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W-Body Performance - Pushrod / DOHC
TTs - Throttle Body Cleaning

"...Sounds like you've got a frog stuck in your throat!"

So, you car idle like there's something blocking the way huh?  Let me guess, you've replaced the air filter and stuck in some premium gas to improve the problem but with no luck huh?  Maybe you have poor throttle response?  Sounds like a dirty and clogged throttle body.  Over time, particles due collect to the butterfly plate due to old dirty filters, and recirculated gases from the Positive Crankcase Ventalation (PCV) valve.  This simple cleaning procedure will help increase throttle response and promote better mileage.

1.)  Run car up to normal operating tempretures before proceding to next step; car should be warm so that short-termed, high RPM's are achieved so thermo-expansion damage do not occur during cleaning process.
2.)  Shut off car and remove the intake tube that connects the airbox to the upper intake plenum.  Try to keep (if possible) sensors connected and pluged in with the tube moved.
3.)  Start car and with help of a buddy or your other hand, keep the car running while spraying the throttle body with approved fuel injector throttle body cleaner.  While spraying the car will studder and may tend to die out; keep it running by giving the engine gas to shoot up to the RPM's.  Let the RPM's rise and fall to increase cleaning effectness.
4.)  Spray throttle untill can is out or untill throttle is clean.  ** During cleaning you may see a gray or black smoke coming from the exhaust; that's okay.  The motor is buring off the cleaner and the deposits removed from the throttle body and intake manifold.  Also, it's possible for the Service Engine Soon (SES) Light  to show up on the instrument panel; don't freak out.  Since the intake tube was removed out of the way from the directed air flow, the Mass Air Flow (MAF, if equipped) sensor is not having air pass by and in-turn the car's computer is not recieving a signal.  This can be reset once after the procedure is done. **
5.)  Once throttle body is cleaned, shut off car and re-install intake tube to plenum and airbox.
6.)  Restart car and check to see if the SES light is on / off.  If off, you're cleaning procedure is complete.  If on, pull either the ECM fuse or the negative battery cable and let sit overnight.  This should reset the computer to factory specs and removing the SES light.
7.)  After procedure, it's recommended to replace air filter with new one and top off gas tank and add in a fuel injector cleaner.  This should help bring idle and accleration life back to your vehicle.

- Average Time:  30+ minutes
- Scheduled Maintenance:  every 15K or if noticing poor throttle response / accleration
- Price of Materials:  throttle body cleaner ~ $3.50+
                                     fuel injector / system cleaner (recommended after) ~ $3.00+
- Written by Erik Melander