Finchum

What's up org? I have a question that I want to ask the other auto guys on the board.
I am now in my 2nd week of ownership and have noticed some things.

WOT from a stop it absolutely hauls in first gear and then kinda sets into 2nd and doesn't really pull hard at all through the gear.....

For arguements sake....when I am cruising at 45ish and go WOT it kicks down to 2nd gear and hauls butt like my first gear does from a stop. Power diminishes in the same fashion upon shifting to third.

My question is, do all the 4AT's behave this way? And what can I do about it? My gut feeling is the VIAS and fluctuation of the valve....but I will leave it to y'all to decide.

I made a cardboard template of the vias gasket and my step dad is gonna make me a block off plate.

AznRyan

iTrader: (1)

CXJPerformance makes a well-designed bop for the VIAS for $10, although IIRC they slightly hamper low end performance, and add hp in the upper end of the power curve

T_Behr904

NWP also makes a block off plate. He's been making parts for our Maxima's for a long time now and is a respected member of the community. Or, you can buy "the other guy's" plate or make your own. Either way.

Also, the 4 speed auto in the 00-03 Maxima's isn't known for it's all-out performance. That's why the manual transmission is preferred with enthusiasts.

Ryan95gle

Transgo Reprogramming kit

Rods03Max619

iTrader: (5)

Probably about right especially stock, I got some Vids in my Sig on youtube to compare to if you like....

Yoitsme

iTrader: (2)

I see no reason to disrespect Cory by labeling him the "other guy"....I have both NWP and CXJperformance BOP and it's not like his is of any lesser quality deserving to be called the "other guys" product...that is all

ChrisMan287

iTrader: (34)

Agreed.

03VQMAX

iTrader: (46)

So your 3rd gear doesn't pull? My 3rd gear wants the engine to jump out if it's compartment..

AznRyan

iTrader: (1)

You have an 00-01 Max or an 02+ Max?

KBCobra

I have an 00 4AT and mine pulls from first and starts pulling less and less as I go through. Must be the Automatic transmission. Go 5MT! lol

Finchum

its a 2003 SE, sunlit sand, 150k on the clock, black aftermarket leather.
I have installed ground wires and H&R springs so far. The BOP and tint is next.

Step dad is making it for free, cnc/tool/die playground at his disposal .

I wanted the 6mt but wifey had the final say when we stumbled across this steal of a car. with two car seats in the back for my twin 2yr olds, the auto was the path to take. I KNOW i will be grabbing the transgo kit asap.......I just have to make sure there inst any tranny issues by my description since I am learning how it drives. It definitely has potential for a nice grocery getter. I am hoping its just the vias junk kinda fluctuating after prolonged acceleration(5seconds or more). Anyone else feeling that way? Or do I just need to get the I/H/E toys on it pronto and quit worrying about it

luvlexus101

iTrader: (6)

If you run 1st all the way to the end and you catch second around 4k rpms it'll still haul. Its just until you hit that part of the power curve it won't haul especially stock and the bop isnt going to help that.

I believe a transgo kit will really only help with the shifts but it won't haul the way you want because there would be no real increase in motor output.

T_Behr904

Well, he is the other guy. And it's not just the bop either.

guarj17

To start off, my post is totally my opinion and how I believe my car pulls. Will post videos of all different pulls of my car at different speeds to prove my comments...or prove them wrong if my numbers do not seem correct. I have not given my car a good pull in a while and posting off my memory. I have no problem admiting if I am wrong after taking videos.

Finchum, I also have a 4AT, I will give you the layout of how my car runs. I have 136k miles. I have an Injen CAI, and a NWP VIAS BOP. IIRC, From my 0 mph WOT, I have a full pull with perfect shifts. Going WOT from about 15-25 mph (I think, might be a little off with numbers) car will downshift to 1st and give me a full pull. At a certain speed, I believe around 35-40 mph, if I go WOT the car will not downshift and it will slowly gain in RPM and around 4k RPM I will start to feel the pull again.

Anyone with an AT, please let me know if my description does not seem correct. Could either be my car running as it should, me not describing it correctly, or my car not running correctly.

Finchum

ok, I am thinking the stock condition is the only issue at hand. plus.....

One very important piece of information that I forgot to mention. This is the car's first tank of 93 octane. It's spent the majority of its time with the previous owner with 89 octane in the tank.

