Colonel

My guess is that they have no idea how long it takes. If people know what they are doing, it should not take long. Its like installing a program on a computer. I know when they do mine, I will be watching like a hawk. EPROMs don't take long to burn. Not unless stuff is being replaced....Just my opinion though.

y2kse

iTrader: (1)

My observations are along the lines of those posted by max2001se. To make a long story short, the ECM upgrade is WELL worth the time and effort it takes to have it done. My car has gone from "undriveable" to "driveable" in 1st gear at low rpms. What more can I say?

One quick heads up. My dealer's first attempt at reprogramming the ECM failed. The reason, according to my dealer's lead tech, is because the ECM has to be reset electronically before the upgrade is applied. That tiny factoid is missing from the TSB!

Green 2kSE

y2kse, how long did the dealer take to fix your car? Thanks.

IceY2K1

iTrader: (3)

What about the on/off power surging around 2500rmps or really between 2K-3K rpms? Any better?????

nisMAXse

I agree...can the TSB be re-scanned and re-posted please? Perhaps it's hosted on someone else's site...?? When I print it out (at least on my printer), some of the sentences are cut off as well. Thanks for any help on this.

ohboiya

iTrader: (3)

i have an appt 2 have it done & the service tech said it should take no longer than an hour

y2kse

iTrader: (1)

It takes about an hour to do the upgrade, Green 2KSE. But if you've got a tech who really knows what he's doing, a half hour is all he'll need.

I'd be happy to e-mail the TSB to anyone who wants to host it. It's not going to get any clearer though because it's a faxed copy. Keep in mind that all you really need is the TSB number (NTB01-018). The dealer can look it up for themselves (it's on their latest Tech CD) or they can call the Nissan-USA tech line for confirmation.

BTW, if your dealer says they can't find the TSB or that it doesn't exist, let me know. We'll have a field day with them.

IceY2K1

iTrader: (3)

How is the surging between 2000 and 3000 rpms? Especially, right about 2400 rpms in 4th and 5th gear.

y2kse

iTrader: (1)

I haven't noticed much difference one way or the other.

jayc5627

iTrader: (1)

Hey Kev,
so can I tell them to upgrade my TCM.
I also have an auto. The TSB that's shown here is for manual, would they buy it???

IceY2K1

iTrader: (3)

1)So, basically the ONLY difference you can tell is the tendency to buck in 1st gear has been eliminated?

2)Anything else like loss of throttle response?

3)What about the ability to hold 2500 rpms in neutral without it jumping up to 3000 or dropping below 2000?

4)When you push in the clutch does it increase in rpms still or does it hold at that rpm for 1-2 seconds before dropping?

y2kse

iTrader: (1)

1) Not eliminated, reduced.

2) No.

3) No discernable effect.

4) No discernable effect.

davedzny

Here's a copy of a post I just sent on the Edmunds board:

I had the TSB done today on my car. Of course the delership had no clue. Fortunately I know a mechanic there and he knows I used to also be a mechanic, so he takes care of me. He had to update their software so they could print out the bulletin and load it into the Consult since it wasn't in their system yet. Unfortunately he was busy doing another job so they gave my car to some idiot who didn't have a clue. About four hours later the SM comes back and says they didn't find anything wrong. I then gave him a copy of the TSB and said "do this". Morons. I expected this, and fortunately we all know about the TSB.

Since I have been very vocal about this issue, let me give you my first impressions after having the reprogram. I will find out more information as I drive the car day to day in traffic, but here's what I found during testing today:

1) RPM test from 3000 down to idle in neutral still fails; the engine cuts the fuel @ 2500 RPM when you are trying to slow down the engine in neutral. No change from before TSB.
2) You can hold the car at a steady 1600 or 2100 RPM in neutral while stopped; if you try to hold it anywhere between 1600-2100 (i.e. 1800 RPM or so), the engine will continue to rise in RPM up to 2100 with NO change to the gas pedal.
3) Starting from a dead stop seems smoother to me; gas pedal seems easier to control and not so touchy off idle.
4) Idle RPM seems to be around 800.
5) Engine still does not slow down and compression brake when gas pedal is released while cruising (i.e. driving 40 MPH 4th gear @ 2000 RPM and let go of gas completely causes RPM to stay stuck at 2000 for about 5-10 seconds before decreasing).
6) Normal speed upshifts at around 2500 RPM - RPM's are still held when clutch is depressed, but are dropped very fast (about 1500 RPM) when clutch is released - slightly improved as the RPM's only hang during the disengaging of the clutch now.
7) Fast upshifts (pressing clutch in and out as fast as you can) at 2500 RPM still cause RPM's to rise when you slam the clutch to the floor as quick as you can.
8) When pressing the clutch and brake together as you come to a stop, the RPM's are held at 1000 all the way until the car stops; then they slowly return to idle in about 5 seconds (Possible reading VSS for this? Emissions control once again I presume on deceleration.)
9) When stopping and slowing down without pressing the clutch, RPM's drop to idle (engine still loaded, computer is not artificially holding RPM's up for emissions I think.)
10) "Racing" shifting (i.e. shifting at 4000 RPM and higher) improvement; RPM's decrease instantly as you press in the clutch. This is how it should be at all speeds, though. They are still holding the throttle open at lower RPM shifting since that is the majority of shift instances.
11) 1st gear test 1500 - 2000 RPM. Car seemed steadier, I did not experience any fuel cut in the 5 minutes or so testing I did. I will find out more when stuck in traffic.

