Ok, here is the deal (car: '03 Max SE, Auto, 27k miles, stock)... At lower speeds, (around 30-40mph) when i accelerate smoothly and let the tranny do its job, i noticed that if i'm going with lets say ~35mph and i floor it, eventhough it downshifts the car feels underpowered. It doesn't pull as expected from a 3.5L V6. It starts pulling fine once the speed and the rpm build up but there is that weak spot that i'm noticing. I noticed this behavior few weeks ago but i decided that i could be the colder Cali weather or bad gas so i ignored it. Plus the car run fine all the time, at almost any other speed, without any warning lights. Today, i noticed it again driving around the city. (30-40mph speed) My guess was that the Auto tranny doesn't downshift all the way to second gear when i floor the car and it stays on 3rd the whole time?!? I tried manually shifting to 2nd during one of those sudden accelerations from 35mph but i didn't see a difference. It kind of took the car a few seconds to get real power. Before that it was accelerating very smooth but slow.
Is this Normal??? Am i expecting too much from my Auto tranny? IS this speed/rpm range a weak spot for our 3.5 engines?? Should i be concerned? My car is this "slow" only when i drive it gently in the city and don't rev it too much.

Btw, i timed my car's 0-60mph on Sunday and with the crappy potenzas and a 15 feet burnout i still managed to get to 60mph in 6.8 seconds with my brother sitting in the car. I guess this shows that the engine is runnung fine when driven hard. Or i'm wrong?
Any ideas?

 

actually, you do downshift to 2nd. 1st gear will last thru ~45 mph, thats why when you roll on the gas from a start, it pulls harder at 35 than when the car downshifts - when it downshifts, it doesnt see a need to shift into 1st cause by the time it gets into 1st, it'll already hafta shift into 2nd again, so it just makes its only shift the one to second gear. 35 mph in 2nd gear is a flat spot in the hp/torque curve, thats why it doesnt seem as powerful

 

You might need the "lack of power" TSB. Check the serivice bulletin thread for the specifics. Made all the difference in mine.

 

You can also check here for TSBs
http://maxima.theowensfamily.com/tsb/

 

Haven't noticed anything like that on my 03. At 35 or so I'll put that right foot into it and it'll kick down and haul *** in a hurry- especially between 4 and 6 K on the tach(no performance mods... yet).
Could have something to do with TSB out now on Cam position sensor soldering?
But that 0 -60 time looks about right

 

to answer your question, yes, this seems to be a weak spot in the revband, I dont know why, you dyno wizards might be able to explain why... from your write-up, your car seems to be doing okay, my car is pretty much the same. case in point, on my way up the track a while back, I would hit it from 35 mph on a country 55 mph road, and it would hit that weak spot, however once over 2500 rpm, would pull with an urgency. my Max ended up trapping 94 mph several times ...

if I'm in a rolling race, from "d", I like to go to "3", and hold it there until the race starts, at which point, I manually downshift to "2" from between 50-60 mph, and the car pulls like a train to 80 mph. if I drop the hammer while at 35-45 mph, nothing really happens, its too far down in the rpm band.

yeah, crappy tires = nice tire tracks

Fernando

 

Give us more details. How much mileage do you have on your car? When was the last time you did maintainance? You may need to change your air filter.


~limsandy

 

read the first line of his post.....at 27k he should not need a new air filter and he probably doesn't need maintenance either...

 

If he hasn't changed his air filter before now than its overdue.
Mine was filthy at 16,000 miles last month when i replaced it.