The front spark plug I checked looked rough and needs replacing. I bet was ignition is timing being pulled from gas knock? It would explain the power's fluctuating feeling. New theory, thoughts?

kbcnd

iTrader: (2)

I have a 4AT with KYBs and Vogtlands and a custom SRI. The way y'all are describing the pull seems to be what i experience as well. It will pull all the way to second gear then drop off and the speedo will slowly climb. However, if I throttle the gas (after it gets to second ill let off the gas and reapply it) and most of the time this will cause the car to continue to pull as of it were in first. If I'm cruzing on the highway and go WOT, sometimes the car will downshift and pull like crazy, other times it stays in gear and the SRI just makes a lot of noise. Hope this helps.

AznRyan

iTrader: (1)

The AT's in these cars aren't really geared towards performance. Of course a 5MT/6MT is gonna perform better than a modified AT, but some members like the SupraStick mod for auto's

VQMagic

iTrader: (1)

This is how mine is. OP remember pretty much all the gears in the 4AT are rather long. 1st gear is 0-45mph, 2nd gear is 46-82, 3rd gear is 83-130- and 4th is 131-145.
^^This is all my personal experience so mph might be slightly wrong but pretty much accurate. Either way though as my car is right now, it goes through all the gears a TON faster than stock. Every gear pulls pretty hard from about 2.5k rpm all the way to redline and doesn't lose steam at all even near the MPH limiter.

CMax03

iTrader: (3)

Finchum place the selector in 3rd and do a pull! The jump from 2nd to 3rd is larger gear wise than a 5spd or 6spd! But I would highly recommend you replacing your spark plugs! My pull is violent all the way but I will say that the electronic throttle has a mind of it's own and stomping it isn't the best way to go, but going in 7/8 of the way and then flooring it seems to be the way it pulls better IMO...So if you could install a Sprint Booster it makes the throttle react a little better ad may have a better affect on your WOT escapades!

kbcnd

iTrader: (2)

What did you modify to get it to go through all of the gears faster than stock and increase your pull?

VQMagic

iTrader: (1)

See my sig. I have just about every bolt-on plus SSIM. Also having a single 3inch exhaust mocked up shortly. I've done nothing to the transmission directly. This is my 3rd 4AT trans though. Reman straight from Nissan. Have about 35,000 miles on it and its great. The one thing that absolutely DESTROYS the 4AT's is wheel spin!!!!!! I've learned that the hard way and paid out the *** because of it. The transmission heats up so quickly while the tires are spinning and it can ruin it just spinning them a few times for more than 5-10 seconds. If I get even SLIGHT wheel spin now I let off the throttle. Fortunately for me, When I run the 1/4 mile over at Englishtown, NJ, My race tires yokohama S Drives hook up perfectly and I get minimal spin if at all.
I went to another track called Island Dragway in NJ two years ago and there prep job was horrific. I spun through 3/4ths of the quarter mile.

Finchum

freshly installed springs...i love the anticipation of the springs settling down another inch in a few weeks. They did that on my 05 Alt 3.5se and 07 G35Sport when I first installed h&r's on there.



0-70(appologies for the sunlight)...i count a long 4 secs between 50-70. It shows what I am feeling.



45-80.....I count 3 secs from 50 to 70 and it shows how It feels like a rocket where it is slower in the 0-70 vid.



I plan on getting some new NGK platinums next week, and some NWP spacers after that. So probably in a few weeks I will be doing a thorough cleaning of the whole intake tract which should wake her up some.

Side question. We will continue to focus on the weird acceleration on the 4at in different circumstances. But, on all my previous drive by wire cars that I seriously modded, I would do a throttle body port match job to the gasket with great results. Anyone done that on the 5.5gens? (great results=smoother dyno graphs and improved throttle response)

02max245

iTrader: (2)

My car has a similar problem 3rd gear for some reason is slower. ill try a pull from 60, the trans downshifts to 3rd and the rpms barely climb, and when 4th hits it begins to take off.

NmexMAX

iTrader: (22)

Seems normal to me, what doesn't seem normal is that your SES light isn't on.

(sarcasm)

nishfish871

iTrader: (5)

Hey! Respond to my pm!

zzmmrx0xmzz

sighh wish I had a 6mt

Chris Gregg

iTrader: (59)

I have the 4AT and your description sounds par for the course. I've always chucked it up to this being an issue because of where the power band/rpm falls when it downshifts under those conditions.

