Posted: Fri Sep 29, 2006 3:10 am
Ok... I see what you mean.2k2patriotblueneon wrote:Because thats adjusting the actual fuel and air being delivered on idle. If you want to correct the stumble you should drill the hole and it will only adjust air saving a very small amount of fuel as opposed to your way. Your way isn't really a fix per say its just like holding the gas pedal down a tiney bit to keep it running.Neonisti2000 wrote:Little off-topic...but:skuttler wrote:I hope you mean 600 rpms. Thats relatively normal. I drilled a 1/8" hole in my throttle body to increase idle just a bit. might be worth a try.
- Why drill a small hole to the throttle body butterfly"valve"....?
I've got the 5-speed with the stock throttle body and it's got an adjustment screw right under the place where the accelerator cable connects the throt body.
By adjusting the screw, you can control the amount of air that passes throt body valve when when it's closed or near it. In other words, you can adjust the engines idle.
You can't see or adjust the screw unless you take the filter box off but after that it's easy to see...
So, because the throt body shaft's other end connects to the TPS, it sends a signal to PCM of it's new position and PCM increases fuel flow to match icreased air flow...
But isn't the change so minimal that if fuel flow increases, it increases only so little that it's barely noticeable in consumption?
Of course if you raise the screw too much, it doesn't do good either...RPM's go wild and doesn't come down like should when foot is off the pedal...
And last time when I cleaned my throt body, IAC and TP sensors, I noticed that the butterflyvalve in TB was a little sticky. So, I used the screw to adjust it a little and after that it worked again nicely.... Not sticky anymore. There was no carb residue...just was misadjusted.
About the stumble... Isn't it a fuel flow control issue rather than problem with the air coming through TB...?
E.g if car stumbles when coming to a stop, problem is in PCM/fuel flow. It's the fuel saving program that they put in the factory to save in fuel costs...
So, that in mind, it's then a good thing to use the adjustscrew (although best would be the PCM flash) to "manually" adjust it/idle. Even if it raises the fuel flow, it's a good thing cause now your car won't stumble....
