Why runs rough when hot
Thread Starter
Junior Member
Joined: Sep 2020
Posts: 34
Likes: 0
From: Southern CA
500SL 450 SL 230 SL E320
Why runs rough when hot
Help!
My E320 wagon runs great when cold but runs rough and misses after 10 minutes when reaches full temperature.
What are possible casues ?
My E320 wagon runs great when cold but runs rough and misses after 10 minutes when reaches full temperature.
What are possible casues ?
Junior Member
Joined: Oct 2010
Posts: 44
Likes: 20
From: Jacksonville, FL
2016 AMG GTS
Possible fuel venting issue. When it is doing that, pull in to a gas station and slowly undo the gas cap and see if you have a lot of vacuum. Charcoal canisters can cause this.
Thread Starter
Junior Member
Joined: Sep 2020
Posts: 34
Likes: 0
From: Southern CA
500SL 450 SL 230 SL E320
Member
Joined: Mar 2008
Posts: 122
Likes: 29
From: Texas
S63 AMG Coupe AMG GT55
Wondering if it's a "simple" vacuum leak. The cold start circuit is dumping more gas to mask the lean effect of an open vacuum sucking more air. When it warms up and the system goes back to less fuel delivery, then you could be going into a lean mixture. Or, like all electrical, something is breaking down electrically as it heats up. Even a coil or plug wire can give this type of issue. (less likely) The Charcoal canister issue if the culprit, will give you a very strong smell of raw gas when parked and a rich mixture from the recovery system won't allow it to idle without hunting for a steady idle RPM.
It's always fun isn't it
This is still OBD I??
It's always fun isn't it
This is still OBD I??
