could it be converter problems
 

Been having problems with my 99 expedition for about two weeks now. It's been stalling, cutting off, and emitting black smoke from the tailpipe. I've gotten a t-valve put on and a tps sensor problem still persists. Does anyone think that it could be the catalytic converters?

I'm not sure what this "t-valve" is?

Is the PCM throwing any codes?

pdqford
 

yes,
I think it was showing codes for more that one thing. One of them was definitely the tps sensor. My boyfriend let his cousin run the check on it. I think one of the codes were for the converter also. I'm definitely thinking of buying me one of those code gadgets myself. I saw one for ford vehicles for 30.00 at o'reilly's. I can't explain what the t-valve is, but it was burned out. I had to go get it from the dealership, because thaey don't sell them at the part stores. My next route will be to replace the converters. my number 3 spark plug is stuck and needs to come out. I read that a foul plug can make the converter mess up. I also rode around for a long time with my #4 plug missing, because it was stuck also. Maybe this has caught up with me.