Hi!
My Crown Vic runs rough and misses on light acceleration, especially at slow speeds AFTER warmup. I do not have a temp guage, but I can tell it starts exactly the same time in daily commute to work, for example.
Car has 152k miles, 302, SEFI. Relatively new spark plugs and wires (8 months or so, maybe more)
Symptoms:
AFTER WARMUP misses on light accel from stop, but goes great if you stomp on it idles rough for a bit after warm restart feels like timing is being "thrown around" miss can be felt at cruise speeds, but acceleration is still good even runs without missing warm, sometimes, or for a while, like it's "in the groove"
#5 cylinder fouls, but compression tests good 165/185 dry/wet
runs very smooth cold (minnesota cold) starts right away cold
Diagnostics:
No codes, but I recently replaced the EVP sensor which was bad (codes) in hopes of alleviating these symptoms.
Cannot hear or find any vacuum leaks.
Checked wire routing carefully for the old 7/8 crossover problem.
Actions:
I have an identical engine in a 1989 Colony Park Wagon that runs PERFECTLY (smoothest 302 I ever had)
swapped entire distributor and tfi module assembly swapped primary coil swapped egr valve swapped throttle position sensor
replaced #5 plug twice replaced #5 spark plug wire
installed new oxy sensors
Next on the list:
MAP Sensor? MAF Sensors? Temp Sending Unit? Knock Sensor? Injector? If injector bad, I would expect constant miss, not after warmup.
Any and all help appreciated!!
Thanks,
Mark
Crown Vic Victoria engine misses missing hesitates hesitation idles rough idling