That screw should never be adjusted from factory set.

 

sometimes you have to adjust to make it run which was my case also when i bought the truck it had been adjusted and the idle air control valve was unhooked

 

No, you never adjust it. If it isn't running right something else is wrong.

 

as i just said it was adjusted before i got it kinda outta my control when i got the truck the iac was unhooked and idle screw adjusted to make it idle nothing i done personally maybe whoever owned it before me will read this post and catch on think i found a solution

 

so anyone got any suggestions about the code 34

 

ok i read on another site about setting the voltage at the tps and all i can get mine to is like -1.40 all the way to -4.00 anybody know anything bout this

 

Which is why you're getting the code. You want .90-.97 max.

87' should not have an adjustable TPS. I tried to install an adjustable TPS on my 87' & guess what code I ended up with?

 

If your throttle set screw is backed all the way out & your showing 1.40, implies the TPS is no good, or the wrong one.

Replace (w/ correct one) & take a closed throttle read. Keep screwing in the throttle set screw until you get a read between .90-.97 closed throttle.

 

i took a dremel tool and slotted the holes on the tps only way i could get the voltage to .98 was with the map and ps pressure sensor unhooked and it ran like **** plugged everthing up and unhooked the tps and it ran ok so i came to the conclusion it had to be that thanks for all the help still dont know bout the egr think im gonna replace the egr sensor and tps sensor an see what happens if that dont work might might put an aluminum intake and a 4 bbl carb on

 

Be very carful what you wish for! You can't be thinking straight! Sleep it off & we'll talk about it later.

Replace the TPS & we''ll address the EGR situation before you start buying anymore stuff. EGR & EVP function are not my favorite subjects. It's a dirty job...but somebody has to do it!