Weird question I know.
For a long while my Mk1 Golf had trouble cold-starting. It would cough a few times but not catch until maybe the 6th attempt.
Over the years I tried a number of thing to try and fix it, including but not limited to:
- Adjusting timing
- Checking for vacuum leaks
- Replacing fuel pumps and filters
- Replacing injector seals
- Replacing IAC valve
- Adjusting idle screws.
None of these seemed to make a difference.
However, recently I filled the tank and noticed a bit of fuel was coming out of the top of the tank where the fuel sender unit is. The O ring seal there has always been a pain to seat properly so this time I used aviation gasket sealant as well.
And now not only is there no fuel leak but the car starts perfectly every time. Further more it seems the car is a bit more peppy than before.
I'm greatful this has made a difference, but I'm just not sure why it's made a difference. I mean, surely the fuel tank is not fully sealed otherwise air could not come in to replace the fuel that's being sucked out. Could anyone share some light on this?