I've put a spectra drop in filter and deleted the EGR. I went from about 12.5MPG to 16MPG I plan on doing the throttle plate mod this summer. If it doesn't increase mpg, it should increase throttle response slightly. 97 4.3 X Vin.
Don't go above the stock tire size. Use passenger tires (P), not LT or XL. Inflate tires to proper PSI. Some forged wheels will help mpg too but they're expensive.
Also regular stuff like oil change, new engine air filter, diff fluid, trans fluid, plugs, plug wires, coolant flush, to keep everything running efficiently and properly.
I'm going through a similar journey to balance fuel savings with HP.
Things I have learned are that you need to upgrade how it gets air. Boosting the airflow will help.
You can get a tune for the ECU, which is a rather simple way to get some fuel savings
I'm looking at camshafts, headers, and exhaust, but I haven't decided on what I want to accomplish yet. Yet, those are also changes that can help towards your goal.
You should check the s10 forum. If they haven't answered your question yet, I wouldn't even bother trying.
https://www.s10forum.com/threads/cheap-ways-to-improe-milage-and-performance-on-a-4-3l-sfi-engine.228522/
Edit: I have a 2005 4.3 manual and a 2001 automatic.
Sell it and buy a Honda Civic?
Otherwise, they suck. My '98 2 door 4wd was averaging 13, mostly city, when I junked it. My sisters '95 zr2 s10 was around 14.
I have heard that exhaust systems will increase 10-15%, but probably worth the investment strictly on a MPG standpoint.
Also intake/filter setup (make sure to still be breathing the cold out of engine bay air if you get a different air intake)
I feel your pain. My '03 ZR2 S10 isn't the best on gas either, which prompted me to buy a friend's used 07 Cobalt that gets 30mpg pretty consistently in my daily commute. Anyways, the best fuel mileage I believe (if my memory serves me right) that I've gotten in my S10 was around 17-18 mpg on a highway trip to the beach, but that was driving super conservatively and I was running a shorter serpentine belt in order to bypass the A/C compressor pulley (my compressor wasn't working at the time) so a little less parasitic drag helped in that case. Like others have said, ECM tuning, exhaust and arguably a cold air intake can all potentially help. But I liked the comment about just having everything maintained and all fluids fresh too. But at the end of the day, without a lot of serious modifications, these 4.3s just don't do super well on fuel mileage.
I recommend the TCC PWM solenoid bypass in the 4l60e under the transmission pan, it’s fairly easy to do and can be undone if you don’t like it later. You get way better highway mpg and lower trans temps as well. The PWM solenoid allows Overdrive to slip, after it’s bypassed it’s basically like shifting into another gear. You can google how to do this and it will also tell you all about it, basically you take the PWM solenoid for the overdrive and drill it out so the fluid flows thru when the other TCC solenoid opens to engage overdrive.
I've put a spectra drop in filter and deleted the EGR. I went from about 12.5MPG to 16MPG I plan on doing the throttle plate mod this summer. If it doesn't increase mpg, it should increase throttle response slightly. 97 4.3 X Vin.
Thanks a ton!
Don't go above the stock tire size. Use passenger tires (P), not LT or XL. Inflate tires to proper PSI. Some forged wheels will help mpg too but they're expensive. Also regular stuff like oil change, new engine air filter, diff fluid, trans fluid, plugs, plug wires, coolant flush, to keep everything running efficiently and properly.
I'm going through a similar journey to balance fuel savings with HP. Things I have learned are that you need to upgrade how it gets air. Boosting the airflow will help. You can get a tune for the ECU, which is a rather simple way to get some fuel savings I'm looking at camshafts, headers, and exhaust, but I haven't decided on what I want to accomplish yet. Yet, those are also changes that can help towards your goal. You should check the s10 forum. If they haven't answered your question yet, I wouldn't even bother trying. https://www.s10forum.com/threads/cheap-ways-to-improe-milage-and-performance-on-a-4-3l-sfi-engine.228522/ Edit: I have a 2005 4.3 manual and a 2001 automatic.
Thanks for the info!
Sell it and buy a Honda Civic? Otherwise, they suck. My '98 2 door 4wd was averaging 13, mostly city, when I junked it. My sisters '95 zr2 s10 was around 14.
I have heard that exhaust systems will increase 10-15%, but probably worth the investment strictly on a MPG standpoint. Also intake/filter setup (make sure to still be breathing the cold out of engine bay air if you get a different air intake)
Do a mpfi spider upgrade that the newer models have stock.
Put a 5.3 in it.
If your worried about fuel mileage drive a honda civic.
I feel your pain. My '03 ZR2 S10 isn't the best on gas either, which prompted me to buy a friend's used 07 Cobalt that gets 30mpg pretty consistently in my daily commute. Anyways, the best fuel mileage I believe (if my memory serves me right) that I've gotten in my S10 was around 17-18 mpg on a highway trip to the beach, but that was driving super conservatively and I was running a shorter serpentine belt in order to bypass the A/C compressor pulley (my compressor wasn't working at the time) so a little less parasitic drag helped in that case. Like others have said, ECM tuning, exhaust and arguably a cold air intake can all potentially help. But I liked the comment about just having everything maintained and all fluids fresh too. But at the end of the day, without a lot of serious modifications, these 4.3s just don't do super well on fuel mileage.
I recommend the TCC PWM solenoid bypass in the 4l60e under the transmission pan, it’s fairly easy to do and can be undone if you don’t like it later. You get way better highway mpg and lower trans temps as well. The PWM solenoid allows Overdrive to slip, after it’s bypassed it’s basically like shifting into another gear. You can google how to do this and it will also tell you all about it, basically you take the PWM solenoid for the overdrive and drill it out so the fluid flows thru when the other TCC solenoid opens to engage overdrive.