My Maxima 98 takes to much fuel. About 240 miles on full tank. What would you advise to do ? I consider to change spark plugs ...but I do not know which one to choose ?

Thank you.

 

Read the stickies at the top of this page.

 

Read the stickies at the top of the 4th gen forum! I think it's FAQ's second page. NGK copper plugs=12 bucks for all of em, clean iac valve and throttle body, air filter, check for knock sensor code etc. read a little bit and u'll figure it out

 

Doesn't hurt to calculate actual MPG either.

 

240 miles on a tank is absolutely horrendous. I have had as much as 550 on the highway and consistently get over 500. I also routinely get 350 in a stop and go commute of 11 miles each way.

 

plus, if u have auto ur mileage will be worse than with manual, but yeah, calulate REAL mpg, dont go for "miles per tank" cuz ur needle isnt that accurate. Fill up, set trip odom, drive, fill up, divide miles on trip by gallons to fill up

 

Which one is better :Spark Plug Platinum+4 Bosch or PFR5G-11 NGK ? What is a difference ?
I want to change spark plugs for BOSCH Platinum 4 and Fuel filter, my Air filter is clear, I changed it like 3.000 miles ago so it is clean for now .

About MPG - in city it's around 11-13. But lately even on Highway - it was very bad.

Thank you for fast respond.

 

any CEL codes or ghost codes ?

 

Spark Plug PFR5G-11 NGK F1000-57290
and
Spark Plug Platinum+4 Bosch F1000-61924

That's all codes what I have.

What MPG must be for Maxima'98 ? I mean good enough for 7-year-old -car ?

 

Everyone including Nissan recommends NGK.
I got the Bosch +4, they are really good plugs as well.
For reference, when i did my lil tun up (plugs, pcv, fuel filter, oil change, tranny flush) everything made a HUGE difference in performance and drivability.

To get better mileage do the following:
-oil change
-spark plugs
-pcv valve
-fuel filter
* depending on mileage your KNOCK SENSOR and O2 sensors might be bad. If you are above 90K you should check it...look at the stickies for all this info.

I think I'm too nice sometimes

 

Check for the hidden 0304 code: http://forums.maxima.org/showthread.php?t=104931

If you get a 0304 code then you need to get a new knock sensor and depending on how many miles you have, you might need new oxygen sensors http://forums.maxima.org/showpost.ph...6&postcount=39

Isn't that gas mileage range normal for NYC? http://forums.maxima.org/showthread.php?t=369675

http://forums.maxima.org/showthread.php?t=289189

 

What does "to a tank" mean? Nobody I know fills the tank, and then drives it beyond the reserve and then looks at the miles traveled. I'm with the member who said it wouldn't hurt to calculate mpg. After that vacuum vs. pressure go back to physics 101 class post yesterday, I realized the engineers on the forum are few and far between!

 

240 miles is normal for NYC driving

 

Mileage is going to vary greatly depending on how/where you drive. 2 weeks ago I went on a trip to Manhattan and back, and averaged 28.5 over 225 mi. or so. The car never hit city traffic because it went straight to the garage, so that was all highway miles with no backups, because I left early in the AM and returned late at night 2 days later. My car is also a 98 with 103k.

I have kept a spreadsheet since 0 miles, and the avg. is 24.1. But that means nothing, as I have never (over the last 4 years) taken my avg. and gotten 24.1. (mean median mode eh?) Usually, when I am strictly stop and go with 8 of 14 miles of my commute per day being highway, I get 19-21 depending on how much back-up there is.

The only way you're gonna get a good figure is to take your car on the highway for at least 100 miles each way, 200 miles round-trip. Then the next weekend, do the trip again. To me, the highway mpg is an indication of how the motor is running. I wouldn't worry about low mileage if the car never sees the highway. Good luck.

 

I admire your rigourus documentation. Can't argue with hard humbers like that. Think you are dead on with the highway comment too.

 

240 miles on tank is not normal , like half year ago I used to make 320-350 miles in the city.

P.S. By the way my Maxima has 110.000 miles on ODO .... may be that is a reason , I drive it 1 year ...but I think that spark plugs or fuel filter never been changed. I will try to do it soon and Post a result.

 

http://web.archive.org/web/200111091...k_service.html

 

Hey what's up bro, well just want to let you know I had this same problem but I was using 87 octane gas, and didn't replace my spark plugs cuz I thought the prior owner of my vehicle took care of that before selling it. Anyways I changed to using 93 octane which infact did help in gas milage, but then I noticed my friend V8 mustang wasn't sucking up as much gas as my V6 jap car... which is odd of course. Anyways I thought maybe just maybe it could be the spark plugs, so I checked one of my spark plugs and it looked as if the spark plug was beyond normal (they looked fried), so I went to NAPA and got V-Power Coppers by NGK and replaced the spark plugs, btw the Copper V-Powers are pregapped as from what the guy at NAPA told me, then again I should have checked to make sure. Anyways now gas is finally not being sucked up like a vampire... I was going to knickname my I30, "Vampiro"
(Spanish for vampire)

 

always I put Gas 93, couple times I put 89 - I did not see big difference in power ..... probably my Plugs are burned and dirty

 

mine is suckin up the knock sensor, its probably my knock sensor (ghost code 0304). hope it helps! im lookin at about 17 mpg

 

I am trying to find copper Plugs , but thats all what i found http://www.sparkplugs.com/results_a.....803

Anybody has any idea where on-line I can buy Copper Plugs ?

