Car Questions
RepairPal is your advocate for car care advice and guidance

2000 4.6l

(2000 Ford Mustang)
in Clarksville, TN on March 04, 2009
my car backfired last night when i attemped to start and now it will not sty running. and pops even few attempts. What is causing this?
Displaying 1 answers & 4 comments
Popular Answer
on March 04, 2009
do you have any warning lights illuminated? (is the check engine light on?)
on March 04, 2009
do you know what the trouble code is? I will try to help if you have the specific code
on March 04, 2009
Code P0442 is "EVAP Control System Small Leak Detected"

This can be a difficult code to chase down on your own. Most smog repair shops have a "small leak detector" or what many techs call a "smoke tester". Smoke is injected into the EVAP system and the shop uses a very bright light to watch for the smoke.

The description for this trouble code says a loose gas cap can cause this code to be set but I kinda doubt it would also cause the backfiring/stumbling problem. Make sure your gas cap is all the way tight and not accidentally cross threaded. If the cap is tweaked slightly it won't seal completely and lead to this 'small leak'. Smog shops here in CA have a machine that will test gas caps for sealing ability if you're not sure about your cap's condition.

Simple visual checks you can do in the engine compartment include making sure your air intake tube doesn't have any cracks or holes, no dangling or melted vacuum lines. If you're comfortable doing this, you can spray brake clean around the intake gaskets and hose fittings and see if the idle changes. Many techs use this to chase down leaks quickly.

There is a service bulletin from Ford that describes the diagnosis procedures for this DTC (diagnostic trouble code) but the first step is to connect the smoke machine and scan tool.

hope this helps, I wish I had an easier fix for you.
on March 04, 2009
I should mention that you should be careful about what you spray the brake clean on. Try to not hit wires or connectors and avoid soaking sensors on the throttle body
on March 04, 2009
yes, auto zone said there was a vacuum leak and we could not find one any where-

Code 0442 emission
RepairPal estimates are guaranteed at over 2,000 quality certified locations nationwide. Learn more

Similar Questions

View answers to similar questions from RepairPal's community of auto experts and enthusiasts.
at this mileage does timing belt and water pump need to be replaced
was at idle when it first happen pull over and it quit smoking now only doing it when I start in after not running fo...
Didn't find what you were looking for?