Gasoline direct injection or GDI for short. This is an awsome new (well diesels have been using this forever) fuel injection system now being used on a good majority of new vehicles to help increase fuel efficiency, lower emissions, and increase horsepower. Does it work? Yes it does and it works very well. However there is one drawback. This system requires extra maintenance that If not done will result in major engine problems.

Carboned up intake valves of a GDI engine with 45k miles.

Carbon build up on intake valves of a GDI engine with 45k miles.

Without getting too technical. Before GDI systems became the norm we used port fuel injection (many new cars still do) and there is nothing wrong with port fuel injection. In fact it works VERY well and doesn’t require the extra maintenance to keep your intake valves clean because it is continuously spraying fuel directly onto the intake valves keeping them nice and clean like so.

port fuel injection, clean valves

port fuel injection, clean valves

The advantage of GDI as described earlier is better Fuel efficiency, more power, and lower emissions. These are good enough reasons alone for car manufacturers to make the switch.

The Bad: as seen in the second picture in this article the valve are VERY dirty and will cause issues with airflow, the carbon build up will also cause poor engine sealing which will cause misfires, it can also cause valve guides to wear which results in oil consumption, noises, and valve train instability (running rough, bad idle, misfires). Let me be clear. If you don’t take the steps to prevent this you are looking at the top half of your engine (cylinder head) needing to be removed and rebuilt, this will cost you at least 2 grand.

Maintenance:¬†To prevent any of the above problems from happening you simply need to get an induction/valve system cleaning performed on your vehicle every 15-30k miles (personally i would do it every other oil change). The average cost for a shop to perform this is about $60-$120 dollars (just make sure it’s an induction service not injection service). The good news is that this service is fairly simple to do and almost anyone can do it them selves after watching a youtube video, reading instructions and buying the inexpensive solution needed. I provided a video showing how easy it is to use. Here is the stuff you need CLICK HERE¬†from amazon with free shipping.