How do you test if an injector is bad? My wife 98 XC is getting very hard to start and is puffing smoke when it does start up. The problem started out intermittent and has become almost a constant. I have had the engine 'moto-vaced' and have replaced the fuel filter. The problem got marginally better after the vac and filter, but not all the way there and is not getting bad again. The car is acting like it flooded when you try and start it so I am thinking I have a bad injector that is flooding the engine ??.

On a side note, I checked the codes last weekend and came up with a P0116 - Engine Coolant sensor. I will replace the sensor and t-stat this weekend, but I don't think the two things are related since it starting having problems before the CEL came on.

Any help is greatly appreciated.

Kevin