this did nothing for my MPG and it screwed with my shift points, I would avoid... I went back to a stock throttle body after about 2 months of driving with a modified one...

 

Hmmm thats odd , ive done it to my blazer and s10 and never caused problems just made my gas response alittle better in my opinion.

 

I did the throttle mod it definitely helped with throttle response my next question is if i unplugged my egr would that help at all? I read that thats what that little plate on the throttle blade was for to help the egr blend the gasses with fresh air and could the pcv valve cause bad mpg a buddy of mine who is a mechanic said he heard of a guy with the same motor eating pcv valves every 6months and that it just blowing by can cause bad mpg

 

Problems with your vacuum system can lower your mileage. In post #3 you mentioned that it's stalling when you hit the brakes and the 4x4 vac lines are broken and plugged. I'd get those two systems working correctly and see where the mileage is before I modified any other system. Since you're sacrificing mileage to have 4 wd it only makes sense to have it working.

 

Consider this:

The flap on the throttle plate that you're removing restricts airflow so that as you ease into the throttle the engine doesn't jump up in RPM's and cause the vehicle to serge and jump forward, something the average driver doesn't want, which is why GM designed it as such. That explains why removing it gives more throttle response; it allows more air to enter the engine right away when the throttle is cracked, thus allowing the engine to serge to life.

However think about how the rest of the engine running parameters were programmed around this. Fuel curves have been made so that when the throttle is open at say 10% it's be programmed that only so much air is going to be introduced to the engine, thus the fuel delivery is adjusted to match. Granted that also relies on the reading from the air flow sensor, so the fuel curve is constantly adjusted regardless depending on how rich or lean the engine is running based on readings from the O2 sensors. But shift points have also been programmed to respond to throttle position (read via that throttle position sensor on the throttle body), and let's say it's programmed that a 15-20% throttle open position (I'm just pulling numbers out of my *** by the way, no idea what these programmed values are exactly...) is usually while simply cruising, so it's going to try and shift up to a higher gear. When you modify and open up the throttle body and allow it to get more air and rev the engine up quicker at a lower throttle open position, a 15-20% throttle opening turns into an acceleration and not a cruising throttle position, but the computer is still going to shift up and make the trans shift earlier than it's suppose. Obviously not an issue with a manual transmission... But with an automatic it's VERY noticeable, at least if you actually pay attention to the way you're vehicle drives and shifts gears.

The throttle blade modification SHOULD in theory give better gas mileage by opening up the throttle body airflow a little, and I'm not arguing about it giving better immediate throttle response because I agree that it does, but without reconfiguring and reprogramming the on board computer the vehicle just doesn't operate correctly...

 

Hi, I haven`t been here for while.But my question is since my blazer never came with front tow hooks on it.Will it be a problem installing a pair.?It does have the front fog lights opening on it, but do not have any intentions on installing fog lights at all.i`m looking at a used pair of tow hooks on ebay.I just want to make sure I can install the hooks ,without any problems beforeI buy them.Also what`s the procedure on installing both hooks?


Thanks for your time!!

 

Just bake surr ya have the 2 bolt holes on either side in the frme for it and the bolts for it

 

There is a plastic tube coming off the valve cover running to the intake is there supposed to be a filter on that?

 

No sir no filter, that is for crankcase ventilation. There is what is called a PCV (positive crankcase ventilation) valve stuck in the rubber grommet in the valve cover and that plastic hose runs from the PCV valve to the intake tube.

 

That plastic tube doesn't have the pcv valve on it it just goes into the valve cover the pcv is on the driver side and the tube is on the passenger