Car feels sluggish when fuel tank is less than half
02-05-2018, 08:50 AM
#1
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Car feels sluggish when fuel tank is less than half
Hello everyone, this is my first post so I apologize if I posted in wrong place.
I bought a 2008 TL Auto w/ nav with 127k miles around a month ago.
From the past three fuel fill-ups (shell v-power), I noticed that the car feels sluggish when fuel is less than half tank. Once I top up, the car drives excellent and the acceleration is back to normal. I don't know if the problem was already there when I bought the car. Does anyone know what might be the problem? Thanks!
I bought a 2008 TL Auto w/ nav with 127k miles around a month ago.
From the past three fuel fill-ups (shell v-power), I noticed that the car feels sluggish when fuel is less than half tank. Once I top up, the car drives excellent and the acceleration is back to normal. I don't know if the problem was already there when I bought the car. Does anyone know what might be the problem? Thanks!
02-05-2018, 09:09 AM
#6
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I didn't find any problems like this when I searched the thread but I found similar cases in bmw and Subaru forums where they said it might be the fuel pump going bad.
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02-05-2018, 09:24 AM
#9
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Okay. Every flat road feels like going over steep hill.
Most of the times, I feel this while cruising at city speeds. RPM range is around 1500 - 2500.
I can maintain 35, 45 and 55 mph but it's not as smooth when compared to driving the car with more than half tank. I can maintain those speeds but I have to give it more gas. It feels like it is hesitating to go.
Whenever I fill up, the car runs significantly smoother.
This is the best I can do to explain my situation.
Most of the times, I feel this while cruising at city speeds. RPM range is around 1500 - 2500.
I can maintain 35, 45 and 55 mph but it's not as smooth when compared to driving the car with more than half tank. I can maintain those speeds but I have to give it more gas. It feels like it is hesitating to go.
Whenever I fill up, the car runs significantly smoother.
This is the best I can do to explain my situation.
02-05-2018, 09:30 AM
#10
Maintaining a constant speed with the RPM range in the 1200-2000 range, will require you to push the pedal to get the RPMs higher in the rev range.
at 4000-5000 RPM, the camshaft switches to a higher profile called vtec. We make the most power above 5000 RPM.
It still doesn't sound like anything is wrong with your car
at 4000-5000 RPM, the camshaft switches to a higher profile called vtec. We make the most power above 5000 RPM.
It still doesn't sound like anything is wrong with your car
02-05-2018, 09:36 AM
#11
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I know it doesn't sound like anything wrong. It might be in my mind. But its just that the car feels much more responsive to every slight change when pressing the gas pedal when I top up the fuel.
02-05-2018, 09:59 AM
#13
Racer
you might try reseting the ecu. There's a thread on here somewhere about it. Or disconnect the battery for a little while, but make sure you have your radio and nav codes. See if that makes a difference to start.
02-05-2018, 10:07 AM
#15
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02-05-2018, 10:14 AM
#16
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I read about fuel additives. When I got the car, I tried seafoam in gas tank but it made no difference to the car and at that time, I was not aware of this issue. But when I noticed this, I tried chevron techron and it made my car noticeably smoother but didn't resolve my issue.
I never tried B12 so I will give that a try. Thanks!
I never tried B12 so I will give that a try. Thanks!
02-05-2018, 10:23 AM
#18
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Fuel additives generally work about as well as adding l'huile de serpent to one's gas tank. In this instance there is about a zero percent chance of them working as the car apparently runs well with at least a half-tank of fuel; said another way, there is something physically wrong with the fuel system.
My guess would be something to do with either the evap system or the fuel pump.
My guess would be something to do with either the evap system or the fuel pump.
02-05-2018, 10:23 AM
#19
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Alright. I will do that once I get the chance. Right now, I have full tank and car is running perfectly. Once I get to that fuel level I will record a video.
02-05-2018, 10:25 AM
#20
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Fuel additives generally work about as well as adding l'huile de serpent to one's gas tank. In this instance there is about a zero percent chance of them working as the car apparently runs well with at least a half-tank of fuel; said another way, there is something physically wrong with the fuel system.
My guess would be something to do with either the evap system or the fuel pump.
My guess would be something to do with either the evap system or the fuel pump.
well my guess is that it's in his mind anyway so what's another snake oil mind trick to counteract the other mind trick...
think about it
02-05-2018, 05:20 PM
#21
Maybe we can at least prove it's not all in your head.
02-05-2018, 05:27 PM
#22
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In fact, I am planning to visit Columbus sometime within the next month.
I will PM you about it. Thanks!
