialist check the vacuum lines in the engine bay ?

Only way the system can be modified is by changing the fuel injection to an EIF system and the ignition to fully computer controlled.
Expensive and still need someone knowledgeable to program the new system.

The factory EZL and CIS-E are just fine, but you need someone who is familiar with the settings and adjustments to work on the car.

 

[tintinmt]

Thanks RBYCC. Your answers are definitely stopping me from looking at the replacement route! The bottom line looks as though I should be taking the car to another specialist and letting them have a go at diagnosis; although to be fair, the current guys that I use may be taking a practical approach in the sense that they may be advising that it's not bad enough to warrant the time and expense yet.

 

[RBYCC]

Thanks RBYCC. Your answers are definitely stopping me from looking at the replacement route! The bottom line looks as though I should be taking the car to another specialist and letting them have a go at diagnosis; although to be fair, the current guys that I use may be taking a practical approach in the sense that they may be advising that it's not bad enough to warrant the time and expense yet.

Plugs are most important as the non resistors are at times difficult to source.
Modern resistor plugs with exotic metal electrodes tend to wear in the M103 and early M104 and will develop poor running.

A well tuned engine as yours will be very smooth and delivery seamless power through the RPM range.

Ed A.