Merc V6 EFI backfire while starting up

[Ebola]

My engine backfires through the throttle body when I crank it up. Does anyone have any suggestions on what might be causing this? The motor has been sitting a while and I don't really know what shape the valve train is in. I will be pulling the motor for a rebuild and would like to have as much info going in as possible.

Thanks,

E

 

[farmer9009]

Re: Merc V6 EFI backfire while starting up

Timing being off is the first place I would look. Spark plugs wired correctly also.

 

[Bondo]

Re: Merc V6 EFI backfire while starting up

Ayuh,... Bad gas, it's Lean...

 

[Ebola]

Re: Merc V6 EFI backfire while starting up

Gas is new, it only backfires with one pop when turning over before starting, maybe twice. From what I've read, it's a timing issue or maybe a plug wire arcing. Just wanted to see if these motor had a tendency towards one or the other. thanks for the replies.