I'm also with the camp that it's not the oil. Sluggishness and loss of MPG sounds more like the engine needs a good look over. Healthy engines don't care all that much about oil grade, unless something few grades heavier, not thinner is used.
Wrong oil killing mpg on my TSX?
- Thread starter Dohc98vteC
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Originally Posted By: Dohc98vteC
Just about to hit 130k...I realize the winter blend gas etc but I have had the car for 5 years now and it just seems worse. I need to check my tires again too I just remembered I have one a little low. Also, with remote start I am letting the car run 5 minutes or so before I get in so maybe it all makes sense now...
Need to get that summer air out!
Change the air for winter.
Just about to hit 130k...I realize the winter blend gas etc but I have had the car for 5 years now and it just seems worse. I need to check my tires again too I just remembered I have one a little low. Also, with remote start I am letting the car run 5 minutes or so before I get in so maybe it all makes sense now...
Need to get that summer air out!
Change the air for winter.
All of our cars are getting the worst MPH that I can remember. MY wifes Lexus got 13 mpg. My daughter even called last night to say hello. In the conversation, she mentiond that she's getting the worst MPG EVER! And her car usually get great MPG even in the winter. Never below 25 mpg city, winter for the last 4+ years. She got ~ 18+ mpg. I'll check my MPG when I fill up this weekend.
The oil chart for your car only states 5w30 as the recommended oil. Maybe it's been back specced lately? Any idea what make of oil they put in? Bear in mind that it could also be as simple as a bad tank of gas.
Depending on the condition of your engine I'd stick with what's recommended and worked for you with a few changes.
For now, leave the 0w20 in, get all four tires to the correct air pressure, replace the kn air filter with a stock filter(the oil will foul the maf sensor and cause buildup in the intake and throttle body valve causing a bad seal.) Kn filters also flow more air and that requires more fuel. Clean the maf sensor with maf sensor cleaner so you don't damage it.
Drive for a tank or two once this is done and you should see a difference.
If you don't then its time to get your 02 sensors checked with a live scanner. If you don't have any codes showing now, you could have one that's lazy enough to harm mpg but it's not far enough out of spec to throw a code.
Depending on the condition of your engine I'd stick with what's recommended and worked for you with a few changes.
For now, leave the 0w20 in, get all four tires to the correct air pressure, replace the kn air filter with a stock filter(the oil will foul the maf sensor and cause buildup in the intake and throttle body valve causing a bad seal.) Kn filters also flow more air and that requires more fuel. Clean the maf sensor with maf sensor cleaner so you don't damage it.
Drive for a tank or two once this is done and you should see a difference.
If you don't then its time to get your 02 sensors checked with a live scanner. If you don't have any codes showing now, you could have one that's lazy enough to harm mpg but it's not far enough out of spec to throw a code.
With the extreme cold lately, checking tire pressure daily should be a priority. Low tire pressure will kill mpg no matter what season it is.
Originally Posted By: Gokhan
Originally Posted By: Dohc98vteC
I am getting horrible mileage even for winter standards here. The only thing different is my dealer insisting on using 5w-20 or 0w-20 oil, instead of 5w30 based on the Acura oil chart they have at the service dept. But the thing is for 2004 only 5w30 is specified, not sure why same model same engine TSX would show 0w-20 and 5w-20. The car feels real sluggish too like performance is suffering. Bottom line, with temps here at well below 0 some nights, should I switch back to 5w30?
Technically, yes, thinner oil could reduce MPG.
Thinner oil increases frictional loss in the valvetrain.
Thinner oil tends to decrease frictional loss in the bearings.
Thinner oil may increase or decrease the frictional loss in the cylinders.
Again, thinner oil always causes more fricton in the valvetrain. However, bearings and (most parts of the) cylinders are hydrodynamically lubricated and unless there is oil-film breakdown due to thinner oil, friction will be reduced. If there is oil-film breakdown due to thinner oil, hydrodynamic lubrication will fail and you will have more friction thanks to metal-to-metal contact like in the valvetrain.
So, yes, in principle, there is an optimum viscosity for highest MPG for a given engine. You can't go arbitrarily thin (0W-16, 0W-10, etc.) and hope that your MPG will keep increasing.
Also, different oils with give different MPG for the same SAE viscosity grade because of different friction modifiers and different base oil (synthetic gives better MPG).
All this said, I doubt that your loss of MPG is oil-related but I think you are more likely having some other maintenance or tune-up problems. Dealer might have messed up something else. Also, it's winter and MPG usually drops in the winter.
Thinner oils cause more friction in the valve train? Really?
