I just did opti / wp swap and the car is very hard to start.. it cranks very very slowly for the first 2 tries and the lights dim.. and then it'll just fire right up... Its just fine while driving xcellent actually... but at idle it'll try n hold 900 ish rpm but every couple seconds drop to round 625 for a split second and almost stall and does stall sometimes. Could a bad plug wire cause this???? Because the old opti had corrosion in cyl8 terminal and i haven't got arround to doing the wires yet. SOO happy not to have that 3000 rmp stumble anymore from the opti but this stalling isn't fun now....

 

Maybe a failing alternator thats causing the stalling?

 

When I was replacing the belt it felt like the alt did hav some play in the pulley. and new belt also alot more tension on it