For over a year now I've had problems starting my 2001 volvo s40. I've had it checked out by 4 different mechanics who still haven't found out what the issue was. I even left the car in the garage for the whole weekend.

-The issue started last summer and started fine for a couple of months until winter. During the winter it takes a lot longer to crank but runs perfectly now since I just changed the coils. 95% of the time it takes about 3 seconds to start up and needs a few cranks.

-Things I've changed recently:
-Fuel filter
-Spark plugs
-Coils
-No sensor problems
-No fuel pressure problems
-No transmission/engine problems
-The starter is working fine to so I know it isn't that.

The problem starts only when the car is left idled for more than 30min. If I start the car and drive off then close it and turn on the car again it ALWAYS starts fine. So the issue is when the car is idled.
Thank you.

-I really need someone's help. The mechanics told me it could be the Fuel Pump BUT that's expensive to fix and I want to make 100% sure.
Additional Details

PS: There is also nothing wrong with the battery and I changed gas about 4 months ago. I only use Premium or V Power. The highest quality gas. The problem is not only in the winter it is all year around now.

 

THis post is a little difficult to understand, but have you checked the fuel pressure regulator on the rail? If you pull the yellow vacuum hose from the regulator going to the manifold and notice any fuel in this line, it needs to be replaced.

 

The fuel pressure was checked and there's nothing wrong with it. Basically the car has a 90% chance of starting with no cranking. This only happens when the car is idled for over 30min. The problem seems worse in different weather conditions such as during the winter or really rainy days. So it seems like the issue is when it's idled and NOT when the car is warmed up. I really thought it would be an ECT sensor issue but according to the mechanics there is no sensor issue.

Another thing is that I do occasionally smell gas when starting the car.

I also changed the timing belt at 150km it now has 180km

 

Mine was the fuel pressure regulator.

 

Yea supposedly my fuel pressure is fine...