What have I missed??
#1
What have I missed??
I have chked the threads and have,
changed spark plugs to NGK platinum,
changed fuel filter
replaced knock sensor
added KN air filter
replaced a very bad pcv valve
use only prem gas
used sea foam in brake booster
currently have auto rx in for a cleaning
cleaned throttle body and IAC valve
tires inflated to 31psi all round
SO why only 24.5 mpg on the highway. Just what could be wrong? I dont have a heavy foot and I read of many of you getting 30 mpg. I am well below the 28 mpg rating. I know for some this is tedius to see again, so ignore it, but for me It is almost a matter of pride. I have done everything I have seen recommended to do and should be in tip top shape. still...........
just cant figure it out
I have about 93,000 miles
changed spark plugs to NGK platinum,
changed fuel filter
replaced knock sensor
added KN air filter
replaced a very bad pcv valve
use only prem gas
used sea foam in brake booster
currently have auto rx in for a cleaning
cleaned throttle body and IAC valve
tires inflated to 31psi all round
SO why only 24.5 mpg on the highway. Just what could be wrong? I dont have a heavy foot and I read of many of you getting 30 mpg. I am well below the 28 mpg rating. I know for some this is tedius to see again, so ignore it, but for me It is almost a matter of pride. I have done everything I have seen recommended to do and should be in tip top shape. still...........
just cant figure it out
I have about 93,000 miles
#2
Originally Posted by seeker51
I have chked the threads and have,
changed spark plugs to NGK platinum,
changed fuel filter
replaced knock sensor
added KN air filter
replaced a very bad pcv valve
use only prem gas
used sea foam in brake booster
currently have auto rx in for a cleaning
cleaned throttle body and IAC valve
tires inflated to 31psi all round
SO why only 24.5 mpg on the highway. Just what could be wrong? I dont have a heavy foot and I read of many of you getting 30 mpg. I am well below the 28 mpg rating. I know for some this is tedius to see again, so ignore it, but for me It is almost a matter of pride. I have done everything I have seen recommended to do and should be in tip top shape. still...........
just cant figure it out
I have about 93.
changed spark plugs to NGK platinum,
changed fuel filter
replaced knock sensor
added KN air filter
replaced a very bad pcv valve
use only prem gas
used sea foam in brake booster
currently have auto rx in for a cleaning
cleaned throttle body and IAC valve
tires inflated to 31psi all round
SO why only 24.5 mpg on the highway. Just what could be wrong? I dont have a heavy foot and I read of many of you getting 30 mpg. I am well below the 28 mpg rating. I know for some this is tedius to see again, so ignore it, but for me It is almost a matter of pride. I have done everything I have seen recommended to do and should be in tip top shape. still...........
just cant figure it out
I have about 93.
#5
Well, its an Auto, I just got it with about 92,000, it has 93,ooo now supposedly oil has been changed religiously although of course you never know. Its a 98 and regular oil, not synthetic. It seems to run well and as I said I think I have changed everything I know of including aligning it, and chking inflation etc to be sure I did my part.
#6
Originally Posted by seeker51
Well, its an Auto, I just got it with about 92,000, it has 93,ooo now supposedly oil has been changed religiously although of course you never know. Its a 98 and regular oil, not synthetic. It seems to run well and as I said I think I have changed everything I know of including aligning it, and chking inflation etc to be sure I did my part.
whats your idle like .. should be 600 when in D with Brake On.. should be 700rpm in Neutral
#7
Is 31 the recommeneded PSI? Look in you're arm rest under the cover, check what the psi rating is IIRC its 32 front 29 rear for SE's. What percent are you driving highway and how much city driving are you doing on these fill ups? Also what mods do you have if any?
#8
I actually have it about 1.5 over recommended. Ride will suffer, mileage will be better. No mods on it at all. Driving varies city to hwy but, I am never all city and I have been all highway. The best on Hghway though is 24.5, combo city/hwy is usually 20-22.
I wonder if auto zone or someone like that can tell me if my O2 is bad. It does not throw a code in the car though.
My idle is right at 600 after if warms up a bit in drive and about 750 or so in neutral, no a/c on. It his higher when I start it for a couple minutes.
I wonder if auto zone or someone like that can tell me if my O2 is bad. It does not throw a code in the car though.
My idle is right at 600 after if warms up a bit in drive and about 750 or so in neutral, no a/c on. It his higher when I start it for a couple minutes.
#10
I have it at about 1.5 over recommended and it is different front to back, dont remember off hand but 31/29 is about right. My trips really do vary, but on a highway trip about 60-65 I got the 24.5. If I am all city I will be 19.5 or so. I know many claim to get 30 on highway, and I think I have done everything I know of to do to make sure I am running perfectly, maybe its just too old
#11
It sounds like your doing everything right.
When you ran your Seafoam did you get allot of smoke? Because your pcv valve was so dirty it sounds like the previous owner was negligent on maintenance.
You may want to run some Chevron Techtron through two tanks of gas then do an oil change. I found this to make a difference in my 100k civic. I went from 35 mpg to 40mpg after using Techtron. It should clean up those fuel injectors .
Let us know if you find what works.
HoldTight...
When you ran your Seafoam did you get allot of smoke? Because your pcv valve was so dirty it sounds like the previous owner was negligent on maintenance.
You may want to run some Chevron Techtron through two tanks of gas then do an oil change. I found this to make a difference in my 100k civic. I went from 35 mpg to 40mpg after using Techtron. It should clean up those fuel injectors .
Let us know if you find what works.
HoldTight...
#12
Maybe I forgot to mention, I did the techron deal, but just once. Is it often necesssary to do it twice? I do have Auto RX in it now in te oil. I did have some pretty good smoke with sea foam but of course who can say what is alot or excessive? , is that something that should be done twice? The Auto RX has to stay in for 1500 miles and I just put it in, then the oil gets changed. If I can figure it out I will post so everyone can see.
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