I was wondering if you can/have to adjust the throttle positioning sensor on a computer controlled quadrajet. If you can I was wondering how you would do this. Thanks for your help.

Ben

 

Yeah you can. You need a special tool, and LOTS of luck to get the damn plug out. I've tried removing the plug on 4 different Qjets and haven't had any success yet.

 

Is adjustmet needed? and what do you mean by take the plug out. I just put new gaskets, ect in my ccc and replaced the tps. Are you refering to the plug that sticks out of the carb or possibly some kind of plug under the actual sensor inside? I dont think it would be possible to get the plug on the outside of the carb out without takeing it apart. It slides into grooves from the top. Oh, and this special tool, how much does it cost.

Thanks

Ben

 

There's a metal "plug" in the airhorn that covers the TPS adjustment screw, to keep backyard mechanics (like us) from dinking with it. It's located near the lever for the accellerator pump. I checked my pictures and don't have one that shows the location clearly. If I get some time this weekend I can take a picture for ya.

The tool is available from Thexton Tools--I think it's www.thextontools.com.

Yep, here's the part:

http://thexton.com/catalog/fuel/fuel_1.htm#No. 362

 

If you could get a pic, that would be great, because I could not find what you were talking about.

Thanks

Ben

 

i'm not sure that's the tps adjustment - you are talking about the throttle position sensor, right? as far as i know, either it's good, and works, or is bad and should be replaced - you can test it with a volt meter - as you move the throttle, the resistance should increase between two of the contacts - which, i don't know - if you search for tps in this forum, i'm pretty sure you can come up with the exact stuff - the thing that 99hawk120 is talking about is the highest part of the carb, right in the middle in front of the primaries flap opening - you pry that peice of metal out and underneat is a screw to adjust

 

What is that screw for, the cover is already off of mine. What does it adjust.

Thanks

 

i don't know very much about it, but it is...

15 - Air bleed valve assembly

on this page...
http://www.monte-list.nu/tech/qjetparts.shtml


how to set, beats me

 

Anyone else know?

 

maybe this will help...

http://www.darklair.com/monte/howto/...dle_screw.html

they talk about both, the idle mix and the air bleed screws


also, check out
http://www.montecarloss.com/technical.html
scroll down a bit to the fuel part, and there is alot for the qjets

 

Momar, u got mail.

 

Cool, thanks

Ben

 

Not sure what emails went back and forth behind the scenes but the screw in the pictures is the IAB (Idle Air Bypass) and essentially adjsuts the idle air/fuel mixture. It is totoally differet from the TPS adjsutment.

The TPS adjsutment is behind a small plug near the accerelator pump arm on the airhorn casting. Even if you remove the pug you still need a special tool to adjust it. In the vast majority of cases adjustment is not necessary. Just replace the TPS element itself inside the carb and it'll be very close to spec for both idle and WOT voltages.

Anyone can feel free to email me with qyestions about this as it is a sensitive adjsutment and many different things can affect it.

 

Ok, in that case, I have a new tps so I should be fine there. I am putting a 350 in place of my lg4 currently. I am using the ccc setup but am changing the knock sensor and esc module, and the secondary rods and hangers. I was wondering if I will have to adjust the IAB for it to run right on my 350. If so how will I get it set right.

Thanks again

Ben

 

You MAY need to adjust the IAB to get the idle mix right but before you get all worked up I'd put in on as-is and see how it runs. It will probably work just great with no adjustment.

The IAB can be accessed by removing the small metal anti-tamper plate from above the IAB adjustent. It is dead center between the primary bores, up on top of the carb just in front of the choke airhorn. Drill out the rivets on either side and you'll see the IAB adjustment below it. It screws in and out with a large regular screwdriver. Clockwise is richer, CCW is leaner. Move in small 1/4 turn steps and take a drive after each adjustment. Keep track of how far you have adjusted it so you can put it back to the initial setting if you get it "way out of whack" somehow.

 

Ok, I already had the rivits drilled out and knew where it was. I just wondered if there was a specific way of determining where it should be adjusted to.

Thanks

Ben