I have a 2000 Acura 3.2 TL that I bought from a dealership in May 04. The car hasn't given me any issues until now. When I start it first thing in the morning its fine, but I notice that when I am driving around and park the car for like 10 minutes or more while I run into the store or something, I come back, put the key in and start it up, it rumbles/shakes a little and then sometimes cuts off. Now, it doesn't do this every time I park it, only sometimes, mostly when I park it and it sits for just a little bit. When I go to work for 8 hours and I come back and start it, it's normal.

Also after it cuts off, I will start it again and start driving it and the rumbling goes away and the car starts driving like normal.

I told the guy at the Acura dealer this same scenario and he mentioned something about a "hot soak". Not sure what that means but I really just want to know what the problem is so I know what the damage will be to fix it.

Could be a number of things. The octane level of the gas may be too low. Or dirty fuel injectors that just spit fuel at first, or the engine brace is loose. I know I had a 4 cylinder front wheel drive that had a loose engine brace and all it did was bump around at first.

Heat soak refers to heat flowing to something that was not heated up when the engine was running. Modern engines have several temperature sensors. Following the ''heat soak'', one of them may be giving too high of a reading. Once the fluids start flowing, the heat sensors again give readings accurately reflecting the temperature of the fluid. You might try finding the heat sensors, and removing them and cleaning them. It could also be the MAP or MAF sensor. They can have delicate little wires, best cleaned by spraying, not touching.