Whiggy

When in 1st, 2nd, and 3rd gear I let off the gas even while driving slowly the engine brakes kinda hard and that seems to be normal for most cars with manual transmission (although not all manuals are the same).
However, this happens in 4th and sometimes even 5th gear. I think only in 6th I don't feel the engine braking hard. It's driving me nuts! I have a lot of meandering roads in my neighborhood so I have to stay in 2nd or 3rd until I get to the main road. There is just no way I can let off the gas without shaking up my passangers, no matter how slowly I do it. Note: I am not a newb with manual transmissions (about 15 years) and I have been driving this car for about 10 months every day, so I am used to how the car drives. I've driven many different manual cars but this one seems impossible to drive smoothly.
Is this normal or is there something wrong with my car?

Nismo3112

iTrader: (12)

Not sure if that's normal or not, but I would try driving another 6spd to see if it does the same thing or not.

MyBlue02

normal unfortunatly , mine feels like theres play in hte mounts so i am going to try some solid es motor mounts to help.

the 5.5 6spd is one of hte hardest stick to drive smoothly from what everyone says

NiSmOVQ35

iTrader: (1)

you need new motor mounts.
When you left off any ANY GEAR the engine lets the rpms down a lil, the mounts hold it motor inplace so you dont feel those rpms dropping.. your mounts are ****, so you feel it alot more.

nismology

iTrader: (8)

I don't think that's what he's referring to. Stiffer motor mounts might cover up the issue, but doesn't get to the root of it. I believe it's because the ECU holds the throttle somewhat open upon deceleration, increasing the engine braking effect. A japanese tuner that built a 350Z for road racing noticed this and because of it opted to go to a convential cable-controlled throttle setup. I would imagine the maxima's ECU is similar. Perhaps a TS reflash could remedy that.

Whiggy

I think all of you guys might be right as it sounds like a combination of things. To attempt to furhter describe the behavior - when in 2nd or 3rd I let off the gas (even when I do it gradually and as slow as I can) the movement of the car feels like it "bounces" off the tranny in the same manner as a ball bounces when you drop it - starts with a long bounce, then a shorter one, then a shorter one.... until it settles (somewhat).

How much does it cost to replace the mounts and is it a DIY?

huffdaddy2008

iTrader: (1)

I think your mounts are fine. This is just the way the 6 speed is. I always just push in the cluthc so that it doesnt shake/bounce.

LA02MAX

iTrader: (3)

I know exactly what you're talking about, but I can let off the gas smoothly just fine...you just have to get a feel for it.

And LOL @ the 'hard to drive' comment. Our cars are very easy to drive smoothly because of the long pedal travel and not so grabby clutch...try something with a short stiff clutch...

DasYears

for your everyday car, it is harder to drive (rougher) than many or most. sure its not as hard as a car with a 2" travel and 6-puck clutch, but thats not an everyday car. as for the topic, i either dont have that problem or dont notice it outside of first gear. first is a huge beech to be gentle in, but all my other gears i have no problem being smooth with

Maxim(a)SerjVQ

hmm. . .is this car modified at all? when you let off the gas, the flywheel is supposed to maintain the inertia produced from the engine, and keep the car rolling. what you're describing sounds like something produced by a very light flywheel that doesnt maintain the force generated by the engine. Thus, when you let off, the force keeping the car at a specific speed is immediately gone. I think at one time or another there was talk of putting a 350z clutch/flywheel on the 5.5. . .try searching for something relating to that. Also, the ECU may be an issue like nismology said. worth checking anyway

boondoxmax

iTrader: (1)

Its normal. That's just the way the 5.5 is. It drives me nuts also. Very touchy throttle......

rocketsled

i only have noticed it in 1st and 2nd gear...i just figured that was normal

SoonerFan

iTrader: (5)

result of the "drive by wire"
once you get used to it, its fine

Whiggy

I wish there was a stock 5.5 gen for sale where I live so I can test drive it and compare but there doesn't seem to be one within 100 miles. At least not listed on AutoTrader.
As for getting used to it, I think after 10 months I would have gotten used to it if everything was OK.
I guess I'll check the motor mounts and reset the ECU and do the throttle position relearn and go from there.

zero2sixtyZ

iTrader: (30)

I was searching and landed on this, but double check this:
http://maxima.theowensfamily.com/tsb/NTB03-022.pdf

Hesitation TSB for 02-03 6MTs. I got ES Motor Mounts and still have this problem.

MintVQ35

iTrader: (1)

I notice it in 1st but what you are describing sounds pretty extreme like it could be a motor mount(s).

Eirik

iTrader: (2)

Horrific bump, I know, but it came up while Googling.

