I did a few maintenances on my car (2000SE, 5SP, 60k) within the past week. Now my car feels considerably slower. Now when I punch the gas in first or second gear, the rpm rises considerably slower and the gas pedal feels dead if I press more or even when I floor it. Also, I just got 22mpg on highway whereas I usually get 27.

Here are the things I did:
1. Changed oil - used Castrol GTX 10W30
2. Some oil filter that cost $5 at Advanced Auto Parts
3. Took the airfilter out (looked like Fram, paper based) and banged it against a wall many times on its sides and corners to get dirt out. The filter looked pretty dirty.
4. Rotated my tires (front to back, no crossover) myself at my school shop.

When I was rotating the tires, while the whole car was on a lift, I noticed something I didn't like. When I rotated the rear wheels, the pads were rubbing against the rotor and made scratching sound as it was rotating. Other than the sound, however, the wheels seemed to rotate rather freely - one rotating motion and letting go would result in the wheel spinning for several revolutions. I asked the kid that was working there, who seemed to know about cars well, told me that things like that happen on cars with ABS systems and that once you reach driving speeds, the pads will lift up or something like that.

Now, after the kid had left, I tried to spin the front wheels. This thing had a lot more friction going on. It didn't go a full revolution when I spun it. Now, I hadn't spun the wheels before the tire rotation so I don't know how they were like before. This was my first time having the entire car on a lift so I don't have any past references to go by. When I was tightening the lugs, I used an air impact drill with the setting to the lowest, and then used a wrench to tighten some more when I got the car on the ground.

Do you think this brake pad rubbing thing is slowing me down considerably? Does the pad in fact come off the rotor surface as the car picks up speed as the shop guy told me? I checked my wheels after my long highway trip; I didn't notice any significant brake pad dust. Could I have messed up something while tightening the lugs? While taking the airfilter out, dusting it off, and putting it in? Will different oil make such significant difference in torque and power?

On a side note, the reason I didn't get a new airfilter is because the local autoshop only had really crappy paper filter and K&N drop-in filter. I wanted to ask you guys if $45 for K&N was worth the performance increase, if any, and if I should go for one of those cone-shaped ones. So what are your experiences/opinions on that?

What would be some reasonable (I think the school shop is closed for the semester) inspections/tests I can do to trace the problem? What do you think is the most probable cause? Have my perceptions gone mad?

As always, I value any input. Thanks.

oh, and sorry for such a long post

 

Go get a k&n unless u wanna put on an aftermarket intake (IE: Injen CAI or Frankencar etc..), otherwise geta NEW paper filter. That is what is probably cloggin up the airflow into the engine. Knocking the dirt off simply doesnt work.

 

I'm asking for your knowledge/experience/opinion if $45 K&N will offer more value and similar gains as the aftermarket intake and cone filters. Obviously, if drop-in gave me 5hp increase @ $45 and FrankenCar gives me 7hp increase at $100+, I'd go with the K&N. However, if K&N gave me 1.5hp increase, then I'd just get a paper filter for now and get aftermarket intake when I have some more $$. It seems to me that the air intake assembly of the 2000 model is so long and complicated that by the time the air actually gets to the filter in the box, the slightly better airflow of the K&N will not be noticable against a paper filter.

Yes, I know that knocking dirt off is definitely worse than getting a new filter. The engine felt significantly more powerful before knocking the dirt off - using the same dirty filter except dirtier.

 

Yo, the reason why the car run like that is because of engine temperture!!! And not in a bad way its just a little warm. All 2000 maxima's run like that, so its normal.

PS
My max run the same way and I have K&N drop-in fliter, but when the car is cold it a rocket with all the torque and speed you need.!!!!GOD HAS SPOKEN....

 

I don't like K&N, they allow a lot of air borne particles into the engine. Do a search and you will see some heated discussions on this topic. I would suggest the Nissan paper filter as your safest bet.

Check that the "kid" didn't tighten your emergency brake cable too much to try and resolve the "squeeking" brakes in back. If he did that, it could cause a lot of rear brake friction which might result in the symptoms you described.

 

I just recently threw in the K&N replacement filter. It doesnt provide any HP gain (i never expected to gain HP). But the reason I slapped this filter on, is to avoid changing the air filter every 15k miles. So if you want, just go with the paper filter, its the same thing.

 

Exactly...

 

Ah, I didn't know the search feature worked again. Sorry about that.

I guess the temperature might have been it. Because I bought the car 4 months ago (Jan) and I'm in upstate NY so it's just starting to get warm.

Can anyone comment on the front wheel spinning issue tho? To reiterate, when I spun the front wheels, the pads were obviously rubbing against the rotors and it couldn't even do a full revolution. ABS, the "kid" didn't do any work on my car; I did them. I didn't do anything with the brakes since I didn't know what I was doing. Rear ones seemed to be ok. The front ones are what I'm worried about - parking brake only engages the rear brakes, correct?

Thanks all for your input.

 

you gotta remember that your front wheels are connected to the gearbox. They wont spin as much as the rears will, no matter what you do, brakes touching or not. Most of the time, the pads do slightly touch the rotors. But when ur moving, the same air that cools the brake discs causes the rotors to lift slightly. Dont worry about that little thing. As for the temp thing killing power, it is quite common down here in FL. Especially when it gets really hot and humid, the knock sensors really retard the timing agressively, in doing so they cut power and torque a lot. Those w/ intakes will notice the engine is alot quieter than normal. Hope this helps.

 

The gear box! Of course I can't believe I didn't think about that.

After reading all of your replies, I think my max is a-ok. I just got the OEM air filter from courtesyparts and some touch up paint - I need a LOT of this stuff. Thanks everyone.

 

NP man, it happens to all of us one time or another.