My Monte Carlo starts fine when it's hot out in Summer, Now that the temperature has changed a little It will do a small backfire when crank it, on a cold start.
If I cycle the fuel pump 3 times it starts with out a back fire ??
Any ideas, or something to test, I wad think maybe get a fuel pressure gauge to see what the pressure is ??
Thanks David

 

Id check your fuel pressure regulator for leaking fuel first. That's a fairly common failure, but there are others - leaky injector, etc. Checking fuel pressure is a good idea also.

Personally Id park it and work diagnosis ASAP. Not at all uncommon for 3800s to literally blow the intake manifold to bits with this kind of thing. I know you said small backfire, but it doesnt take a whole lot more fuel outside of the combustion chamber to make a small backfire into a big one.

 

about 5 years ago it back fired and blew the plenum apart, I replaced everything.
Was fine till a year or more ago.
Only happens when it gets colder and only on 1st start..
I'll check the for and try and put a gauge on it. I have a old brick scanner and a obd 2, but have had much luck finding any info with them.
​​Thanks !!!