Originally Posted By: Dohc98vteC
I am getting horrible mileage even for winter standards here. The only thing different is my dealer insisting on using 5w-20 or 0w-20 oil, instead of 5w30 based on the Acura oil chart they have at the service dept. But the thing is for 2004 only 5w30 is specified, not sure why same model same engine TSX would show 0w-20 and 5w-20. The car feels real sluggish too like performance is suffering. Bottom line, with temps here at well below 0 some nights, should I switch back to 5w30?
Technically, yes, thinner oil could reduce MPG.
Thinner oil increases frictional loss in the valvetrain.
Thinner oil tends to decrease frictional loss in the bearings.
Thinner oil may increase or decrease the frictional loss in the cylinders.
Again, thinner oil always causes more fricton in the valvetrain. However, bearings and (most parts of the) cylinders are hydrodynamically lubricated and unless there is oil-film breakdown due to thinner oil, friction will be reduced. If there is oil-film breakdown due to thinner oil, hydrodynamic lubrication will fail and you will have more friction thanks to metal-to-metal contact like in the valvetrain.
So, yes, in principle, there is an optimum viscosity for highest MPG for a given engine. You can't go arbitrarily thin (0W-16, 0W-10, etc.) and hope that your MPG will keep increasing.
Also, different oils with give different MPG for the same SAE viscosity grade because of different friction modifiers and different base oil (synthetic gives better MPG).
All this said, I doubt that your loss of MPG is oil-related but I think you are more likely having some other maintenance or tune-up problems. Dealer might have messed up something else. Also, it's winter and MPG usually drops in the winter.
Thinner oils cause more friction in the valve train? Really?
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Both of my vehicles have been horrible gas mileage this winter.
The last few tanks on the Cherokee have been a solid 10MPG.Luckily, I have only been driving it to work once every other week.
the focus is averaging around 30. Last winter it was 32.
Tires pumped up to 44 on the winterfarce tires - apparently anything lower and they only wear the edges.
Originally Posted By: tig1
Originally Posted By: Gokhan
Originally Posted By: Dohc98vteC
I am getting horrible mileage even for winter standards here. The only thing different is my dealer insisting on using 5w-20 or 0w-20 oil, instead of 5w30 based on the Acura oil chart they have at the service dept. But the thing is for 2004 only 5w30 is specified, not sure why same model same engine TSX would show 0w-20 and 5w-20. The car feels real sluggish too like performance is suffering. Bottom line, with temps here at well below 0 some nights, should I switch back to 5w30?
Technically, yes, thinner oil could reduce MPG.
Thinner oil increases frictional loss in the valvetrain.
Thinner oil tends to decrease frictional loss in the bearings.
Thinner oil may increase or decrease the frictional loss in the cylinders.
Again, thinner oil always causes more fricton in the valvetrain. However, bearings and (most parts of the) cylinders are hydrodynamically lubricated and unless there is oil-film breakdown due to thinner oil, friction will be reduced. If there is oil-film breakdown due to thinner oil, hydrodynamic lubrication will fail and you will have more friction thanks to metal-to-metal contact like in the valvetrain.
So, yes, in principle, there is an optimum viscosity for highest MPG for a given engine. You can't go arbitrarily thin (0W-16, 0W-10, etc.) and hope that your MPG will keep increasing.
Also, different oils with give different MPG for the same SAE viscosity grade because of different friction modifiers and different base oil (synthetic gives better MPG).
All this said, I doubt that your loss of MPG is oil-related but I think you are more likely having some other maintenance or tune-up problems. Dealer might have messed up something else. Also, it's winter and MPG usually drops in the winter.
Thinner oils cause more friction in the valve train? Really?
BRB ... I'm going to dump the Mobil 1 0w-20 out of my Focus and dump in some 20w-50. The gas mileage, especially in these cold temps, should shoot right up!
The last few tanks on the Cherokee have been a solid 10MPG.Luckily, I have only been driving it to work once every other week.
the focus is averaging around 30. Last winter it was 32.
Tires pumped up to 44 on the winterfarce tires - apparently anything lower and they only wear the edges.
Originally Posted By: tig1
Originally Posted By: Gokhan
Originally Posted By: Dohc98vteC
I am getting horrible mileage even for winter standards here. The only thing different is my dealer insisting on using 5w-20 or 0w-20 oil, instead of 5w30 based on the Acura oil chart they have at the service dept. But the thing is for 2004 only 5w30 is specified, not sure why same model same engine TSX would show 0w-20 and 5w-20. The car feels real sluggish too like performance is suffering. Bottom line, with temps here at well below 0 some nights, should I switch back to 5w30?
Technically, yes, thinner oil could reduce MPG.
Thinner oil increases frictional loss in the valvetrain.
Thinner oil tends to decrease frictional loss in the bearings.
Thinner oil may increase or decrease the frictional loss in the cylinders.