Hope this post helps. Nissan still seems to be programming the ECM to help decrease emissions by artificially controlling the throttle, which is very annoying to a driver who drives stick and is used to having full control over the engine's throttle. I will give more feedback on this TSB as I do more driving. For right now, I feel if you have noticed any bucking in 1st gear, get it done. It didn't seem to make things worse. If you have had no complaints about the fuel cut, then maybe you want to leave "well enough alone".

Dave Z

IceY2K1

iTrader: (3)

Thanks for the reply guys! I guess I hoped for more improvement in the 2000-3000 rpm range. I'm not sure if I will get the "upgrade"(ha!), since I don't drive in stop-and-go traffice much and that seems to be all that the TSB seems to improve. However, please keep me posted if you notice ANYTHING else good/bad. Thanks again!

Bigk200

I mostly hang out at the Edmunds board.

The TSB that you all are getting is the same one that I got 15 months ago. I guess it took them a little while to put it on the CD.

All of your observations are the same that I had after they did my car. The problem is, it still doesn't fix the problem. In fact, it almost makes the problem worse in higher gears such as 3rd gear at 40 mph.

Until Nissan implements a fix that will pass the stationary test, it isn't really fixed.

Omegasrk

iTrader: (1)

For this TSB, do I need to put back the orginal intake or would the Stillen Hi-Flow would suffice? My car does show this problem and I want to get it properly fixed.

y2kse

iTrader: (1)

Your intake doesn't make any difference. If you're concerned about the dealer threatening to void your warranty, however, put the stock airbox back on before you take your car in for the ECM upgrade.

maxleaner

Does anyone know what control device is used for the computer to override manual input of the throttle? I'm assuming the connection to the gas pedal is still a spring loaded cable (at least I see that in the engine bay). If not, this idea is sunk. If there is some kind of actuator or solenoid the computer can use to override the throttle cable, I wonder if it can be disconnected without upsetting OBD II...I imagine it would if there is some kind of subroutine that compares output of throttle position sensor with input of "throttle override solenoid" (my made up term)to make sure the device is working.

If computer handles override by also controlling the fuel supply, there might also be a problem, unless that's run off the output of the TPS rather than the override mechanism.

Any thoughts?

y2kse

iTrader: (1)

There is NO-ONE inside or outside of Nissan who knows more about the fuel-cut condition than Bigk200. I'd suggest you send him an e-mail and run your question by him.

Bigk200

The 2K Maxima is designed to accelerate aggressively with only a slight movement of the gas pedal. The way that Nissan achieves this is by simultaneously dumping a huge amount of auxiliary air into the engine via the idle control valve. Nissan Engineers probably did this to “wind up” the automatic transmission torque converter as quickly as possible in order to make the car very quick off the line.

The aggressiveness of this air dump is VERY new to the 2000 Maxima design. In fact, the entire intake system (including the idle control valve) is different from the 1999 model. In addition, the ECM was redesigned for year 2000.

The large amount of air that is dumped into the engine via the idle control valve is not a huge problem at first, except that it’s possible to run over a pedestrian. However, the extra air ends up being a problem when slowing down because the idle control valve is not subsequently closed as the gas pedal is released.

The “fuel-cut” scenario goes like this:

The driver steps on the gas to accelerate, and the idle control valve opens to assist with the acceleration. The increased voltage on the TPS (throttle position sensor) provides an “advance notice” to the computer to expect additional air. This expected additional air is then matched with additional fuel from the injectors. The computer then watches the mass air flow sensor signal to verify that the additional air really did arrive, and if a major discrepancy is detected between the TPS signal and the mass air flow sensor, the check engine light will be illuminated. Ultimately, the mass air flow sensor (and exhaust sensors to some extent) have final control over the amount of fuel that is injected into the engine. The TPS only provides “advance warning” to the computer and does not ultimately control this process.

