Modern electronic fuel-injection systems are some of the most trouble-free
systems in your vehicle. However, if your vehicle has accumulated more than
75,000 miles, there is some routine fuel-injection-system maintenance that
should be considered. The two most common maintenance jobs are fuel-injector
cleaning and throttle-body cleaning. Cleaning fuel injectors is generally not
a do-it-yourself project, but you can clean the throttle body on your vehicle
with common tools and specialized spray cleaners.
While throttle-body cleaning is good preventative maintenance, it should also
help engine drivability. In fact, if you've noticed a rough idle, stumbling
initial acceleration or even stalling - all when the engine is fully warmed up
- a dirty throttle body could be the culprit. Once you look inside a throttle
body, you will probably be surprised at the dirt, gum and varnish that have
accumulated there over time.
Park your vehicle outside in a well-lighted, level area. Because the
throttle-body cleaners are volatile, we do not recommend doing this job
Locate the throttle body under the hood in the engine compartment. Here are
some hints on what to look for:
Once you have located your vehicle's throttle body, look at how it is attached
to the air-intake tubes. Sometimes throttle bodies are attached with special
fasteners called Torx-head screws. If so, you will need Torx bits or Torx
screwdrivers to remove these fasteners. More commonly, a flat-blade or
Phillips-head screwdriver should do the trick.
The throttle body is located between the air cleaner and the intake manifold
of the engine.
Most throttle bodies are made of aluminum.
The throttle body is connected to the gas pedal of your vehicle with a linkage
or flexible cable, which moves the throttle shaft when the gas pedal is
depressed. (If you're having difficulty locating the throttle body, ask a
helper to press the accelerator - with the engine off - so you can see the
movement of the throttle shaft.)
There may be one or more electrical wires that connect to the throttle body.
Do not disturb these; for purposes of this project, you should not need to
disconnect any of these terminals.
While we always recommend that you follow all appropriate safety precautions
for these DIY projects, this is even more important for this project. Do not
smoke when you are working on your vehicle, wear all recommended skin and eye
protection and generally be aware that you are dealing with a flammable spray