Chevy 2003 Trail Blazer ls
question = When i turn on my a/c and let it idle the rpm dips way below 1 and almost shuts off until i
rev it up again but if i let it sit there it shuts off, it does the same thing when i turn on the heat, other
than that the engine is fine, but only when the a/c and heat get turned on it starts to die, i just
changed out my battery as well so i have a new battery, also with that my power buttons on my
door don't work from time to time, and i wonder if they are related to each other.
Answer: OK. This is a very common problem when there is carbon buildup in
the throttle body bore and plate. Suggest a good cleaning. The throttle body
is the front top of engine that the air cleaner duct hooks up to. Remove the
duct, open the throttle blade, spray some carburetor or carbon cleaner from
any parts store all around the bore and plate. Then spray some on a rag-
not a paper towel, and wipe all around the bore and plate. Re-install duct
and start the engine. It will run rough for a few second. Rev it up a few times
to "Clear it out". Then take for a short ride doing a few hard accelerations.
Shut truck off for 2-3 minutes, then start ans let idle. After this, the idle
should be fine." The window problem may be in the switch itself. If this is the
problem, a new switch would need to be programmed after replacement.
2004 Chevrolet Trailblazer.6 cylinders.
Warning lights: service. Repairs for this problem = changed battery.
Question = I start the engine, when a turn the air conditioner on the rpm dips or the engine shuts off. The idle
don't stay normal.
Answer: The problem you are experiencing is very normal for these vehicles.
What is happening is that there is an airflow restriction at the throttle body due to
carbon build up. This occurs over the years as a result of bad gasoline, hard
driving, lack of maintenance, etc. What you need to do is remove the air ducting
to the throttle body and then with a good solvent based cleaner, clean the
throttle body very good including the throttle blade and all inside the throttle
opening. Most auto parts stores have a good cleaner for this purpose. You really
have to get in there good and clean extremely well to solve this issue. If you
have compressed air, that be a help too in drying out the throttle body after
cleaning. Once it is clean, reinstall all the ducting, reconnect any sensors, etc,
and start the vehicle. If you got any cleaner inside the intake it will burn off
almost immediately, but can cause the vehicle to run rough for a minute. Once
the vehicle has reached operating temperature, take it for a short drive. This is
required so that the computer can 'relearn' a new idle speed. After that, you
should be able to use your air conditioning, defroster, etc, without any problems
at all.
2005 Chevy Trailblazer 4.2L
Repairs for this problem = air intake temperature sensor and throttle body clean.
Question = Tune up the truck replaced everything back i had to disconnect the resonator and connect it
back to reach spark plugs when i start it runs smoothly but when i turn on the ac rpms run low, engine
shakes, stalls, then powers up and stalls again then finally dies with the fan still blowing.  I took it to
check battery and alternator i got a diagnostic and no warnings popped out everything was good so no
idea what is wrong why does it die after i turn on the ac?
Answer: It is stalling out when you turn the A/C on due to the engine not
getting enough air when the idle raises to compensate for the air
compressor kicking on. This is almost always fixed by cleaning the throttle
body. If you already did this, you didn't do a good enough job. You have to
really get in there and clean around and behind the throttle plate. Any little
carbon left behind will still cause issues. You should take the air intake off
again and re-clean the throttle body really good with a product called 'brake
clean'. After reassembly, start the vehicle and rev it up to burn out any
excess cleaner, and then take it for a drive. It will take a little bit for the
vehicle to re-learn the idle again, but it will be fixed after that.

Chevy Trailblazer Dies Out With A/C

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