And so, after the engine has accelerated and the car is traveling at some higher speed, the driver will eventually want to slow down. The most obvious way to do this is to just ease off the gas pedal. However, as the driver attempts to deprive the engine of air by releasing the gas pedal, the engine continues to acquire large quantities of air from the idle control valve. (Remember... I said earlier that the idle control valve remains open even as the gas pedal is released). Because the mass air flow sensor has the final say in how much fuel is injected into the engine, and because the engine continues to receive air through the idle control valve, the engine continues to produce more power than is desired. Finally, when the gas pedal reaches the end of its travel, the TPS outputs a “throttle closed” voltage and the computer subsequently cuts fuel. This is the “fuel-cut” phenomenon that so many have complained about.

Thus, the engine cycles from producing a fairly significant amount of power to producing NEGATIVE power in the fuel-cut mode. The word “negative” is used because the engine is compression braking during the “fuel-cut” mode. There is no in-between... it either produces too much power or negative power.

And now back to the sequence off events:

While the “fuel-cut” condition is in effect, the engine provides maximum compression braking. It is also operating at maximum vacuum... which means that it is sucking as much air as possible through the idle control valve. However, as long as the TPS is outputing a “throttle closed” position, the “fuel-cut” mode remains in effect.

If at some point during the “fuel-cut” mode the driver decides to speed up, the TPS will subsequently stop outputting the “throttle closed” voltage and the computer will begin providing fuel to the engine. Because the idle control valve has remained open during the entire “fuel-cut” period, and because the mass air flow sensor has continued to see air flowing into the engine, the computer calls for a large amount of fuel to match the air that is flowing into the engine. Thus, the car will get a much more robust punch of power than was expected. Sometimes this surprising acceleration will cause the driver to quickly let off the gas, only to be subjected to an immediate “fuel-cut” again. Thus, a vicious cycle can occur during low speed driving... lurch (accelerate) forward... hard compression braking... lurch forward... hard compression braking... etc.

Excessive air from the idle control valve is also the cause of rising engine rpm’s between shift changes. A small delay is designed into the ECM prior to issuing a “fuel-cut”, and as the engine continues to acquire air through the idle control valve during shifts, the computer matches this air with fuel. Thus, the unloaded engine rpm’s will float up about 400-500 rpm during each shift change.

And so, the engine cycles continually between too much power and too little power with no ability to feather the throttle up and down at minimal outputs of power. This cycle repeats itself over and over and over and over again... until the driver is stark raving crazy. To further enhance the drivers emotional torture, Nissan Engineers and zone reps routinely tell owners (with a straight face) that the car is perfect and “it is all in the drivers head”.

The “fuel-cut” problem manifests itself in several
ways:

1.) An engine that lurches between no power and
too much power while operating with cruise control.

2.) An uncontrollable throttle on 5-speed models,
making the car lurch badly at low speeds and
annoyingly at higher speeds.

3.) Rising engine rpm’s between shifts on the
5-speed models.

4.) Unsafe/uncontrollable accelerations when
starting out, which can cause a collision with
another vehicle, or possibly with a pedestrian.

For those who want to argue that this is normal, and was done because of emissions, let me point out that emissions laws are the same for year 1999 and 2000. This driveability problem has only surfaced with the 2000 model. Furthermore, other manufacturers have not resorted to such high flows of air and fuel to achieve compliance with emissions laws (except maybe Ford, but I used to believe that Nissan was better than Ford), so why should the Maxima be unique in that regard?

Also, for those who want to argue that only a few Maximas have the “fuel-cut” problem, and it must be due to a faulty component, I would have to disagree. I have yet to find a 2000 Maxima that passes the stationary test (trying to ease rpm’s from 3,000 rpm to 2,000 rpm). They all fail this test (both 5-speeds and automatics) because of the idle control valve. The only real difference from one car to the next is the driver. Some slight differences probably exist from car to car, but the biggest variable has to be the driver.

For those who think there must be a faulty component, then here is a list of the candidates: Idle Control Valve, Throttle Position Sensor, Absolute Pressure Sensor, Front and Rear Oxygen sensor, VIAS system, Mass Air Flow Sensor, Intake Air Temperature Sensor, Coolant temperature Sensor, EGR system, and EVAP system. Go ahead and check them all out, but you will find all of them to be in good working order. It is the ECM's control of the idle control valve that is the REAL problem.