Again, thinner oil always causes more fricton in the valvetrain. However, bearings and (most parts of the) cylinders are hydrodynamically lubricated and unless there is oil-film breakdown due to thinner oil, friction will be reduced. If there is oil-film breakdown due to thinner oil, hydrodynamic lubrication will fail and you will have more friction thanks to metal-to-metal contact like in the valvetrain.
So, yes, in principle, there is an optimum viscosity for highest MPG for a given engine. You can't go arbitrarily thin (0W-16, 0W-10, etc.) and hope that your MPG will keep increasing.
Also, different oils with give different MPG for the same SAE viscosity grade because of different friction modifiers and different base oil (synthetic gives better MPG).
All this said, I doubt that your loss of MPG is oil-related but I think you are more likely having some other maintenance or tune-up problems. Dealer might have messed up something else. Also, it's winter and MPG usually drops in the winter.
Thinner oils cause more friction in the valve train? Really?
BRB ... I'm going to dump the Mobil 1 0w-20 out of my Focus and dump in some 20w-50. The gas mileage, especially in these cold temps, should shoot right up!
Originally Posted By: tig1
Thinner oils cause more friction in the valve train? Really?
Of course.
Valvetrain works in the boundary-lubrication regime, which means metal-to-metal contact. The thinner the oil, the thinner the oil film is, and the thinner the oil film, there will be more metal-to-metal contact and more friction.
However, usually the frictional loss in the bearings and cylinders dominate the frictional loss in the valvetrain. Since those work in the hydrodynamic-lubrication regime (no metal-to-metal contact), you will get less friction with thinner oil, as the internal friction of the oil will decrease with decreasing viscosity. Note that this is only true if there is no oil-film breakdown. If you go too thin, oil film will breakdown and you will go into boundary-lubrication regime even in the bearings and cylinders.
Here is an excellent review article on the effects of oil on fuel economy by Shell:
Improved fuel efficiency by lubricant design: a review
Thinner oils cause more friction in the valve train? Really?
Of course.
Valvetrain works in the boundary-lubrication regime, which means metal-to-metal contact. The thinner the oil, the thinner the oil film is, and the thinner the oil film, there will be more metal-to-metal contact and more friction.
However, usually the frictional loss in the bearings and cylinders dominate the frictional loss in the valvetrain. Since those work in the hydrodynamic-lubrication regime (no metal-to-metal contact), you will get less friction with thinner oil, as the internal friction of the oil will decrease with decreasing viscosity. Note that this is only true if there is no oil-film breakdown. If you go too thin, oil film will breakdown and you will go into boundary-lubrication regime even in the bearings and cylinders.
Here is an excellent review article on the effects of oil on fuel economy by Shell:
Improved fuel efficiency by lubricant design: a review
The k24 in that model year TSX is very closely related to the one found in the Accord, Element, and CRV of that generation, all of which spec'd 5w-20 and were subsequently back spec'd to 0w-20. I believe 5w30 was the recommended weight because the k24 in the TSX was tuned more for performance.
Like others, I highly doubt the dip in mpg is due to the lower viscosity oil. My average tank has taken a 3-4 mpg hit this year with the combination of Winter blended gas and Arctic temps.
BTW, love the first gen TSX. Could not afford one at the time I bought the Accord, but would certainly consider one used now.
Like others, I highly doubt the dip in mpg is due to the lower viscosity oil. My average tank has taken a 3-4 mpg hit this year with the combination of Winter blended gas and Arctic temps.
BTW, love the first gen TSX. Could not afford one at the time I bought the Accord, but would certainly consider one used now.
2004-206 TSX has a real exhaust vtec, the 1G tsx never back spec to the xw20. the latest chart still recommend 5w30.
my tsx has poorest mpg in the cold weather, this winter has been specially cold for my area, mpg on both mdx and tsx have been worse then normal. another thing you may want to look is the bearing or sticking break. here in Toronto, the 91 octane fuel cost 15c/L more then 87 octane, I run regular in winter to minimum the impact on wallet, cant drive fast, and the car idle often in winter anyway.
my tsx has poorest mpg in the cold weather, this winter has been specially cold for my area, mpg on both mdx and tsx have been worse then normal. another thing you may want to look is the bearing or sticking break. here in Toronto, the 91 octane fuel cost 15c/L more then 87 octane, I run regular in winter to minimum the impact on wallet, cant drive fast, and the car idle often in winter anyway.
Originally Posted By: demarpaint
Winter blend fuel and cold are taking their toll here. Cars run rich longer in extreme cold using more fuel, and winter blend gas doesn't help matters much.
I occasionally hit some city traffic for a few minutes in the early morning. With the single-digit temps this season, the smell of un-burnt fuel reminds me of filling stations in the days before vapor-recovery nozzles.
