Issues While Starting Engine

[ralphpolo88]

There are times when I turn the key and the engine turns just fine, but then it kind of sputters until it starts. This is usually after the car has been sitting overnight or when it's been sitting all day. When it doesn't do this, the engine will turn and then the engine will fire up at ~1500 RPM and then gradually go down as the engine warms up. However, when it does happen, the engine will turn and then the tachometer will rise from ~500 RPM and climb to ~1500 RPM. I'm sure I'm not explaining it very well, but it just doesn't feel normal since it doesn't start that way all the time.

Also, I took my car in for a 20k service and they said my battery was bad and replaced it under warranty. The problem I described occurred with the old battery and the new battery too.

I was just wondering if anyone has experienced anything similar.

 

[GrantK]

I hate these types of gremlins, they can be a real PIA to figure out.
One thing to try is when you are starting the engine, turn the key to on, wait a few seconds then turn the key all the way to start. This makes sure the fuel system is up to full pressure and while not likely to be the problem, it help eliminate it from the list of possibles.

Another thing to try is to get a ODB data logger and leave it plugged into the truck through several occurrences of the problem then check to see if it logged any errors.