M1 5w-30 4,613 mi

[rgnar]

Hello,
I have 118,145 mi on a 2004 Honda Accord 2.4L I4. It has been getting 15-23 mpg, and loss of power for the last few months. It used to get 25-30 mpg. I've kept the maintenance schedule.
UOA has 52 ppm Na.
Blackstone thinks I should try another oil?
Could I have a small head gasket leak? Blackstone says M1 doesn't have Na. I only use Honda antifreeze, maybe the Honda antifreeze doesn't have Phosphorus that you would see with Na in a coolant leak, and thus I would only see Na?
Any ideas? Could 5w30 have ruined my mileage?
Code:


OIL M1 5w30 MC5K5w20

MILES IN USE 4.6k 6.5k

MILES 91.5k 118.1k

SAMPLE TAKEN 9/26/13 8/11/11



ALUMINUM 3 5

CHROMIUM 1 1

IRON 15 10

COPPER 1 1

LEAD 3 4

TIN 1 0

MOLYBDENUM 87 143

NICKEL 0 1

MANGANESE 0 0

SILVER 0 0

TITANIUM 0 0

POTASSIUM 0 1

BORON 52 34

SILICON 8 12

SODIUM 52 0

CALCIUM 1212 1987

MAGNESIUM 820 13

PHOSPHORUS 750 723

ZINC 918 879

BARIUM 0 0



SUS VIS 210ºF 57.2 51.3

cSt @ 212ºF 9.41 7.67

FLASHPOINT ºF 395 385

FUEL
ANTIFREEZE ? 0.0

WATER 0 0

INSOLUBLES 0.4 0.3

TBN 3.2 1.8

 

[CATERHAM]

Hi rgnar and welcome to BITOG.

Can you post your BlackStone UOA?

 

[rgnar]

I put the Blackstone numbers in the original post above.

 

[Roob]

With such a drastic drop in mpg I would check the 02 sensors. They can get lazy enough to kill mpg but not enough to trigger a cel warning. If you have or know someone with a scanner that shows live testing of them it's a quick test and they aren't expensive to replace.
I would also check and clean the MAF sensor and throttle body, they can gum up causing problems.
Lastly and often overlooked would be tire pressure, that alone can cause your mpg issue.
Hope it gets sorted.

 

[rgnar]

Could I have a small head gasket leak? Blackstone says M1 doesn't have Na. I only use Honda antifreeze, maybe the Honda antifreeze doesn't have Potassium Phosphorus that you would see with Na in a coolant leak, and thus I would only see Na?

 

[rgnar]

I replaced the O2 sensor in front of the catalytic converter, aka the Air Fuel Ratio sensor. It was a DESNO sensor, exactly like the one the car came with. Also replaced all the spark plugs last Summer with NKG iridiums (also exact stock replacements). No check engine light. Also no codes when hooked up to a computer, at a local shop.

 

[ChiTDI]

Wheel bearing going bad will drop your mileage like a stone as well as the o2 sensors previously mentioned. Check the ATF too, something is causing a lot of resistance.

 

[Rolla07]

A 10 mpg difference??? All of a sudden?

 

[rgnar]

The car doesn't pull to one side or the other. The car is a manual with Redline MTL, changed every 30k. When the car was a about a year old it averaged 33 mpg on a trip from North Carolina to Idaho, with the A/C on and non-conservative driving. I've had similar fuel economy on other cross country trips since. Around town I would get 25 mpg. Now it gets 20-23 mpg on the highway, and has got as bad as 15 mpg.

 

[ChiTDI]

I'd look closely at all your vacuum connections as well.

