god awful fuel economy grand prix gxp
#83
is there anyway to get some better mpg out of these ls4's i have a gxp 06 and the wife drives it mostly and it usualy displays 18's for avg mpg and that's alot of hyw driving mostly took it on a trip and the wind helped me achive 27.4 on the way home the wind wasn't so kind. is there a way to keep the dod enabled longer or allow it to engage sooner or something. I was thinking about doing a cold air kit and a magnaflow system not sure if that will help at all probably should check the plugs and o2's just haven't had time yet
#84
With 4 cylinder mode my overally average was 18.7..
With it off its 17.9.....The drop is definitely worth it.
There is no way to enable DOD to stay on longer...Well I think you can change when it enables but you would need a Tuner to do so..The stock setting already enables it for when 4 cylinder would be more efficient...I think the only way you could get more is if you put on the Diablosport DOD tune...Ive never used it so I cant speak for it however..
With it off its 17.9.....The drop is definitely worth it.
There is no way to enable DOD to stay on longer...Well I think you can change when it enables but you would need a Tuner to do so..The stock setting already enables it for when 4 cylinder would be more efficient...I think the only way you could get more is if you put on the Diablosport DOD tune...Ive never used it so I cant speak for it however..
#85
Hey guys,
I have read all the stuff about bad MPG but I have a 2007 GXP and I'm getting 25 when I drive easy and 23 N-change when I'm giving it the throttle hard(AVG numbers). When I check my odometer to fuel I put in the math is almost dead nuts. I no mods just a K&N panel in the air box (that's not a mod to me). I live in MI so I have good air but what gives with these other cars???
I have read all the stuff about bad MPG but I have a 2007 GXP and I'm getting 25 when I drive easy and 23 N-change when I'm giving it the throttle hard(AVG numbers). When I check my odometer to fuel I put in the math is almost dead nuts. I no mods just a K&N panel in the air box (that's not a mod to me). I live in MI so I have good air but what gives with these other cars???
#86
Too many variables... What day of the week it was built on, what oil you use, maintenance records, driving style, weight, tire inflation, red lights, road conditions, weather, etc...
No way to directly compare mileage... And the EPA estimates suck so they are barely a basis for comparison. I think the only consensus that we might even be remotely close to coming to is... "If you are worried about MPGs do not buy a V8."
John
No way to directly compare mileage... And the EPA estimates suck so they are barely a basis for comparison. I think the only consensus that we might even be remotely close to coming to is... "If you are worried about MPGs do not buy a V8."
John
#87
There is no way to enable DOD to stay on longer...Well I think you can change when it enables but you would need a Tuner to do so..The stock setting already enables it for when 4 cylinder would be more efficient...I think the only way you could get more is if you put on the Diablosport DOD tune...Ive never used it so I cant speak for it however..
I can tell it to stay on longer, when it's allowed to come on, etc etc...
__________________
06MonteSS / DiabLew Tune
2014 Camaro 2SS/RS - LS3, 6-speed manual, short-throw performance shifter, NPP dual-mode performance exhaust, 1LE front splitter, ZL1 rockers, Z28 Rear Spoiler, all paint-matched Red Rock Metallic, BMR strut tower brace, Cold Air Inductions cold air intake, Apex Motorsports, Inc. catch-can, Custom DiabLew Tune
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com
06MonteSS / DiabLew Tune
2014 Camaro 2SS/RS - LS3, 6-speed manual, short-throw performance shifter, NPP dual-mode performance exhaust, 1LE front splitter, ZL1 rockers, Z28 Rear Spoiler, all paint-matched Red Rock Metallic, BMR strut tower brace, Cold Air Inductions cold air intake, Apex Motorsports, Inc. catch-can, Custom DiabLew Tune
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com
#89
I made a topic awhile back about getting bad fuel mileage. I was averaging 12.6 to 14.8. I changed my driving style very simply and have been getting 16.0 to 17.2 ever since.
In 30 to 40 mph zones, accelerate moderately in 1st to ~15, 2nd to ~25, and stay in 3rd unless you're going faster than 40 to 45 mph. Once in 3rd you can accelerate slowly and the DOD or AFM will come on and put the car in 4 cylinder mode.
I was using 4th assuming that if the car would go into overdrive, I'd be better off. Well, I wasn't. I was burning more fuel to maintain 35 mph in 4th than I was in 3rd. So don't use 4th unless you're going highway speeds.
In 30 to 40 mph zones, accelerate moderately in 1st to ~15, 2nd to ~25, and stay in 3rd unless you're going faster than 40 to 45 mph. Once in 3rd you can accelerate slowly and the DOD or AFM will come on and put the car in 4 cylinder mode.
I was using 4th assuming that if the car would go into overdrive, I'd be better off. Well, I wasn't. I was burning more fuel to maintain 35 mph in 4th than I was in 3rd. So don't use 4th unless you're going highway speeds.
#90
I own a 2008 gp gxp. I used to get about 320 miles per tank. I am lucky to get 180 now. I have replaced everything conceivable to gain the previous mpg's and have had no success. New plugs and wires, new o2 sensors, new maf sensor and reverted to stock air filter box. Nothing has made any bit of difference. I am thinking that i may need to get the timing adjusted. I am at my wits end here. Any help would be appreciated. 11.8 mpg is just haunting my wallet. From 320 miles to 180 per tank is just not normal. What is the most perplexing of it all is that there are no codes being thrown at all. I watched the mpgs go down progressively over the past 6 months. Shall i just overhaul the motor or what?? I drive it extremely hard. Maybe it's just had it. Time for a new motor is all i can think at this point.