I'd like to say it's a crappy programmed TCU. But, when I've watched the rpm's when this happens for me, at the speed I'm going at that time....I know if I actually shifted down into first, I'd only have about 6-800rpm before I'd redline. So, even though I may not be pulling as hard as I'd like at that point in 2nd gear after downshifting from 3rd, I know it would really be overkill and result in bashing upon both the engine and transmission unnecessarily.

Anytime my downshift from 3rd into second on the interstate/highway to pass, where the rpms are in the upper midrange....she pulls like a scalded dog.

So, is it normal? Yes.

Is there much you can do about it? Not much. IMO, best mods to help would be a good SRI setup, headers, y-pipe, and 3" exhaust.

Will a Sprint booster help? No. Full throttle in a weak power band is just that. Sprint Booster doesn't give you 125% throttle. Though, no doubt it will contribute to a more "spirited" driving experience.

02AutoMax

Seems perfectly fine to me. Your tranny seems to shift fine compared to mine. Granted it should be faster from a stop.

It doesn't seem to want to redline and therefore when it shifts drops out of the powerband when the vias is fully open causing the slow time.

maximase86

iTrader: (24)

Are you feathering the throttle from a stop? I usually have traction problems from a stop. Then again, I'm running a few more mods (Popcharger, Spacers, cat-back, transgo kit), but my torque convertor stalls insanely low (i.e a few hundred rpm's off idle, this isn't on purpose, need to talk to the guy that rebuilt my transmission...still), so I get a nasty bog, then all hell breaks loose.

S

Finchum

Update. Installed the free BOP.

SHE'S ALIVE! mwuhahaha

seriously, its pulling hard and breaking tires loose in 1st and 2nd. I am playing around with flooring it slower and keeping the throttle around 7/8 down and its not bogging down like the videos above. First thing I did on the straight going through 1-2-3 was ....and then I said aloud to myself, "wow it does have potential".

I can't wait to piece together the bolt-ons and tune it in with an afc. I still absolutely despise the fact technosquare's tuner went back to japan and they stopped tuning ecu's stateside! They had the best numbers on 350/g35/altima/maximas. Thanks for all the replies gents!

02AutoMax

That's good to hear! Just wait til you get some bolt ons. It will turn into a Honda with the kick around 4k but only difference is we have torque. Haha

NmexMAX

iTrader: (22)

Add an ETL, PUR engine torque mounts, and a VB mod, and you will never ever regret it.

Or at least I don't. Pretty sure my tires regret it, but not me.

kbcnd

iTrader: (2)

How much low-end power did you lose? Was it really noticeable?

NmexMAX

iTrader: (22)

Pretty sure it's inversely proportional, as in the top end gain will be amplified by the fact that he lost mid-low end.

Also, pretty sure he doesn't have a dyno to put an actual # on it.

luvlexus101

iTrader: (6)

Why is it shifting so far away from redline?

NmexMAX

iTrader: (22)

That's what happens if you don't manually shift an auto.

junglee Z

iTrader: (5)

in a 4AT first gear and second gear pull hard. third gear is like hitting a wall. i had a fun run with a '01 maxima vq35 5MT from a roll. through first gear and second gear it was dead even. as soon as i got into third gear i got walked. do a 6MT swap.

Finchum

kbcnd- The torque loss in my honest opinion wasnt really noticeable. The car already has plenty of torque, so even if it did loose some there is plenty there that I dont care. The power past 4k is awesome!

luvlexus101- was holding the phone and couldnt shift it manually....auto likes low shifts.

junglee Z- Yea it now runs amazing up to 80ish....whats your opinion on the NWP spacers? Should I go for em when I get ready to change my plugs and clean the intake tract?

02AutoMax

The spacers are the best midrange gains for the price. Once you install them you will completely forget about the loss in power and actually pick up some in the midrange. If you are going to change the plugs I would go ahead and get the spacers.

Scottwax

iTrader: (8)

The BOP plate definitely helps. First thing I noticed was power delivery was more linear, second thing was instead of automatically upshifting at around 6200 rpms, it was upshifting at 6500 rpms. That change was immediate and permanent.

However, after a drunk totaled that car and I got a 6MT, I would be able to go back to the 4AT, the difference is that much.