rough running on 1999 Mercury Mystique

changed timing belt on friends 2.0l 4 cyl.never drove car myself so i dont know how it was running before hand.had codes 300-301-171-1380 prior to my repair.belt was off gears and shreaded.ran good after repair for a short time but now has a bad miss at all rpm ranges.replaced plugs and tested wires - all ok (under 7 ohms)now i have the same codes up again after i reset them.any ideas?

by in Turlock, CA on November 25, 2010
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1 answer 1 comment
ANSWER by , November 25, 2010
P0300 and P0301 means - random misfire and cylinder one misfire. P0171 indicates lean with bank one oxygen sensor. P1380 is the key - it means: P1380 - Variable Cam Timing Solenoid A Circuit Malfunction. You likely have an issue with the VCT solenoid (not unusual with this model). The solenoid could require replacement - and at least needs looked into. I'm also concerned that your misfire is still present - compression test may be in order if the codes reoccur folloiwng repairs. Good luck and Happy Thanksgiving!
COMMENT by , November 26, 2010
thank you - i was afraid it was something in the VCT SYSTEM.