Nissan Maxima: 97 Highway fuel mileage

"David Geesaman" <com> wrote in message
news:newsguy.com... 


Maybe. On my 91 w/ 105K I'll get 28-30 at 60 w/o air on. But bump it up to
75 with the air on and it will dip down to 25.

On 9/27/04 9:38 AM, in article newsguy.com, "David
Geesaman" <com> wrote:
 

24 is too low. You should be getting around 28. Run a few more tanks of
gas through it to make sure that one time wasn't a fluke.

The knock sensor sets a code, but does not light the light. You might try
swinging by your local AutoZone and see if they will read out codes for you.

"E. Meyer" <org> wrote in message
news:BD7DB9FD.9F7E8%org... 
you.

I hadn't done many strictly highway trips lately, so if I get the chance
again I will compare numbers. On my daily commute (60% highway), I still
can't get over 21mpg no matter how light footed my driving is. It also
seems low for summer driving without AC.

You know, I've been meaning to do that, but you're right I need to
really check. I had a knock sensor code this summer that I assumed was
caused by the other codes, but if it has reappeared that would explain it
all. (Funny, the plastic cover on the ECU has a new home under my drivers
seat, and I think it will remain there permanently).

Dave

"David Geesaman" <com> wrote in message news:newsguy.com... 

Do a code scan. Knock sensor doesn't trigger the CEL. Also, I'm told
spurious knock sensor codes are common. Scan, if you have the code,
clear, drive, then scan again.

David Geesaman wrote: 

That's probably a couple MPG low and at 124K the knock sensor is
probably gone, but check the codes to be sure (and then reset and check
again in a day or two). If it's no longer working it won't make any
difference if you run 87 or 93 and will lack the punch it used to have.

"David Geesaman" <com> wrote in message
news:newsguy.com... 

I usually get 26mpg or better with no AC at 75-85 mph on my interstate
commute. This on a 97 auto running 89 octane. I'm surprised by
that because my luck with this car has not been great otherwise.

I had my knock sensor replaced in my '99 SE 5SP with 75K and the gas mileage
and performance did improve. I currently get about 22 MPG in suburban
Chicago driving and 26-27 highway.
"David Geesaman" <com> wrote in message
news:newsguy.com... 

David Geesaman wrote:
 
Before you assume the knock sensor, have you thoroughly eliminated all
the basic stuff? Like:

air filter
feul filter
spark plugs
tire pressure

Once those items are checked, then I'd go to the knock sensor.
Also, when a car gets old, rust and corrosion on the ground contacts can
have an effect on how well the ECU is reading everything from the O2
sensors to the MAF etc. I would also consider cleaning all the ground
contact or invest in one of those kits that gives you more ground
contacts on the car. But this would be a very last resort suggestion.

CD