got 117,000 miles - did a "tune up" around 100K...replaced plugs, air filter, got new trans put in, brakes, etc. But before all that and even after that the car just doesnt have what it used to. I noted my 0-60 times back when i got it (60,000 miles) and now the times are almost a second slower..I dont know what to do next. I replaced the MAF sensor on my 00 Maxima and that was a night and day difference in power..but I was actually experiencing noticable problems to have to replace it. The only thing I notice is my engine idles rough at idle...i can feel the vibration in the floor and steering wheel a little. So what other options can I look at to "tune it up" ?

 

Hows your gas mileage, Possiable running on less than 6 cylinders, Coil pack?? IF one of the coils is out or fireing poorly your power would go way down and the idle would be ruff. Compression is good? Have you try cleaning the MAF and or Throttle body? There are a few things that would cause this, Also any retriction on the exhaust, clogged or getting clogged cat or muffler. To much to list but I would start with these.

 

Wow you put some serious miles on your ride... it feels like just last month you got 100,000 .. I remember when u made that new sig..


I would buy a obdII reader and run the car... see if anything pops up... if not then try a local mechanic you trust... just get a 75 dollar diagnoses ...

EDIT: Maybe you are a little tooo tough on your ride... i just read that you said you have gone 148? you are nuts :P

 

Have you done an idle air volume reset, and ECU reset lately? They might help undo the learning that the ECU has done. At least thats what I think they're called. I may be wrong.

CM

 

I have a similar problem.. a bit of vibrating at higher speeds and at breaking, the stearing feel sluggish, and the mileage indicator is starting to go nuts... I feel like I have to fight the car to get it to turn. I am thinking maybe power steering fluid needs to be flushed/replaced?

 

Gas mileage is great..better than I expect when I drive easily on the highway..averged about 27 driving a little hard sometime but mostly highway...i thought of coils but I dont know how to test them without replacing them....cleaned the MAF..no better...cleaned the TB no better....dont know how to check exhaust clog..guess an exhaust shop can do that...
fastmax....lol....I feel special someone notices my sig and when I put it up lol I am pretty rough on my ride though...I accelerate fast a lot..so its prob a maintence issue but I have to figure out what.... :/
I did do air idle volume learn..think I reset the ECU not sure though.

Just...the car does not have this kind of ***** anymore..this was at 60,000 miles.. and no im not usually THAT hard on it.lol vid below

http://www.youtube.com/watch?v=Hnmf5SBQRQc

 

forgot to mention I have the echaust zinging sound at like 2k rpm..havent gotten that checked out yet think it may be the weld bracket problem/tsb . .

 

Is a caliper dragging on the rotor, maybe the ebrake one

 

I recommend you put it up on a lift and turn your wheels to see if you have friction. new brakes and such could cause it. To check your coil packs you need a special tool with a light on it that lights up when the pack fires. You just start your car hook the tool up and then touch the pack and it will flash if its working. if it's not then you have a problem. takes a whole 5 minutes with the tool. Also make sure they are on tight. Don't overtighten just make sure they are tight. This way you know there is a good connection. Also try changing gas stations and putting a fuel system cleaner in the tank.

 

I rotated the tires not long ago so there is no friction..sometimes it feels quicker like a few mins after I start it sometimes...I tested my coils today with a multimeter seems they are all good...tried diff gas stations used fuel cleaner..lucas..other brands...and nothing. i messed with the vias today tried driving with it forced open forced closed forced open did give some good low end tq but after 4K it like..dies..lol so I think the "bring to dealership" is next, it doesnt feel like REAL sluggish just def slower than it used to be..esp under 4K rpms.

 

What performance mods do you have, take them off and see how it drives stock, then put them back on, check intake piping maybe you sucked up something.

 

i just have a berk intake..and even that is stock up to the maf sensor just a filter on the end of it..all connections are tight. i do have the timing chain chatter issue on startup now im starting to notce it after use of high rpms...i may have to get that fixed next....eek mucho denero $$$