I have a 2003 Dodge Grand Caravan with the 3.3L. It has a consistent problem every time we start it. It runs super rough, has stalled a few times before, and makes a gargling noise. If you start it and give it gas, it mellows out around 2000 RPMs. If you try and drive it before revving it up, it will almost make a loud knocking noise.

It has the 2 codes 0300 and 0301. I have change the plugs, wires, and coil. I I have put Lucas fuel injector cleaner in every tank for the last 4 or 5 tanks. The problem persists.

I think i am loosing coolant cause the heater doesnt work sometimes and I have to add coolant to get it to work again.

The van runs really nice with lots of power once it gets going.

Im thinking head gasket but i cant find traces of coolant anywhere in the oil or on the ground.

Maybe a plugged injector (hope) and that its just running rough at start up.

Anyone have any suggestions?

 

Could try testing for coolant/oil contamination with a coolant combustion tester or test strips or use a coolant system pressure tester to check for leaks. Use a noid test light to verify the injector is getting it's pulse from the PCM. All of these are available to sign out from many parts stores.

http://www.obd-codes.com/p0300