For our new Q members - Preventative Maintenance Story

[OwnerCS]

Here's a link to a story funny about my son's 99 Maxima 5-speed with ~145,000 miles. This applies to Q45s as well.

Preventative Maintenance Benefit on the 99 Maxima from new NTK/NGK O2 sensors:

1) Reduced fuel consumption (at least 15% better MPG)

2) Improved performance (remedied slugish and low RPM takeoff jerking)

3) Reduced risk of buring out the catalytic converter prematurely.

mileage-improvement-preventative-mainte ... 77211.html

My Q45 only has about 18,000 miles on it since the full technlogy refresh that occured couple of years ago. So it still drives like a new car. My daughters I30 (now approaching 250,000 miles) got a technology refresh a couple years ago and it drives great as well.

My 2006 Honda Ridgeline with ~125,000 miles has been using an excessive amount of fuel for the past 7,000 miles. The plugs were replaced with new NGK (factory specs) at 110,000 -- so it can't be plugs. I can't believe I forgot to replace the o2 sensors.. I've been too busy tending to my Nissans..

This is one PM item that will put money back in your wallet each time you refuel. That is if you Q is using an excessive amount of fuel and feels sluggish.

Here's a link to a how-to-thread for the G50 below.

02-sensor-plenum-removal-100-necessary- ... s#p5945324

[Brew Q]

Thanks for posting... I was a little skeptical, but this must be the problem for a recent dive in MPG on my wife's FX (it has 95k). This has made up my mind to go ahead and change the O2 sensors.

replacing-rear-o2-sensor-t528289.html

This is from your old O2 sensor post a couple years ago, but do you remember which 2 tools from Harbor Freight you bought? I'm about to purchase a Q with 80k, but I'll be keeping an eye on the O2's.

[OwnerCS]

Thanks for posting... I was a little skeptical, but this must be the problem for a recent dive in MPG on my wife's FX (it has 95k). This has made up my mind to go ahead and change the O2 sensors.

replacing-rear-o2-sensor-t528289.html

This is from your old O2 sensor post a couple years ago, but do you remember which 2 tools from Harbor Freight you bought? I'm about to purchase a Q with 80k, but I'll be keeping an eye on the O2's.

Here's a link to the original thread with picture of the tools and how I used each type for the different sensor locations.

For the Maxima and I30 I only needed the crow's foot looking tool for the front and an open end wrench for the rear. So the type of tool to make the job easy will vary by vehicle.

02-sensor-plenum-removal-100-necessary- ... s#p5945324

[qship96]

I believe the MPG/performance improvement from changing o2 sensors ONLY if they are not working properly- check my observations on MPG/performance changes from my thread in late 2007,where I drove from MD to T3 in atlanta to service the Q- car had 201,000 miles on it then with original o2 sensors,and 130,000 miles on the ngk plugs,T3 replaced both with factory OEM parts,and afterwards,I turned around and came back to Md- a good long test on the exact same route,to say the least-

PS those plugs put in at 201,000 are still going strong at over 298K.

Here is the original thread-t3-south-cobb-t287955.html?hilit=t3%20atlanta

[Q451990]

I need to do this for my truck. Mileage is horrible for a 4 banger in the summertime. Looking at the lean/rich flips on my scanner tool shows it being a little sluggish - but it's hard to hold the rpms at exactly 2000...

It's kind of disappointing at only 75K, but with the crappy fuel we're getting these days - and probably cheaper parts in 2004 - I guess it's not completely unexpected.

Heath

[maxnix]

hmmmm.....I thought SC had good gas, or at least good prices when I was last there.

[Q451990]

It's cheaper than most places, but we have E10 just like the rest of the country...

[OwnerCS]

I think in my case the short 5 to 6 mile (or less) suburban trips, with 5 to 9 hour rests in between contribute to shorter O2 sensor lifespans. As a side note, this afternoon I changed the (single) O2 sensor on the 95 F-150 and it yielded increased low end pulling power with more pep. I can drive it up a neighborhood hill in 5th gear where it would lug down and start bucking before the change. It was getting 11 or 12 MPG a couple of weeks ago -- so I'm sure anything will help the gas consumption expense. The ~$41 Bosch O2 sensor made a more dramatic performance improvement than all of the new plugs, wires, and filters and all that I replaced last fall. ** MPG test run update on 7/6 (Early AM) it delivered 18.65 MPG. Factory rating was 14 City, 18 highway, 15 combined for a 6 cyl, 4.9 L, Manual 5-spd, using regular gasoline. It has over 241,000 miles. I remember checking the mileage coming down from Fayetteville when we got it almost 2 years ago on the highway at 15. I have one more vehicle to upgrade with new O2 sensors.