Rough cold start but normal after like 3 minutes ? HELP!
 

I have an rx8 with about 190k km on it.
Had the coils and plugs swapped out 2 months ago.
Chained the tranny and diff fluid and got an oil change last week.
I have a brand new n3z1 starter as well
Also a Bhr midpipe and greddy sp1 exhaust
Everytime I come back to my car it starts really rough. Sputtering smoke and dropping revs. If I'm not in the car gently pumping my gas pedal it would stall almost immediately.
But as soon as I pump it a couple of times it maintains the normal revs and drives completely normal.
I have no problems with hot starts. Just when it's left overnight or for a work shift.

I have no idea what could be the cause if it. I've been reading that it could be a possible fuel pump or battery issue

Can someone help me out please ?

I'd start being concerned about a coolant or fuel leak into the housing, which is trying to stall out the engine until it's cleared up enough to run normally. Pressure test the coolant system, test the oil for coolant, test the coolant for combustion gasses, and/or let it sit overnight then briefly crank with the gas pedal to the floor (to cut fuel) then pull the plugs and see if they have gas or coolant on them.

I'm starting to smell a small amount of gas though my vents.
Could this signify a gas leak ?

The type of leaking i was referring to would be a leaky fuel injector. Nothing that would come through your vents. If you smell gas in the cabin, then you might want to pull up the rear seat bottom behind the driver's seat, open the fuel pump access panel, and check that for leaks.

If you have a leak there, it could cause problems at start too, from the fuel pump having a hard time building fuel pressure. That typically will make you lean at start, which usually wouldn't generate any smoke from the tail pipes. Though that might just be normal cold condensation.

Thank you so much for your help.
Would any of these be significantly expensive fixes ?

Fuel pump or injectors, no. Coolant leak into housing, yes (new engine)

Posted From RX8Club.com Android App

my girls 8 was having the same issues, when it was first cranked it ran rough then cleared out and ran fine. well it finally died, did not want to start anymore.