Topic: 4.6 RUNNING BAD

[97,01 mustangs]

i have a97 stang start up cold take off runs its ass off as soon as gets warm car starts falling on face missing when driving any answers.

[Soaring]

Clean your MAF and clean your K&N filter then get back if that doesn't fix it.  You may not be getting enough cold air after it warms up.  I just cleaned mine today on my 03 Mach, and she runs like a scared rabbit.   

[97,01 mustangs]

i cleaned maf and i took one off my buddys stang and car was still the same looked for a vaccum leak checked fuel press and fire still nothing

[Soaring]

Take that Mustang into a Ford repair shop and have them run the codes.  It is hard to "guess" what is wrong here on the internet. 

[97,01 mustangs]

i have a scan tool and ran codes all come back good took the car to ford talked to a mech and he told me to try a couple things did them all so i went up to ford when he got off and he drove my stang his head turned to the side like a dog and a I DONT KNOW. WOW RIGHT he said that no one in shop has seen a 4.6 do that before thay are lost to

[Soaring]

And you expect us to analyze the problem online?    Don't get me wrong, but we can't help you without more information. 

[97,01 mustangs]

nope just looking to see if any one has had this problem. im thinking omost time to sell........

[Konrad]

If it is capable for running fine when it's cold, then mechanically there must be nothing wrong with it. There must be a computer/sensor issue which will show up when it warms up and goes into open loop mode. As to what it is, i haven't got a clue.

[fencer]

Same thing with my 96 4.6 runs perfect when cold misses at operating temp turned out when intake was changed didn't clean out coolant from #1 #2 spark plugs as the plugs where changed right before intake started leaking.Now it runs perfect

[Soaring]

Again, run the codes.  It could be defective coils when they get hot. 

[kingaustin3606]

damn. yeah couldnt tell ya