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I'm with the OP on this one. Sorry guys. I would replace all ignition parts (except plugs) from Autohausaz. Leave the ignition wires alone. They only have 4 years and 40K on them. Way too soon if they were quality wires to begin with.
Unless they have cracks on them of course. Autohausaz does not have proper sparkplugs for the M103, so look elsewhere there.

It takes a lot to throw the engine check light on these cars. I mean a lot.
The engine could be barely starting with serious ignition issues and still, it will no trip the check engine light. That has been my experience.
Y'all have helped diagnose my issues in the last 2 years and with all the poking and the prodding, the check engine only came on once. Minor ignition problems do not seem to do it.

He's got some other major issue. It is sufficient to establish baseline on the ignition wear items using parts from reputable companies (Bosch, Beru, etc) even if one knows they may have to be replaced in 1-2 years.

I believe the OP will be spending some money and time elsewhere anyway.

- Cheers!
 

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I agree that the check engine light on these older cars are almost always exclusively related to emissions related issues i.e. oxygen sensor, EHA, etc, etc, etc.

BUT, the W124 is a biatch when it comes to being sensitive on ignition components. My general rule is, on the CIS-E motors always use original OE components for all distributor related components (cap, rotor, suppression disc, o ring, rotor driver).

Using anything else is a short term fix . . . at best and in the long run not economical.
 

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I agree that the check engine light on these older cars are almost always exclusively related to emissions related issues i.e. oxygen sensor, EHA, etc, etc, etc.

BUT, the W124 is a biatch when it comes to being sensitive on ignition components. My general rule is, on the CIS-E motors always use original OE components for all distributor related components (cap, rotor, suppression disc, o ring, rotor driver).

Using anything else is a short term fix . . . at best and in the long run not economical.


Without being on this forum, and not getting the warning, I have tried aftermarket parts on the M103 engine in my W201. It runs alright with them for me so far. (Not interested in shelling out big $$$ for it at this stage of my life, I’ll be quite honest that I just installed a less than $10 air fuel meter potentiometer), and after a little tinkering, the car is back to running without the Check Engine light lit).

Sorry, but not sure which engine you refer to, W124 is not an engine, and I barely know which engine is what....
 

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I purposely did not mention any specific engine because this issue (check engine light, worn air flow pot, leaking EHA) affects all MB engines with KE-Jetronic. (M102, M103, M104.980, M116, M117, etc, etc)
 

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Discussion Starter #25
If the O2 code keeps coming back even after replacing, did you check the wiring/for proper signal?
I haven't checked the signal but the wiring is solid. At first I thought mice might have chewed the wires but it looks to be intact from the sensor all the way to the firewall, where I'm assuming it's terminating at the MAS. But, I need to clear out the battery out of the compartment and really look closely to make sure no rodent damage in that area.

Rodent is a big issue where I live in the mountains unfortunately.

Thank you.
 

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Discussion Starter #26 (Edited)
I'd agree with that for the rotor arm. My original was 18 years old and working like a dream. Changed it for a Bremi that died in 18 months. Original is still in stock if ever the new MB part fails. Same goes for the cap - cleaned up with a Dremel and looks almost new.

My leads are Beru - no complaints.

Plugs from Beru/NGK, no complaints.

It sounds as if generic Bosch is no go for cap/rotor/rear shield.

Good luck.

RayH
The cap looks good w/o any carbon tracking. The usual wear/buildup on the terminals. The rotor is ground down as expected, not sure how much protrusion was there when new. I found a Beru rotor arm on ebay only so I'll order it.

Spark plug is NGK BP6EF with a gap of almost 0.060" and the internet says the gap needs to be at 0.28". Internet also says this plug has been replaced by BPR6EFS. Unfortunately NGK BPR6EFS is a resistor plug and my current set is not a resistor plug. I'll re-gap these and order another set from U.K. like last time.

Thanks for the heads up.
 

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Discussion Starter #27
If anyone has an AutohausAZ promo code, please share it!!!

Thanks.
 

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Spark plug is NGK BP6EF with a gap of almost 0.060" and the internet says the gap needs to be at 0.28". Internet also says this plug has been replaced by BPR6EFS. Unfortunately NGK BPR6EFS is a resistor plug and my current set is not a resistor plug. I'll re-gap these and order another set from U.K. like last time.
Not sure whether you have the M103 or M104 engine. These plugs appear to be the correct ones for my M104.980:

Bosch F8DC4
Beru 14F-8 DU4
Champion C11YCC
NGK BCP5ES >>> Or maybe BCP6ES. Anyone know the difference?

The first 3 are marked as such on a label in front of the engine so recommended by MB.

RayH
 

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For all twin cam motors in the W124 (M111, M104, M119, M120 (Brabus)) the Bosch F8DC4 is the one stop shop.

Re. BCP5ES vs. BCP6ES, the BCP5ES is one step hotter.

No idea why NGK goes backwards. Not logical in any way very unlike the Japanese, much more like the French and their Crit'Air emissions stickers (Buy a Euro 6 car, get a Crit'Air 1 sticker). Wonder what they'll do when the Euro 8 norm goes into effect? Perhaps hand out -1 stickers?
 

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Discussion Starter #30 (Edited)
I have the M103 engine and will check out the Bosch plug mentioned above. Hopefully it'll be a non resistor plug as well, does anyone know?

Thank you.

Sent from my SM-G960U using Tapatalk
 

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The Bosch F8DC4 is not physically suitable for the M103, only the twin cam motors

One is a tapered seat plug [ Conical seat ] and the other is a compression Ring gasket plug [ Flat seat]
 

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Use the suggested NGK plugs or Denso T20-EPU. NGK plugs can be had from clubplug.net and Denso's I've found from Amazon and eBay sellers.

Both brands meet factory specifications for non-resistor, copper core and beveled gasketless seat.

Jayare

Sent from my XT1710-02 using Tapatalk
 

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Discussion Starter #34
Excellent, thank you.

Sent from my SM-G960U using Tapatalk
 

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Discussion Starter #37
seems that everyone is out of Beru ignition rotor arm. I found on Ebay but the seller just told me that they're out of stock as well, even though their ebay ad is still showing Beru.

What's the next best thing I should be looking for?
 

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Discussion Starter #39
Use the suggested NGK plugs or Denso T20-EPU. NGK plugs can be had from clubplug.net and Denso's I've found from Amazon and eBay sellers.

Both brands meet factory specifications for non-resistor, copper core and beveled gasketless seat.

Jayare

Sent from my XT1710-02 using Tapatalk
Thank you, NGK plugs ordered from clubplug.net . Easy peasy.

Beru rotor coming from a different Ebay seller, hopefully they're not out of stock.
 

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Discussion Starter #40
Clubplug.net just emailed me to tell me that they no longer non Resistor plugs and cancelled my order. I was trying to order the NGK plugs but now I'll try Denso T20-EPU, assuming they're non Resistor as well.
 
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