I own a 2002 dodge grand caravan 3.3vl flex fuel. This pain in the a** has been giving me problems for about two month. It turns over just fine and I can drive it but when I do it starts shaking and hesitating on me. I have not been able to drive more than 15-20 mins, it does not turn of but the shaking and hesitating gets more aggressive. Also my RPMs are all over the place, with the transition in park it's at 2000, in drive it's at 600-700 and if I turn the AC on it's at 300. So far the codes I get from her are p0202 and p0508. Now to give you and idea of how much I have put in to this already here is a list go everything I have replace:

Cam shaft sensor
Crank shaft sensor
Idle air control sensor
Throttle position sensor
All 6 of the fuel injectors ( so p0202 makes me wonder)
Fuel injector harness ( it was damaged)
The throttle body has been cleaned

So as you can see I am very lost right now. If any body has any other ideas please let me know. All opinions are more than welcomed and appreciated.

 

What troubleshooting have you done to lead you to change all those parts? For instance, have you used a noid light on #2 to check for the injector driver pulse from the PCM? Have you checked the voltage input to the IAC from the PCM? Have you verified the IAC circuit is sound? Have you verified you don't have a vacuum leak?

BTW - Put the P0508 on the back burner. The IAC valve is only a factor when your foot is off the gas pedal.

 

Check the wire harness on the rear cylinder head. Its common for harness to melt on the 2002 to 2005 minivans. That harness is called a injector harness.