Did you ever look into "fixing" this at all? My car did that until I reset the ECU and did the accelerator, throttle, and idle air volume relearnings, then it went away, COMPLETELY. It was shocking, actually, revving the engine up in second or third gear to any speed and letting go of the throttle to experience... nothing. The smallest waver in rpm as the engine seems to "catch" itself, then smoothly, slowly decreasing rpm as the car decelerates under its own power. It was 2:00ish in the morning so I don't remember if I tried it in first, too, but assume I did and don't recall it yanking me around even then. Though my idle speed has gone back up to ~700, the smoothness when abruptly releasing the pedal is still there.

I've seen someone else mention that performing the two pedal dances and ignition switch dance (okay, the latter is not catchy) fixed the herky jerkiness, too. I still have to have my car taken in to get the ECU reflashed to fix the hesitation and refusal to get the idle speed to stick at 625+-50 ANNNND, since it's a December '01 build, a new MAF sensor , and the vibrating hood nonsense, even though my car is out of the range described in that TSB, NTB02-005.

NmexMAX

iTrader: (22)

Dude hasn't logged in here for nearly 8 months, so

SoonerFan

iTrader: (5)

Eirik

iTrader: (2)

He could be, uh, lurking? ...

Yeah, so I lied. The jerkiness came back when the SES light came back on, then the SES light went away on its own and the jerkiness remains. The idle speed went back up after one restart. =/ Just saving up for the MAF + flash to hopefully put an end to all these shenanigans.

Rochester

iTrader: (3)

Eirik, if you improved this situation by applying the relearn/reset procedures, but then it came back again rather quickly, maybe the Throttle Body is suspect?

NmexMAX, bumping a dead thread is fine when on-topic. Although directly addressing the long-gone OP is kind of odd.

Eirik

iTrader: (2)

Rochester, my reasoning kind of goes like this:
1. Accelerator pedal sends a signal to the throttle body to open the valve.
2. When you abruptly release the accelerator pedal, the valve goes from partially open to fully/almost closed, which equally abruptly chokes back the engine.
3. The passengers feel the engine hesitate as the RPM jerk down, causing it to no longer be in sync with the gear.
4. The ECU re-opens the valve to match the engine's RPM to the transmission's RPM (causing another jerk) to let it slowly close as the car loses speed. Sometimes, it can't seem to perform the "slowly close" part, either, and the passengers experience multiple jerks before it settles down.

I believe that the fix causes the ECU to more quickly grab control of the throttle body to prevent that jerkiness from occurring; you let off the gas and the throttle body's butterfly valve stays at the position you last left it, only closing more as you brake/coast/decelerate to keep the engine's revolutions matched to the transmission's revolutions. The combination of resetting both the throttle valve's position sensor and the accelerator's pedal-height sensor must give it enough accurate information to keep the synchronization going.


My understanding of how the whole process works is very limited, so everything up there is conjecture. If I'm way off in that hypothesis, I'd appreciate someone's more knowledgeable correction on how the throttle body and its valve interact with the engine.

NmexMAX

iTrader: (22)

Codes?

Rochester

iTrader: (3)

I've always experienced this jerky behavior since the day I drove the car home, 8 years ago... before and after mods. I moderate the effect with driving behavior and being sensitive with the throttle when decelerating without braking. When that bouncy, jerky behavior happens, my thinking is "shame on me", not on the car.

Perhaps what I think is normal is something that you're trying to diagnose as a problem? Then again, you've got a CEL, so I really don't know... I just thought I'd toss out "Throttle Body" and see what sticks, because a failing TB can cause a CEL.

NmexMAX

iTrader: (22)

It (problem w/throttle body) would probably also put it in FS mode, which he is not experiencing.

And from the general consensus from this thread, it seems as if it's 'normal'. But, interesting that it went away, and 'came back' with an SES light.

Rochester

iTrader: (3)

His SES is what makes me think there are 2 separate things here: (1) jerky, bouncy behavior when decelerating in gear without brakes, which is normal and avoidable in your 6MT when you're on top of things. And (2) whatever it is that Eirik is experiencing.

If there's a SES, then there are codes to pull and diagnose, right? That should be his next step.

Eirik

iTrader: (2)

Yes, it's been fussing about a Gross EVAP Leak for several months. I pulled the gas cap off to heavily clean it, Armor-Alled the seal/ring on the cap, sanded off the rust on the gas tank's neck, and, finally, sprayed it down with a gray Rustoleum primer and then two coats of black, gloss "automotive" Rustoleum. I was waiting for the light to come back on and assume that's just part of the same problem. I'll try and get the codes checked and cleared today to confirm it's still EVAP stuff.

