I have a 2001 Crown Vic Police Interceptor with 198K miles.
I've been dealing with this stumbling problem for at least a year if not more. It seems like this is a common problem. It doesn't throw any codes. I've tried to get real time readings with my code reader and nothing.
It stumbles at the usual 45-50 mphs in 4th with part throttle or at lower speeds in lower gears going up a grade. It happens more with passengers. It doesn't always do it. It even seems to stumble a bit at WOT. It sort of feels like its not getting enough fuel.
It most of the times runs great and gets around 18 mpgs in combined driving.
I've changed the fuel and air filters. I've changed the plugs and cleaned the MAF. I've cleaned all the electrical connections at the coils. The coils are OEM but I don't know how old they really are. They have green Motorcraft logos on them. Visually they look fine as well as the boots.
I'm leaning toward needing coils but I've read it could be the MAF or the TPS. I don't have money to throw at guesses. I really want to solve this once and for all. I used a good quality Matco code reader and was even trying to get soft codes but got nothing. It's frustrating.
Edited by Old car fan, 04 December 2016 - 03:24 PM.