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Low MPG and lower power/torque?

Messages
62
Likes
13
Location
Irvine
#1
Hi all,

I have 1300 miles on my ST now and I am now feeling like first and second gears are more anemic than they used to be. Somehow, it doesn't feel like there's much torque at all any more in those gears. In all gears, boost now comes in between 2,500 and 3,000 RPM and I'm averaging around 22MPG with mostly city driving.

I know that after a while, people start to get used to the power, but this seems a bit more significant. I've tightened all of the lower boost clamps in case that was the issue, the only one I'm missing is the one right under the air box but I couldn't loosen the clamp screw by hand so I presume it's not that bad.

Any thoughts? Is this normal? I remember the ST being so taut when i first bought it.
 


Messages
157
Likes
18
Location
Ferndale
#2
I've had mine for 14k miles and the only time I felt that power lacked, I had some loose clamps on the boost pipes. Tightening them down did the trick and an extra few psi brought the car back to life. Have any dash lights? Could you have a defective plug? Could be a number of things. Hope you get it sorted out!
 


OP
S
Messages
62
Likes
13
Location
Irvine
Thread Starter #3
So I might also be the only person on this forum without a Cobb AP. I wonder if that has a lot to do with it, because I'd heard the AP removes the torque limiting in gears 1 and 2? I'm not entirely sure if that's true though.

I'll try messing with the clamps again. I'm wondering if really the low MPG is more due to having to stop at 10-15 stoplights on my 7-mile city commute each way to and from work. I watched my MPGs get up to 27.8, but I only averaged 24 across the commute home tonight.
 


Messages
66
Likes
11
Location
BR
#4
Having that many starts from a dead stop in that short of a trip will definitely hurt mileage. 7 miles is really not far enough to get everything to operating temperature where the engine would be at peak efficiency. Case in point: I had a '00 Civic Si years ago and at one point I lived only 4 miles from work. My then roommate and I moved into a new rental that was 9 miles. Before we moved, I was filling up about once every week and a half to 2 weeks. After? Every week and a half to 2 weeks.

Maybe try letting the car warm up for 5 minutes before you drive off. Also, if it's easy/safe to do so, try timing the lights to where you're not starting from a dead stop at every one. Even a roll from 10 mph will take less energy and therefore fuel.
 


OP
S
Messages
62
Likes
13
Location
Irvine
Thread Starter #5
Having that many starts from a dead stop in that short of a trip will definitely hurt mileage. 7 miles is really not far enough to get everything to operating temperature where the engine would be at peak efficiency. Case in point: I had a '00 Civic Si years ago and at one point I lived only 4 miles from work. My then roommate and I moved into a new rental that was 9 miles. Before we moved, I was filling up about once every week and a half to 2 weeks. After? Every week and a half to 2 weeks.

Maybe try letting the car warm up for 5 minutes before you drive off. Also, if it's easy/safe to do so, try timing the lights to where you're not starting from a dead stop at every one. Even a roll from 10 mph will take less energy and therefore fuel.
I'll try letting it warm up tomorrow. I actually underestimated the lights; the minimum number of stop lights is 21.
 


Messages
66
Likes
11
Location
BR
#6
Yeah, a fair amount of those should be synced up. Just learn the timing and adjust your acceleration accordingly. If it doesn't improve, I would definitely recheck your boost clamps (including the one under the airbox. It only takes one loose one) and bring it in if they're all still good.
 


OP
S
Messages
62
Likes
13
Location
Irvine
Thread Starter #7
Unfortunately while they're synced, they're all dependent on whether people are at the signal on the smaller streets. And there usually are. I've been skip-shifting to improve the mileage. Not that I care about only mileage, but it was a perk of this car when I bought it.
 




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