What should vacuum read at idle M137 V12?
Thread Starter
Newbie
Joined: Oct 2018
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2001 S600
It's idling at around 670 RPM. Issues are down on power, occasional misfires, and smoke from the tailpipe after 15 minutes or so (and lots of it under load... no smoke until it's warm). The PCV system was clogged, so i cleaned the passage in the cylinder head cover and ran all new breather hoses. Greatly improved things, but it's still not running right.
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Joined: May 2015
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From: Miami, FL
2003 CL 600
Sounds mechanical, have you done a compression test? How do the plugs look, any saturated with oil? I'm not familiar with the M137 though so I'm afraid I won't be much help.
Thread Starter
Newbie
Joined: Oct 2018
Posts: 11
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2001 S600
New plugs, coil packs seem good (thus only misfires sometimes, not consistently), new plug insulators, checked for head gasket leak with bubble gas test from radiator, new intake manifold gasket. Have not done a compression test, but not getting inconsistent or unusual puffing when i remove the oil filler cap.
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From: Montreal, Quebec
2009 E350 4M Avantgarde;mistress 2002 S600; wife 2014 C300 4M
