Help!! Engine Problems!!!

I have a 98 Mercury Moutaineer with the 5.0L engine. Started having problems at 100,000 miles. Engine starts and idles just fine, but while driving, (expecially on SLOW accelleration) the engine chugs very bad. When engine is in high RPM's, (above 4,000) it runs good, but you can hear a little bit of misfire still happening. Check Engine light is on CONSTANTLY. Took to for garage and led me around many different fix's. Fuel filter, plugs/wires, throttle sensor - nothing helped. Last thing they suggested was the catalytic converter. Replacement is $1,200! Friend is having same problem and replacing cat/converter did not help. Is anyone smarter than the local Ford garage?????

Maybe it's time for you to learn how to get the error codes and do some of your own research. I wonder how the Ford dealer came to the conclusions of why they did what they did? Did an error code indicate that the catalytic convertor was restricted? Did they give it to you to keep? There isn't trade-in value on a cat convertor. Look to see if the old one was plugged? They're supposed to be the experts, not just experimental parts changers. Hell, anybody can just keep installing new parts until the problem is gone!

one you should not continue to pay for repairs made that didn't repair a problem - you need to talk to the dealership manager and come to an agreement on the cost to you - and two - if it was a motorcraft part the old cat does have a core value and you need to go and inspect it quicly before it is sent back

the code that came up is i beleave 143 im not sure but on many fords that code comes up alot i have a 12 grand marquis and theres many problms that the code sugests which is stupid but i was told the best place to start was the o2 scensors id say try that and check for vacum leaks also

Uhh...I work at a ford dealership and haven't heard of a 143 code...I just checked our listings and it doesn't exist. If you're talking hegos and vacuum leaks you're probably thinking P0171/174

yesa thats the one im thinkin of