The car has 113 000 miles on it. It has a Tiptronic
This problem started about 4 months ago. First of I don’t drive this car every day .
When the car is hot minimum 15- 20 min or longer driving, full operating temperature.
After I turn it off and right back on the car starts the normal. If it sits about 30mins to 1hr the car is very very hard to start. Actually it will start after trying for about 5 mins or so. It smells of gas and is flooding. It has not left me stranded. Here is the hard part about this problem it is intermittent most of the time it starts fine. It is ok for 1 week or so then I go somewhere and it happens again. The check engine light has never come on!
This is what I have done about it. First I replaced the spark plugs my existing ones had about 25 000 miles on them. The problem persisted. My mechanic told me that the ECU (engine control unit) on that type car often goes bad and showed me how to replace it. That seemed to help for a few weeks.
Then it started again. The mechanic could not recreate the problem. Every time I took the car into the shop it would start normal.
They checked and determent it could be the fuel pressure switch.
The theory was that the fuel is dripping slowly into the cylinders and causing it to flood while sitting for 1hr.
It was replaced the problem persisted. Next I had the Fuel injectors checked, cleaned and rebuilt. It seemed to help for about a week.
Now I’m back to the same problem. Sometime it starts sometime it does not.