Originally Posted by m7ammed
Having the same issue, don't want to open a new thread. My car has 113,000 km on it (70k miles) and the past week the weather got colder and I'm starting to have some problems on cold starts.
I'm thinking of replacing all 6 Injector/Coils/Spark plugs. is that a good idea? or is it better to let the dealer check which ones are faulty? the car doesn't show any lights/faults, so not sure if they will find anything.
Also I've asked the dealer about intake valve cleaning and they said it is a big job they to remove the head or something, so that's going to cost alot. is it OK to do the replacements, without doing the cleaning?
The intake valve cleaning is not that big of a job. The only primary component that has to be removed is the intake manifold. After that comes the tedious task of cleaning each port where the valves are closed then rotating the engine over and cleaning the next set of closed valves. The cleaning procedure has to be done when the valves are closed so all of the carbon gunk and cleaner doesn't get washed into the combustion chamber. Most dealers charge the labor time for r&i intake manifold plus an additional 1.5-2 hours of labor for the cleaning.
Also, I wouldn't shotgun all new coils, plugs and injectors. That's way to costly for something that isn't that hard to diagnose. Usually coils and plugs tend to misfire when hot. Most likely you have carbon buildup or injector issues (or both). Check the part #'s on your injectors. If the last 3 digits of the part # are 138 then there is a good chance they're failed. The last 3 digits of the current injector part #'s are 261, and while those still fail on occasion, it is far less common.