The AC/heater (HVAC) system may unexpectedly switch to the defrost mode when accelerating. This system is operated by engine vacuum and should be inspected for any vacuum leaks if this problem develops. There is also a revised vacuum check valve available to address this concern.
Resources for the Repair and Maintenance of your 2003 Dodge Ram Van 3500
2003 Dodge Ram Van 3500
2003 Dodge Ram Van 3500 Problems
Some vehicles may exhibit one or more of the following: Spark knock complaints when the vehicle is under load, various single cylinder misfire, and surge in 4th gear (around 45 mph). Our technicians tell us that rerouting the coil and spark plug wires to minimize induction effects will commonly correct this condition. If wires must cross during the reroute procedure, they must cross at a 90 degree angle.
On 3.9L V6 and 5.9L V8 engines, the intake manifold gasket may leak and cause increased oil consumption and a spark knock during acceleration; the gasket should be replaced.
Leak detection pump failure can be caused by the internal diaphragm switch sticking, or in some cases, contamination from debris or carbon particles from vapor canister. If black carbon particles are present in the LDP, replace vapor canister in addition to LDP. The purge solenoid should also be checked for debris or carbon contamination and replaced as necessary. All evap system hoses are subject to cracking and splitting causing leaks, Inspe...
On the 3.9L V6 and 5.9L V8 the engine oil leaks at the distributor can be misdiagnosed as leaks from the intake manifold seal, oil pan gasket, or rear crankshaft (rear main) seal. A revised distributor is available if oil is found inside the distributor.
2003 Dodge Ram Van 3500 Questions and Answers
I hear a hi pitched whine when I accelerate WITH THE AIR CONDITIONING ON, then rises in pitch and fades in volume.
It stops when I turn AC off. What are the most likely culprits?
Thanks a million
2003 dodge w/ 5.9 cummins. oil leaks from crankcase breather where it goes into valve cover. It has new breather and o ring. Has 385000 miles very well maintained. No problems with performance runs...
i have a 2003 dodge 3500 van 5.9 won't start. codes po 340, po 645 and po 523 come up. I just gave it a mini tune up plugs and it ran for a day. now i changed cam postioning sensor still no av...