Winter blend fuel and cold are taking their toll here. Cars run rich longer in extreme cold using more fuel, and winter blend gas doesn't help matters much.
I occasionally hit some city traffic for a few minutes in the early morning. With the single-digit temps this season, the smell of un-burnt fuel reminds me of filling stations in the days before vapor-recovery nozzles.
Thanks for all the responses guys, I will swap out my filter with the oem one and clean my throttle body while I am there. Also, I use 93 octane fuel so maybe I should dial back to 91 instead and run some Techron at next refuel...I don't want to use anything less than 91 since the TSX K24 is higher compression.
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Originally Posted By: demarpaint
Winter blend fuel and cold are taking their toll here. Cars run rich longer in extreme cold using more fuel, and winter blend gas doesn't help matters much.
^ This.
Correct me if I'm wrong, but aren't you guys having about the worst/coldest winter ever? I see that MANY all-time records are being broken this year.
It is a fact that gas engines are primarily BTU engines and will loose between 1/2 to 1 mpg for every 10 degrees below 70 degrees the ambient temperature is, and that is AFTER the engine is warmed up. The old-timers used to put cardboard in front of part of the radiator to help keep the engine compartment warmer claiming that it helped warm the engine up quicker and improve MPG a little.
Winter blend fuel and cold are taking their toll here. Cars run rich longer in extreme cold using more fuel, and winter blend gas doesn't help matters much.
^ This.
Correct me if I'm wrong, but aren't you guys having about the worst/coldest winter ever? I see that MANY all-time records are being broken this year.
It is a fact that gas engines are primarily BTU engines and will loose between 1/2 to 1 mpg for every 10 degrees below 70 degrees the ambient temperature is, and that is AFTER the engine is warmed up. The old-timers used to put cardboard in front of part of the radiator to help keep the engine compartment warmer claiming that it helped warm the engine up quicker and improve MPG a little.
Originally Posted By: wag123
Originally Posted By: demarpaint
Winter blend fuel and cold are taking their toll here. Cars run rich longer in extreme cold using more fuel, and winter blend gas doesn't help matters much.
^ This.
Correct me if I'm wrong, but aren't you guys having about the worst/coldest winter ever? I see that MANY all-time records are being broken this year.
It is a fact that gas engines are primarily BTU engines and will loose between 1/2 to 1 mpg for every 10 degrees below 70 degrees the ambient temperature is, and that is AFTER the engine is warmed up. The old-timers used to put cardboard in front of part of the radiator to help keep the engine compartment warmer claiming that it helped warm the engine up quicker and improve MPG a little.
You are correct, sir.
Originally Posted By: demarpaint
Winter blend fuel and cold are taking their toll here. Cars run rich longer in extreme cold using more fuel, and winter blend gas doesn't help matters much.
^ This.
Correct me if I'm wrong, but aren't you guys having about the worst/coldest winter ever? I see that MANY all-time records are being broken this year.
It is a fact that gas engines are primarily BTU engines and will loose between 1/2 to 1 mpg for every 10 degrees below 70 degrees the ambient temperature is, and that is AFTER the engine is warmed up. The old-timers used to put cardboard in front of part of the radiator to help keep the engine compartment warmer claiming that it helped warm the engine up quicker and improve MPG a little.
You are correct, sir.
I'm running 5w30 in my 04 TSX. The mileage has been [censored] but then again it has been the coldest winter in a while.
However I did notice I am getting better mileage after doing the following (grabbed this from another forum). I would make sure the motor is warm before doing this.
Quote:
The Throttle is "Drive By Wire" and adapts to your particular driving
style. Do a TBA Throttle body adaptation.
1. Get in your car, it doesn't matter if you close the door or not.
2. Turn the key to the on (not start) position, the position just before the starter
turns over.
3. Press the gas pedal to the floor with the key in the "on" position.
4. Hold the pedal to the floor for five seconds, then turn the key back
to the "off" position (don't remove the key), then release the gas
pedal.
5. Wait 2 mins. for a full alignment.
6. Drive the car as you always do.
However I did notice I am getting better mileage after doing the following (grabbed this from another forum). I would make sure the motor is warm before doing this.
Quote:
The Throttle is "Drive By Wire" and adapts to your particular driving
style. Do a TBA Throttle body adaptation.
1. Get in your car, it doesn't matter if you close the door or not.
2. Turn the key to the on (not start) position, the position just before the starter
turns over.
3. Press the gas pedal to the floor with the key in the "on" position.
4. Hold the pedal to the floor for five seconds, then turn the key back
to the "off" position (don't remove the key), then release the gas
pedal.
5. Wait 2 mins. for a full alignment.
6. Drive the car as you always do.
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