I'd say plugged cats. Had the same problem and the cats were plugged too. Related? not entirely sure but I wouldn't be suprised. I always thought this is why I had problems.
Green 96 mystique gs 4cyl mtx
16.9 in the 1/4 mile @102500 miles
95SE in Midnight Red MTX
MSDS headers and y-pipe
SVT exhaust
SVT UIM
Optimized se TB.
Full pre 98 SVT body kit
15.741 @ 87.73mph :)
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