1998 Mercedes Benz ML320 cyl 1 and sometimes #2 read miss f

1998 MERCEDES BENZ ML320
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RRAPP1957
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Engine Performance problem
1998 Mercedes Benz ML320 6 cyl All Wheel Drive Automatic 147k miles

intermittent missfire, car will run fine then hardly run past 40 mph. 147,000 miles, new plugs at 100k, changed fuel filter because fuel pressure read 35psi, now reads 45 psi.
Plug wires? MAF sensor? fuel pressure? not sure what to do.
Mar 4, 2009 at 6:06 PM
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MHPAUTOS
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HI there,

I would be checking for a vacuum leak around No 1 & No 2 cyl, start there.

Mark (mhpautos)
Mar 4, 2009 at 6:33 PM
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GFIMOTORCARS
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You may want to consider failed coil packs for these cylinders. If you are getting misfire codes I would hesitate to go after a maf sensor. Coil packs are easy to replace and may very well take care of your misfire.
Mar 8, 2009 at 12:47 PM
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