Does anyone know how to use the Snap-On MODIS tool? We've got one at work and I've used it to clear the codes on the Max before, but wonder if I can use any of its advanced features to check for some other failure/help diagnose other things.

I'll reset all the parameters again today and see if the jerkiness still goes away when doing that. Like I mentioned before, I assumed it was normal and could only be combat by adding ES brushings everywhere, but then I read someone else describing symptoms of the IAV being too high and they mentioned the jerking and fixing it by performing the IAVL

Mayhaps the jerking is simply more severe for some cars? Mine's bad enough that you get physically yanked forward and back as if you were in a minor fender-bender, the engine makes an audible WHOO WHOO WHOO noise as it bounces, and the RPM bounce +/- 300 right along with you. There's nothing like that in fifth or sixth gear, of course.


PS: I think you two are my favorite members I have seen on here so far.

NmexMAX

iTrader: (22)

For 8000$, it better do more than read and clear!

I've heard this issue being dealt with by doing all the pedal dance/ignition stuff (IAVL, etc). But yours seems to be intermittent and more extreme than most. I don't think the EVAP has anything do do with it. Have you checked under the rear, left (opposite of muffler) for damage to the EVAP canister, might be banged yp, it's plastic, so easy failure.

Rochester

iTrader: (3)

This is a much more severe description than what was being interpreted as normal engine braking. Seeing the tach bounce... that's not right. If it's easily repeatable, sounds like you need to take it to a Nissan shop and suck up the diagnosis fee.

Good luck. (Favorite Members? Meh.)

NmexMAX

iTrader: (22)

In my years of dealing with Nissan they don't know much about these cars. They will read the FSM word for word and start from the top replacing shti ... until it goes away. Too pricey IMO.

Get the codes read using that nifty little contraption. If that thing can log APS & TPS data, do that too.

Worst case, buy a junkyard TB, install, and try again. I would also do the IAVL once more too.

Sterling

I'm kinda jumping in the fire here - I read most of the replys but it sounds like the OP is saying he is letting off the gas COMPLETLY in first second and 3rd?

Those are all tough gears because there is alot of power in each of those gears to get the car going. I would suggest, seeing that OP is maybe new to stick (10 months) and the "drive by wire" ecu to adjust with the clutch upon slowing down rather than just "letting off the gas"

I mean you could be just before WOT and then you're letting off the gas causing the "bumpiness" try letting off slower on the gas and if your high in the RPMs and want to remain in gear try using the clutch to maintain full control that knocks out all bumpiness- also try going into a higher gear 2nd to 3rd and brake from there going into neutral - same for 3rd going into 4th

The 6spd is great once you understand how to drive the drive by wire

Eirik

iTrader: (2)

I'm new to the stick, the OP says he wasn't. The only other manuals I drive are medium- and heavy-duty diesel trucks weighing 12000+ lbs. They definitely don't do the same thing, but those massively-powerful six- and ten-speeds simply can't compare to my car's six, of course. Eaton-Fuller or Allison transmissions, Detroit Diesel, Cummins, International DuraMaxx, or CAT engines... Regardless of the combo, the trucks just don't work the same way. Is it the absence of synchros that makes the difference?

My car just seems to be extremely sensitive to not being on the throttle, so I'm either accelerating or have the clutch to the floor, braking. There are few situations where I can ease off the accelerator slowly enough to avoid the jerking or will be braking lightly enough to stay in gear. In those situations, I'd typically clutch-in, shift to neutral, clutch-out and coast anyway. I just don't want to wear my clutch out prematurely, so the fact that reseting those parameters fixed the jerking piqued my interest, for sure.

So, no, I don't normally just drop my foot off the accelerator pedal like an automatic. I was just being as extreme as possible while testing to verify that the car behaved differently after the resets.

I work for Penske Truck Leasing, so there's only one guy at our shop who knows the ins and outs of the MODIS. We use it to diagnose problems with any of the gas-engined trucks and cars in our fleet; all the diesels have far more sophisticated software that connects via Bluetooth. I'll pick his brain the next time I see him.

No, I don't think the EVAP leak has anything to do with this problem, but I'm betting that's why the SES/CEL is on.

NMex, I assume APS = accelerator pedal sensor and TPS = throttle position sensor? I'll look into it.
Rochester, why the sarcastic face?

NmexMAX

iTrader: (22)

My car does the same, (+/-300 or more RPM) in 1st and 2nd when I leave it in either gear, and it's auto.

Rochester

iTrader: (3)

I don't have NmexMAX's credibility, nor mechanical aptitude. Just a daily driver with insights that come with age.