Throttle body only 80% at WOT?

colosilverado · February 13, 2002

I read somewhere else that the '99-02 trucks throttle body blade is only open about 80% at WOT. They mentioned some grinding can be done to help open it up and they mentioned some other "free" mods.

Just in case any of you is the adventurous type.

TB Mod

If someone does this, let me know us know how it works.

mnstrmdnss · February 14, 2002

that sounds like another good mod to try out, im gonna check out my throttle body as soon as the temps outside warm up a tad, cause i also say "every little bit counts".

RacerX · February 15, 2002

The TB mod is only good for the trucks that do not have throttle by wire (trucks without traction control). The throttle by wire opens the TB 100%.

CMNTMXR81 · February 18, 2002

The LS1 guys do this as a mod. What you do is grind down the stop so that the throttle opens further. CAUTION THOUGH!!! At WOT, the PCM should read 4.7volts (or kilavolts, can't remember which) and if you exceed this by too much, it'll set an SES light.

The proper way to do this is not to necessarily look at how much percent open the throttle blade is, but rather that voltage I spoke of before.

Example, if you go do a WOT run and scan it at the same time, log the throttle position sensor voltage. Let's say it says 4.6volts at WOT, go back grind it down a little more. Go do anther run. Keep doing this until you get to the 4.7. Even at 4.7, you still may get a reading saying the throttle blade is 95% of the way open.

Dihappy · February 18, 2002

Too high tech for me

Where ad what do you use to analyze the 4.7 v??

RedHawk · February 18, 2002

Yeah, it is 4.6 volts.. Use a volt meter across the blue and black wires going into the drivers side of thje throttle body..Have someone push the gas pedal down to the floor and measure the voltage..Grind were the throttle cabel cam arm hits the stop on the throttle body , until you have just under 4.6 volts.

02EnvoySLT · February 19, 2002

... if you need grind more at the tab to get it horizontal and you're at the 4.6v limit, then you can take off the TPS sensor and enlarge the holes carefully so you can cock the sensor to display a lower voltage or max of 4.6v fully horizontal TB. Check the idle (closed TB) voltage after a full key cycle once you are done adjusting the sensor. The PCM resets the closed position %.