2003 crown vic p71 rough idle

[boogiecrownvic]

i have a 2003 crown vic and when i start it up its has a rough idle it continues to do so during and after driving and there is also a light chirping like sound it seem like it is coming from one of my pulleys. please help i dnt kno wat to do about the idle

[stone42]

sounds like dirty fuel injectors or a vacuum leak. is the check engine light on?

[BroncoJoe19]

One probably has nothing to do with the other. (the chirping sound and the rough idle)

Your engine is computer controlled and it runs self checking software all the time it is running. One needs a computer scan tool to pull diagnsotic codes out of the computer. Many (especially the large chain) auto parts stores will pull codes for you for free. Get your codes and come back.


There are two pullys that usually wear sooner than the others. The idler and tensioner pully. There is a decal on your radiator cover/cowel that shows how the "fan" belt runs. It probably labels the two pullies. Be sure not to be wearing any loose clothing, chains, long hair, or anything that could get caught in a moveing part. Then one may use a piece of garden hose, or a carboard tube (gift wrap) to listen for the offending pully. Sometimes a long screwdriver held to the center of it, and then to the ear, one can hear it.

Another way is to remove the serpentine belt, and then giove each of your pullies a spin. One will usually be able to feel the difference.
Usually when I replace one pully (tensioner or idler) I'll replace the other as well. Tehy eahc have the same number of revolutions on them, and one should be right behind the other in need of replacing.

[boogiecrownvic]

my check engine light is not on but i will get the codes and come back thanks

[theoldwizard]

Just because the check engine light is NOT on, does not mean that the computer does not have some stored error code.

The light is only required to be turned on if there is a problem that effects emissions or safety.

[boogiecrownvic]

someone told me that i simply need a tune up could that be it

[BroncoJoe19]

yep... could also be a bad coil over wire, vacuum leak, bad TPS or bad Engine Coolent Temp sensor.
SO I don't know what you want to do.

What's entailed in your friend's tuneup? and how many miles do you have on your car. also are they highway miles, NYC type stop and go traffic?

Your Cap, rotor, and plugs should last approx 100,000 highway miles.

[boogiecrownvic]

i have about 86000 and they are mostly highway mile and some stop and go and i was just told new spark plugs and coil on plugs with the tune up i just had my oil change around last week

[BroncoJoe19]

Those coil on wires are about $50-$60 each, you have eight of them.

If any is bad, it should throw a diagnostic code. That code tells which cyl is misfireing. I have 150,000 on my crown vic, and so far replaced three of them.

So... you can pull codes and only replace broken parts, or do a gradual replacement of all of your sensors and actuators, kind of preventive maintenance.

AS part of a preventive matenance, don't neglect your transmission. And getting your injectors cleaned may be worthwhile.

[boogiecrownvic]

thanks im goin to take my car to advanced auto parts and see if they can hook it up to
a diagnostic machine and pull the codes for me so i can have my mechanic repare what ever it is