Hello, sorry if there is already a thread for this but not really sure what to look for/what my problem even is. So for a little context my car is a series 4 n/a engine was just rebuilt 4k miles ago and was running great ever since i finished the rebuild until it wasnt one day it started missing pretty badly at idle you can clearly hear it puffing out of the exhaust (thats with an exhaust leak) and i do smell fuel every once in a while usually at stop lights, along with atrocious gas milage, thought it was my o2 sensor because the one i had was completely broke so i replaced it and no help, still missing and now im starting to notice almost a power decrease, like the missing is getting worse before it was strictly at idle now its all rpm if i ease up in the rpms? and now the car take a while to start alot of cranks, when it never did before nor after the rebuild, also when it did start this morning after multiple cranks a cloud of fuel smoke puffed out the exhaust. my injectors have been cleaned in the last 5k miles fuel filter in the last 8k. and i was seeing people say that fuel pulsation dampers fail causing gas leak but looks like mines already been deleted with a bolt..? could be wrong tho its the inner fuel rail on the right side (from passenger side) theres no plastic just a bolt, could that be my issue possibly? anything helps thank you

 

welcome to the board.

how healthy is the battery (and cables) and/or alternator? if they check out fine, then check the compression.