intermittent "miss"

[Tio Carlos]

My '05 XLT developed an intermittent "miss" when idleing after about 2000 miles. It has gotten consistently worse. Ford Place has diagnosed it 4 times and put their "black flight control box" on it with no problem found. They did service the injectors (the claim), but the problem persists. Sometimes, the engine misses do bad that it shakes the whole vehicle. I've heard that the ignition coil might be the culprit. Anybody got any ideas?
Thanks,

Tio Carlos

 

[cjones101812]

was it misfiring at the dealer??

do you have a check engine light on??

does the check engine light flash when it misfires??

is it only while idling??

what do you mean 'after 2000 miles?? after driving that distance?? you have 2000 on the odometer??

scanners have a function to see which cyl/cyls are misfiring and how many times they misfire.

does it do it worse when hot??

which engine do you have?? 4x4 or 4x2??

 

[Tio Carlos]

Misfired at dealer, no check engine light on or flashing, only while idleing, "after 2000 miles" means the problem developed after the veh had about 2000 miles on it. It has 26500 now (been a problem for almost 2 yrs.) Scanners show nothing...and I mean nothing. Engine will miss from a cold start or after driving for as little as 10 min. or as much a 2 hours. Engine is V6 and it's a 4x2. What's aggravating is the service mgr. can see, hear and feel the miss, but has no clue what to do. Thanks for your help.

 

[cjones101812]

have you checked the compression??

a cyl. balance test??

EGR system??

did they put it on an osciloscope??

i've used a SmartTach Plus by Matco Tools to check for misses. it looks at the spark voltage needed to fire the plug.

is the CKP sensor loose?? or the trigger wheel bent??

is the CMP sensor loose??

i assume they already changed the plugs, changed/tested wires.

fuel pressure??

hows the charging system(Alternator) and battery??

did they/you check all the grounds??

i know these are a bit random but i'm writing as i think of them.

you may want to look into the Lemon Law out where you are, if they can't fix this.

 

[Tio Carlos]

The Ford Dealer analyzer checked all those variables with no sign of a problem. And...I am considering the Lemon Law solution if this thing isn't fixed soon. I'm going to give another dealer one more try.
Thanks\