Service engine soon light is on (1999 Grand Caravan) - Code 55

Its mostly fule related. Start checking these issues;
Intake air leaks
Faulty front heated oxygen sensor
Ignition misfiring
Faulty fuel injectors
Exhaust gas leaks
Incorrect fuel pressure
Lack of fuel
Faulty Mass Air Flow (MAF) sensor
Incorrect Positive Crankcase Ventilation (PCV) hose connection
My guess would be the PCV or MAF.

P0685 DODGE - Auto Shutdown Relay Control Circuit Failure
Possible causes - Faulty Engine Control Module (ECM) power relay
- ECM power relay harness is open or shorted
- ECM power relay circuit poor electrical connection
- Faulty (ECM
Possible symptoms:
Engine Light ON (or Service Engine Soon Warning Light) P0685 Dodge Description: Short or open in Auto Shutdown (ASD) relay circuit, this relay is under the hood in the relay center.

You first need to tell us what the error code (s) is. The injector and gas cap are two completely different issues. Get it scanned and come back with that information.

Take it to Advance Auto Parts, or Auto Zone, they will scan your computer for free to get the code and tell you what it means. May just be a sensor, or the gas cap isn't tight (emissions) may or may not be serious. Thanks.

get someone with a code reader to see what it is telling you.

this is what your check engine light was telling you. code 12 battery input was disconnected within the last 50 key-on cycles. code 54 no camshaft signal detected during engine cranking. code 55 completion of fault code display on check engine lite. hope this will help you!! note: camshaft sensor is located in distributor on 3.0liter engine and on a 3.3liter and 3.8 liter engines its located next to the thermostat housing.

sounds like you have a vent valve problem, po440 is that something is wrong with evap system, which vent valve is part of, start by checking that first make sure its not blocked with spider webing,good luck.

disconnect the battery for a minute reconnect start it up light should be off thanks pierre

a i got a 1996 with the 3.8 dodge caravan and the codes red 12 and 55 my car wont start at all got gas in it

ENSURE THE AIR PRESSURE IN ALL 4 TIRES ARE THE SAME. CHRYSLER UNWITTINGLY HAS A TPMS (Tire Pressure Monitor System) by having an ABS light.
When 1 tire turns slower (or faster) than the other 3, the ABS lamp illuminates when it thinks the wheels aren't turning the same speed, (they aren't). When properly inflated, (or all 4 at least at the same pressure, the ABS Lamp will go out soon, (not immediately). Maybe on the next drive cycle.