Yesterday I changed wires and coils...last night i started noticing a stumble at Idle (and only at idle).. engine appeared to miss randomly and slightly but no pattern...also, cluster lights were flickering.....

Pulled the codes,,,all came back fine except for code 9 on pin 8 HFM .....something about high voltage?

What should I look for?

Since last week, I have changed wires, 2 out of three coils, voltage regulator, and OVP......I had the battery and alternator tested today at autozone..everything seemed fine........I don't want to go back and replace everything with the old parts unless i have to.....

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1993 300E, 2.8 M104 .....

OK,

So i put back the old coils, and found for some reason a loose coil-plug connector..? one of the new ones seems to be looser for some reason....the major misfire seems to have gone away, but it is still rough at idle with noticeable vibration in the cabin, also, cluster lights are still flickering?

Ideas?

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1993 300E, 2.8 M104 .....

bump for an answer code 9?

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1993 300E, 2.8 M104 .....

OK,

so now i put everything back where it should be, all the old wires, coils, connectors even the old OVP....

I have a noticeable roughness at idle, little bit of a light flicker, codes 9 & 4 on pin 8

attempting to reinstall the old voltage regulator also to eliminate possibilities......

any ideas? where are the experts?

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1993 300E, 2.8 M104 .....