Is this normal? Some mornings when I start the car it's obviously cold after being left overnight and there's no trouble cranking or starting the car but when you crank it you hear and feel a rumble or two (almost sounds like mini explosions in the engine) before the car starts right up as usual. Does anyone else get those rumbles too and know what they are and whether they're normal?

When the engine is warm, I never get this. So when I'm leaving work and I go to start it up since the car has only been off for about eight hours it starts up with no rumbling and the start up sounds nice and clean.

There's no issue with actually starting the car, I never have no starts or have to crank longer than two seconds, it's just the sounds and the shaking make me suspicious.

 

Which car are we talking about? There's 2 different cars in your signature.

 

The '09. Actually the rumble is more like a sputter from the engine until it catches on and idles. The same sputter also happens if you shut the car off.

 

how long does this sputter happen for, and after your let go of the key (after starting) how long does it persist? And is it like it is stumbling? - ie. hitting on two cylinders? which would make it shake and "stumble"

 

For about half a second. Like for the '95 when you turn the key to off, the whole car just shuts off quietly. For the '09 when you turn the key to off, for about a half second or slightly more the car vibrates/rumbles/sputters and then shuts off. It's not as smooth. This same effect happens at cold start.

At cold start:
1. I turn the key to ON.
2. It goes rrr rrr (cranking sound).
3. Within 1-2 seconds the car starts with a vibrate/rumble/sputter, idle shoots way up then lowers immediately.
4. I let go of key.