 

[Clevy]

Originally Posted By: rgnar
Hello,
I have 118,145 mi on a 2004 Honda Accord 2.4L I4. It has been getting 15-23 mpg, and loss of power for the last few months. It used to get 25-30 mpg. I've kept the maintenance schedule.
UOA has 52 ppm Na.
Blackstone thinks I should try another oil?
Could I have a small head gasket leak? Blackstone says M1 doesn't have Na. I only use Honda antifreeze, maybe the Honda antifreeze doesn't have Phosphorus that you would see with Na in a coolant leak, and thus I would only see Na?
Any ideas? Could 5w30 have ruined my mileage?
Code:


OIL M1 5w30 MC5K5w20

MILES IN USE 4.6k 6.5k

MILES 91.5k 118.1k

SAMPLE TAKEN 9/26/13 8/11/11



ALUMINUM 3 5

CHROMIUM 1 1

IRON 15 10

COPPER 1 1

LEAD 3 4

TIN 1 0

MOLYBDENUM 87 143

NICKEL 0 1

MANGANESE 0 0

SILVER 0 0

TITANIUM 0 0

POTASSIUM 0 1

BORON 52 34

SILICON 8 12

SODIUM 52 0

CALCIUM 1212 1987

MAGNESIUM 820 13

PHOSPHORUS 750 723

ZINC 918 879

BARIUM 0 0



SUS VIS 210ºF 57.2 51.3

cSt @ 212ºF 9.41 7.67

FLASHPOINT ºF 395 385

FUEL
ANTIFREEZE ? 0.0

WATER 0 0

INSOLUBLES 0.4 0.3

TBN 3.2 1.8



My RT charger gets better mileage than your car does. Take it in and get whatever it is fixed. Fixing it will pay for itself

 

[rgnar]

Clevy,
I've taken it in a few times to a good mechanic. First talked to me about using the AC and it dropping my fuel economy. As if I hadn't used the AC during my previous 10 years of owning the car.
Then they took the car for a day plugged it into the computer and got no engine codes.
This car has been awesome for 10 years and now it is kind of on the skids. It has to be something simple.

 

[Finz]

This just started over the last few months...? Did It drop suddenly or was it a progression?

Driving patterns the same?

Do you notice rough starting or idle?

Start with the basics:

Get a bottle of Techron in there to clean the injectors
Pull the plugs and examine
Replace PCV and hoses (you may have mentioned this was already done?)
Does the oil look contaminated with coolant?
Start using a UCL (TC-W3, MMO, Lucas,...)
Check air filter

I can't see how a coolant leak could have such an impact. Something so sudden and with such an impact...?

How are the brakes? Possible the calipers are not fully releasing and causing drag (happened on my son's '04 Civic - rear driver side was hanging up... Greased the pins and problem fixed)

I have an 05 Accord and have been using M1 0W-20... Just curious as to why you use a 30 ?

 

[mwball0]

Go get a professional fuel system cleaning done. Dirty injectors and valves will zap your fuel economy like crazy. If you have them in your area try Valvoline, they have a money back guarantee! If it doesn't work they refund the cost.

 

[k24a4]

Originally Posted By: Finz
This just started over the last few months...? Did It drop suddenly or was it a progression?

Driving patterns the same?

Do you notice rough starting or idle?

Start with the basics:

Get a bottle of Techron in there to clean the injectors
Pull the plugs and examine
Replace PCV and hoses (you may have mentioned this was already done?)
Does the oil look contaminated with coolant?
Start using a UCL (TC-W3, MMO, Lucas,...)
Check air filter

I can't see how a coolant leak could have such an impact. Something so sudden and with such an impact...?

How are the brakes? Possible the calipers are not fully releasing and causing drag (happened on my son's '04 Civic - rear driver side was hanging up... Greased the pins and problem fixed)

I have an 05 Accord and have been using M1 0W-20... Just curious as to why you use a 30 ?





This ^^. I was going to mention the pcv and brakes but Finz beat me to it. PCV is an easy DIY recommended every 60k or so. $20 part, 5 minutes to replace. Coast at varying speeds, is there more resistance than usual? Could be the brakes, frozen caliper, locked parking brake, etc.

Like previously mentioned, how does it idle? If rough or sluggish, could be a coil pack.

In any event you are smart to track your mpg and notice the problem in the first place. That is half the battle. Let us know how it goes.

 

[bigt61]

Catalytic converter getting plugged? That will kill power and mileage. What is the warm idle speed in neutral?