#91
How many miles on the car? Are you seeing any oil consumption? Driving habits change?
Timing doesn't "go out" on a modern motor, as it is computer controlled, so you can eliminate that. If your timing chain was badly stretched, you'd be throwing cam and/or crank position sensor codes, so I don't think it's that.
We need a bit more info to help with a diagnosis, though.
Timing doesn't "go out" on a modern motor, as it is computer controlled, so you can eliminate that. If your timing chain was badly stretched, you'd be throwing cam and/or crank position sensor codes, so I don't think it's that.
We need a bit more info to help with a diagnosis, though.
#92
how many miles on the car? Are you seeing any oil consumption? Driving habits change?
Timing doesn't "go out" on a modern motor, as it is computer controlled, so you can eliminate that. If your timing chain was badly stretched, you'd be throwing cam and/or crank position sensor codes, so i don't think it's that.
We need a bit more info to help with a diagnosis, though.
Timing doesn't "go out" on a modern motor, as it is computer controlled, so you can eliminate that. If your timing chain was badly stretched, you'd be throwing cam and/or crank position sensor codes, so i don't think it's that.
We need a bit more info to help with a diagnosis, though.
Last edited by GXP303; 07-24-2013 at 09:32 AM.
#94
__________________
ATI ProCharger and Moser Sales 260 672-2076
PM's disabled, please e-mail me
E-mail: brutespeed@gmail.comob@brutespeed.com
https://brutespeed.com/ Link to website
ATI ProCharger and Moser Sales 260 672-2076
PM's disabled, please e-mail me
E-mail: brutespeed@gmail.comob@brutespeed.com
https://brutespeed.com/ Link to website
#97
It's worse now. My information center says that I am getting 8.7 mpg or 150 miles per tank. I am just going to bite the bullet and take her in to the dealer and leave all my limbs as payment. Just as long as she's back to where she should be. Thank you for your replies and suggestions.
#99
MPG Concern on '06 GXP
I am a new owner of an '06 GXP which has right at about 30k miles on it. I expected to get at least about 20MPG or was hoping for a little better if possible. Most of my driving is highway and I'll admit that when I first got the car I had my foot in it more than usual. (LOVE the sound of that V8 lol) However since then I have tried to not drive quite so aggressively and I'm STILL getting right around 16MPG.
I was reading that these motors came with DoD as an "option" but have no way to know if mine has it or if they all did actually come with it. Any ideas on what I might check to see what could be causing this crappy mileage would be great.
Little info on the car, It was garage kept without a scratch on it and had 28k miles on it when I bought it. When I first got it I ran some injector cleaner thru it and have tried running it with both 87 and 93 octane fuel with the same results. I haven't had the chance to check the air filter yet but I don't know how much difference it might make.....plus it's not like it's got 80k miles on it anyway.
Thanks in advance for any help on this.
I was reading that these motors came with DoD as an "option" but have no way to know if mine has it or if they all did actually come with it. Any ideas on what I might check to see what could be causing this crappy mileage would be great.
Little info on the car, It was garage kept without a scratch on it and had 28k miles on it when I bought it. When I first got it I ran some injector cleaner thru it and have tried running it with both 87 and 93 octane fuel with the same results. I haven't had the chance to check the air filter yet but I don't know how much difference it might make.....plus it's not like it's got 80k miles on it anyway.
Thanks in advance for any help on this.
#100
I am a new owner of an '06 GXP which has right at about 30k miles on it. I expected to get at least about 20MPG or was hoping for a little better if possible. Most of my driving is highway and I'll admit that when I first got the car I had my foot in it more than usual. (LOVE the sound of that V8 lol) However since then I have tried to not drive quite so aggressively and I'm STILL getting right around 16MPG.
I was reading that these motors came with DoD as an "option" but have no way to know if mine has it or if they all did actually come with it. Any ideas on what I might check to see what could be causing this crappy mileage would be great.
Little info on the car, It was garage kept without a scratch on it and had 28k miles on it when I bought it. When I first got it I ran some injector cleaner thru it and have tried running it with both 87 and 93 octane fuel with the same results. I haven't had the chance to check the air filter yet but I don't know how much difference it might make.....plus it's not like it's got 80k miles on it anyway.
Thanks in advance for any help on this.
I was reading that these motors came with DoD as an "option" but have no way to know if mine has it or if they all did actually come with it. Any ideas on what I might check to see what could be causing this crappy mileage would be great.
Little info on the car, It was garage kept without a scratch on it and had 28k miles on it when I bought it. When I first got it I ran some injector cleaner thru it and have tried running it with both 87 and 93 octane fuel with the same results. I haven't had the chance to check the air filter yet but I don't know how much difference it might make.....plus it's not like it's got 80k miles on it anyway.
Thanks in advance for any help on this.
I'd replace the front 02 sensor and see if that helps out the fuel mileage. Bob
__________________
ATI ProCharger and Moser Sales 260 672-2076
PM's disabled, please e-mail me
E-mail: brutespeed@gmail.comob@brutespeed.com
https://brutespeed.com/ Link to website
ATI ProCharger and Moser Sales 260 672-2076
PM's disabled, please e-mail me
E-mail: brutespeed@gmail.comob@brutespeed.com
https://brutespeed.com/ Link to website