Perform OBII scan reveals 2 codes. P300 and p301. Never change spark pugs or wires please advise. Thanks much.

clean Maf sensor,if that does not make it smooth change plugs wire are good for 250,000 miles.my advice was for someone who can't read the codes

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

Both codes suggest a secondary ignition miss fire.
Spark plugs and or wires are the most likely cause.

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MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

You are ignoring the maintenance requirements of your car if you haven't changed your plugs in 110,000 miles.

Spark plugs are a few dollar a piece.

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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".

You may have broken vacuum lines too.

I had one similar code like yours, and I found the a rubber wye vacuum fitting just gooey and nearly melted(remember it is just rubber). This vacuum fitting is around the bottom front of the throttle body. I had about the same amount of miles when it happened to me.

Check for vacuum leaks.

When you remove the plastic cover to get to the plugs and coils. Two plastic vacuum lines run through there, and those control the EGR and electric air pump valve.

Martin

Isn't the spark plug change interval on that engine 30,000 miles? Exceeding the change interval by 400% might cause some running issues...

you can go 60,000 miles with Bosch Super plugs,100,000 with iridium plugs.
But plain copper gives the fastest 1/4 mile times.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

If I am not mistaken, P0300 is Random cylinder misfire. P0301 is Cylinder 1 misfire. P0300 can be caused by the P0301 so find out what is wrong with cyl #1 first. Probably a coil.

Paul

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84 500 SEL (307,xxx miles)

Thanks much everyone. Change plugs. Looks fine