M156 Rough Start on Cold Start, Smooths Out. No Misfire or Engine Mount
01-05-2022, 05:18 PM
#1
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M156 Rough Start on Cold Start, Smooths Out. No Misfire or Engine Mount
Starting up my new 130,000mi 63 engine (new spark plugs 2k miles, headbolts replaced) and I get a pretty rough start on cold start. It definitely feels like a misfire/rough run once revs drop, but then it smooths out quickly and I get nothing more of the sort.
No DTCs, no Fault Codes, no Events in DAS. I ran both cold start and smooth engine tests in DAS and the system detected no fault codes/misfires in the counter.
I tested the motor mounts looking for engine "winking" and nothing. Rock solid.
What should I try next?
No DTCs, no Fault Codes, no Events in DAS. I ran both cold start and smooth engine tests in DAS and the system detected no fault codes/misfires in the counter.
I tested the motor mounts looking for engine "winking" and nothing. Rock solid.
What should I try next?
01-05-2022, 06:57 PM
#2
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2007 Mercedes E63 AMG
you'll want to check your PCV as they fail anywhere between 50-80k. in addition to this, your throttle body mounting plate may be leaking as well as they do wear out.
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kpuri (11-21-2023)
11-25-2023, 07:40 PM
#3
sorry to revive an old thread, but what did this end up being? i see a little oil on the back of my intake manifold so it probably needs a new throttle plate but i’m experiencing the same issues.