 

Cheaper at local stores (the dealer probably has it for ~$2)

http://www.sparkplugs.com/results_cr...E-11&x=64&y=16
http://maxmods.dyndns.org/index.php?MaximaSparkPlugs

 

I've had 2 96 maximas now, 5spd and auto, and they both have bad gas mileage. Chances are that if you're getting bad fuel economy, no matter what you it won't get much better.

 

DAVE Sz, did you try to change Plugs & fuel filter ?

 

I'm assuming 240 a tank means he goes 240 miles and then the fuel light comes on which means you've got about 3 gallons left so he's getting about 16-17mpg. I must this a crappy way of gauging MPGs though.

How quickly we forget that we're in the dead of winter. Cars run extremely rich on a cold start up and get about 8-9 mpg in the first couple miles of a very cold start up. Add in short drives, stop and go traffic, and the most significant MPG killer........winter gas. This year in the US a new type of winter gas was introduced and I don't know ANYONE that is getting the same MPGs they got last year during this season. My MPGs in my 5 speed Maxima was a dismal 17mpg in mostly city driving when I usually got 19mpg during this season. My wife's Subaru Legacy GT wagon auto is getting 17mpg when it use to get 20mpg in this weather. My G35 is getting 17 mpg in the city. Ouch!! Take a look and ask around. Take notice to how many people are complaining about thier MPGs right now. I think a 10-15% drop in MPG can be directly attributed to winter, cold starts, and cleaner burning, but lower energy winter gas.

 

Dave B, according to your commnet - their is no point to change, just I have to wait till summer :-).
Today I was at dealer and they told me that I have to buy NGK Laser Platinum - it's like $15 ???? And that guy told me that on this Plugs I can make about 100k miles .

 

Maxima MPG is pretty good, but my paretn's Lexus 1997 ES300 (w/225hp 3.0) gets over 4MPG more on the highway and with city trying. More efficient engine - and faster.

 

I think 100K miles on any spark plug is BS

 

I changed Transmission fluid - it was "dark cherry" and I changed fuel filter (that one was really bad) .... so far my car is moving more smoothly .
I will se what is my MPg will be

 

Personally I would avoid the Platinum+4 Bosch plugs. I had problems with them in the Maxima. I pulled them after 30k miles and one was missing all 4 electrodes. If you do a search you'll find quite a few posts by people with simular problems. I've never read a complaint about the NKG platinums. The coppers are OK also but need to be changed at 30k miles, as the dealer said the platinums should be good for 100k, I change mine at 60k but have never had any that didn't look OK. As far as price try some of the discount mail order dealers:

Conicilli Nissan http://www.trademotion.com/partlocat...cfm?siteid=840
Courtesy Nissan http://www.courtesyparts.com/
Jerry Rome Nissan http://www.jerryromenissan.com/en_US...mePage_1.chtml

Jerry Rome offers a discount for Maxima.org members I think the current discount is 12% but they sometimes have sales posted in these forums with bigger discount codes (up to 30%).

I've used all three in the past with good results, and depending on the discount I can get Nissan parts cheaper than "parts store" prices.

 

Ive also heard the bosch plugs nd nissan dont mix, ive dealt with your exact problem only my max was worse 250km nd i dnt mean miles, im canuck, i had a hardcore tune up done including the throttleboddy and my first tank since is currently round 240 kms over a half tank, when b4 it would be just above empty goodluckto you man

 

to [Me[kk]A] : Could you describe what exactly did you : what is"hardcore tune up" and how good is MPG now ?

Thanks

 

right now I have NGK VPower Coppers, pregapped and I'm getting a hell of a lot better gas mileage than last time, my last plugs looked close to ashes.. they were mighty old.

 

Just did a tune up:Fuel Filter, clean IAC, Spark plugs, got a new KS. have weapon R intake and budget y-pipe. Aways 93 grade gas im getting 17.5 mpg oh ya its an auto too.do alot of high way to work, and city when moving around. Can a bad or dirty PCV valve really lower mpg that much?

 

i dunno about the pcv valve. i tried to get mine off, but i cant. maybe im a pu**sy, but i didnt wanna break anything. it seemed pretty stubborn. any suggestions?

 

Yeah, that doesn't seem too bad.

 

Of course, that's the first things I do when I get a used car. It's just common sense.

 

If the PCV valve is gummed up, there will be less ventilation to the crankcase (re-burning of some gases before being expelled into the the cat) which tranlates into dirtier exhaust but not typically dramatic effects to gas mileage. If your PCV valve is stuck closed, you may experience harsh idling and some mileage issues. If stuck open and your engine backfires, that is potentially dangerous.

 

ditto on the Bosch +4's, if you okay with changing them yourself, save the $$$ and use NGK coppers often, just my 2 cents

 

Pertaining to my tune up, i had the throttle body cleaned, and ran the cleaner through the engine while it was running, changed my plugs to NGK platinums, changed my oil, threw in some mobil synthetic 5W 30, flushed the tranny, put in some dexron 3. considering i was getting 260km/ 60 litre tank im now at 253 kms at half a tank, so the difference is tremendous