How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Clayso Your Own Question
Clayso, Master Automobile Technician
Category: Dodge
Satisfied Customers: 880
Experience:  ASE Master Certified Automobile Technician. 30 Years Experience.
Type Your Dodge Question Here...
Clayso is online now
A new question is answered every 9 seconds

Engine code p0440 evap system (small leak detected). seems

Customer Question

engine code p0440 evap system (small leak detected). seems to be running a tad rich also. alittle build up the end of my exhaust tips on the body.
JA: How many miles are on the car? Have any warning codes popped up?
Customer: 185k, and just that one. my catalytic converters went out on me and I had to cut them off. but I ordered new ones just haven't had them put back on. but the engine light was on before that. same code
JA: What is the model/year of your Dodge?
Customer: 2003 1500 4.7
JA: Are you fixing your vehicle yourself? What have you tried so far?
Customer: haven't tried anything with evap system yet. Ive ran fuel injector cleaner thru it to see if that helped the running rich issue. doesn't seem so though.
JA: Anything else you want the mechanic to know before I connect you?
Customer: that's all ive got right now
Submitted: 1 year ago.
Category: Dodge
Expert:  Clayso replied 1 year ago.

Hi There,
This is Clay, I'm a certified master automobile technician with 30 years of automotive repair and diagnostic experience.

P0440 most commonly sets for the Natural Vacuum Leak Detection (NVLD) assembly on this vehicle. The NVLD is located next to the EVAP canister in front of the fuel tank. A voltmeter and a hand vacuum pump are required to test the NVLD. It would also be a good idea to have the EVAP and intake smoked checked for any vacuum leaks. The NVLD device is designed with a normally open vacuum switch, a normally closed solenoid, and a seal, which is actuated by both the solenoid and a diaphragm. The normally open vacuum switch will close with about 1" hg in the evaporative system.

Without converters I'd expect the system to be running rich, there is no change in the exhaust gases for the dowstream O2 to make comparisons with. Any and all vacuum leaks will cause a rich running condition. Basically the PCM adds more fuel to compensate for the additional intake of air not regulated and monitored at the throttle body. That being said I'd say the vacuum leak may also be a cause for the converter failures.

I hope this information is helpful. If you have any questions let me know. You can reply back to me through this thread at any time.

Kindly rate my assistance in a positive manner so I may have credit for helping you.
Positive ratings are greatly appreciated.