02-07-2018, 11:59 AM
#24
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Hey all, I need help with one more thing.
My driver's side rear tire is Michelin Pilot Sport A/S 3+ of the size 225/45/ZR17 but the rest are Primacy MXM4 235/45/R17. All of the tires have 25000 miles on them.
I am getting vibrations after 60 mph and it gets worse as the speed increases.
I have narrowed my choices down to two tires:
1) Nitto Motivos - 245/45/17 - $803
2) Pirelli P7 Cinturato A/S+ - 245/45/17 - $880 but this includes road force balancing.
I also noticed from the CarFax that the previous owner didn't do the timing belt service and my car is at almost 130k miles.
The price of TB service with Aisin kit is around $930 with 2 years/24k warranty.
Which one do you think I should do first? as I don't have the budget to do both.
My driver's side rear tire is Michelin Pilot Sport A/S 3+ of the size 225/45/ZR17 but the rest are Primacy MXM4 235/45/R17. All of the tires have 25000 miles on them.
I am getting vibrations after 60 mph and it gets worse as the speed increases.
I have narrowed my choices down to two tires:
1) Nitto Motivos - 245/45/17 - $803
2) Pirelli P7 Cinturato A/S+ - 245/45/17 - $880 but this includes road force balancing.
I also noticed from the CarFax that the previous owner didn't do the timing belt service and my car is at almost 130k miles.
The price of TB service with Aisin kit is around $930 with 2 years/24k warranty.
Which one do you think I should do first? as I don't have the budget to do both.
02-07-2018, 12:14 PM
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02-07-2018, 12:59 PM
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Hey all, I need help with one more thing.
My driver's side rear tire is Michelin Pilot Sport A/S 3+ of the size 225/45/ZR17 but the rest are Primacy MXM4 235/45/R17. All of the tires have 25000 miles on them.
I am getting vibrations after 60 mph and it gets worse as the speed increases.
I have narrowed my choices down to two tires:
1) Nitto Motivos - 245/45/17 - $803
2) Pirelli P7 Cinturato A/S+ - 245/45/17 - $880 but this includes road force balancing.
My driver's side rear tire is Michelin Pilot Sport A/S 3+ of the size 225/45/ZR17 but the rest are Primacy MXM4 235/45/R17. All of the tires have 25000 miles on them.
I am getting vibrations after 60 mph and it gets worse as the speed increases.
I have narrowed my choices down to two tires:
1) Nitto Motivos - 245/45/17 - $803
2) Pirelli P7 Cinturato A/S+ - 245/45/17 - $880 but this includes road force balancing.
02-07-2018, 04:32 PM
#28
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Also, do you have any idea which would be better... Nitto or Pirelli? I don't race but I drive aggressively and I do a lot of long trips.
02-07-2018, 05:25 PM
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I'm going with the Pirelli tires on my TL; my wife's former GTI had a tendency to cause some tires to get noisy (you know, "whup-whup-whup..." drone, the Comp2 A/Ss on my TL do that as well); the Cinturato P7s had 30,000+ miles on them when we traded it in and they were still very quiet.
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02-08-2018, 08:43 PM
#31
02-08-2018, 09:47 PM
#32
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02-08-2018, 09:52 PM
#33
02-08-2018, 09:56 PM
#34
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I hope the TL's sluggishness problem will be solved after this and I get my mileage back. I am only getting 13 mpg at present.
02-10-2018, 07:48 PM
#36
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Update: Replaced the O2 sensor and I am happy to say the car picks up speed as it should. The sluggishness is gone.
Now, I just have to find what's causing vibration on gas pedal while accelerating. Can it be the axles?
I have changed the two transmission mounts and front and side engine mounts. But the engine mounts are aftermarket so there is lot of play in the engine. I guess that is why there is strong front end vibration while idling which also vibrates my headrests and steering wheel. So do you think motor mounts would cause vibration in gas pedal?
Now, I just have to find what's causing vibration on gas pedal while accelerating. Can it be the axles?
I have changed the two transmission mounts and front and side engine mounts. But the engine mounts are aftermarket so there is lot of play in the engine. I guess that is why there is strong front end vibration while idling which also vibrates my headrests and steering wheel. So do you think motor mounts would cause vibration in gas pedal?
02-10-2018, 09:34 PM
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Could very well be the axles.
02-13-2018, 10:20 AM
#38
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rear engine mount is the most important in preventing transfer of engine room vibrations into the cabin. Why don't you do that one?
02-13-2018, 01:54 PM
#39
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02-14-2018, 06:29 PM
#40
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