Time to replace the injector on Sport 300 #25 - recommendations?

[jollyroger]

Everyone, as the title already states, it is possibly time to replace the stock injectors on my S300.

Some stuttering/misfire happens occasionally under heavy load (and under regular driving too, but more sparingly), and after checking coils, sparks, etc. my attention is going towards the fuel system.

Filter is new, so I suspect injectors/pump, anything else I should look at?

I know this topic has been beaten to death, but I am seeking some words of wisdom before I go ahead.

If it's indeed time to let the old injectors go, are there any options out there that are proven to work very well, keeping the original ECU in place?

Thanks in advance...

[Rambo]

You say you've checked the coils and plugs, but have you also checked the ignition leads?

Same symptoms happened to me recently (M100) so I changed the plugs as a matter of course then the ignitiin leads and the problem disappeared. My original leads were >30 years old.

[jonwat]

8 hours ago, jollyroger said:

Some stuttering/misfire happens occasionally under heavy load

Missing under load is normally caused by a breakdown in the high tension ignition system when it's harder for the spark to jump the plug gap because of the increased compression & it leaks to earth so I'd tend to agree with Rambo.

[jollyroger]

Thanks everyone, the leads were also checked and we couldn’t find any apparent anomaly…

The misfire sometimes happens while not under load.

Edited October 26, 2023 by jollyroger

[sailorbob]

Have you tried datalogging using Espritmon or TunerPro to see if that gives a clue as to what may be happening?