In summary, the 2K Maxima engine has been optimized for the automatic transmission with little or no thought given to its compatibility with a manual transmission. The 2K Maxima 5-speed needs to have its own engine control software rather than shared software with the automatic models. The idle control valve needs to be closed as the gas pedal is released. Furthermore, the idle control valve does not need to be opened so severely when accelerating from idle speed.

maxleaner

Thanks BigK. That is helpful information. This answer should go in the FAQ (if it isn't already there).

I'm in total agreement with your opinions. Manual transmission enthusiasts in the US are getting the short stick everywhere. Well equipped 6 cyl sport sedans for 30K or less with manuals are essentially down to 2 as others abandon manual trannies altogether - and now Nissan is half-a**ing it.

There might be ways we could override the system and fake out the sensors to avoid the check engine light, but we shouldn't have to do it. I suspect with the new Altima and an all new Max a short time away, the 2000-2002 issues will hit the back burner; and we will have to hope some aftermarket company comes out with a reprogrammed ECU for manual transmission enthusiasts. The only drawback is we'll have to pay another $400 to make our cars driveable the way they were supposed to be in the first place.

When I test drove the car, I thought all the jerking was my newbie foot getting used the the ultra light springs on the gas and clutch (comparing it to a 95 Prelude VTEC). Now that I've driven it a month, I know better.

For now, I'm not even going to bother with the current TSB. My main annoyance has been when coasting/feathering the throttle at highway speeds keeping up with traffic, going down slight grades, etc. This is above 1800 rpm most of the time, so this TSB does nothing for me. I have noticed the annoyance in parking lots, traffic jams and the like, but I solve them by disengaging the clutch and coasting that way (STILL not really the way it's supposed to work).

y2kse

iTrader: (1)

And definitely harder than necessary on your clutch components.

freeze2k2

is this something nissan has put in as a factory recall? I went to the pathetic excuse for a dealer in poco today, and he ran my vin #. After nothing came up, he told me there was nothing he could do. He also scoffed at me when he found out i got this info off the net, what a moron. P.S. he should also trim them long hanigin nose hairs. My god what a mess.

y2kse

iTrader: (1)

Nope. This is a Nissan Service Bulletin. The Service Bulletin number is NTB01-018. Call your dealer and tell them to look it up. If they refuse, open a case with Nissan-USA (1-800-NISSAN1). Tell them your dealer is refusing to honor your request for service under that Service Bulletin. That should get the job done.

freeze2k2

y2kse, dont forget im in canada, so im dealing with nissan canada eh.

y2kse

iTrader: (1)

Good point. I'm not certain if the TSB applies to Canadian Maximas or not. I'd suggest you send your e-mail address to me at bld522@yahoo.com and I'll attach a scanned copy of the Service Bulletin to a reply. Then print out the bulletin and take it into your dealer.

opimax

and Fed emissioned cars as far as the fuel cut goes? I ridden in a few 2Ks and of all of them mine was the worst. I suspect something else additionally but the dreaded "NTF" and no acknowledge that their is a fuel cut problem to begin with. I checked today and found out I have a CA car even though I am on the other coast. HI Kevin, any thoughts on this? did you notice it when you looked at my car? Also, anybody, should I be concerned that I have CA car or is it normal? what differences are there?

Thanks,

Mark

y2kse

iTrader: (1)

The ECM part numbers are different. But the TSB applies to all 2001-2001 M/T Maximas regardless of whether they're Fed-spec or CA-spec.

ohboiya

iTrader: (3)

but I would also luv a copy 2 print out ... can u e-mail me as well?

eugene.lee@utoronto.ca

y2kse

iTrader: (1)

Check your e-mail.

ohboiya

iTrader: (3)

grazie!

davedzny

After driving my car for a few days, I have found some other behaviors now being exhibited by the car after having the TSB performed. I posted a lengthy summary earlier in this thread about how my car performed after the TSB was performed. Now I'll add my newest observations for all to see/compare.

I have observed that the lurching/fuel cut is still present in 1st gear. However, it now happens at 2000 RPM instead of at 1500 RPM. I also don't like how the car stays at 1000 RPM with your foot off the gas while coasting in traffic in 1st gear. My car used to stay at idle at around 700 RPM under these conditions before the TSB was performed. The only good part of the TSB was to help eliminate the bucking @ 1500 RPM, which is now replaced with the bucking @ 2000 RPM. I find myself in 1st gear at 1500 RPM more often then 2000 RPM, so it makes it somewhat better. However, if this is still felt in higher gears at this engine speed, people with complaints of the fuel cut with the cruise control on might still have problems. I never use my cruise control, so I can't perform that test to see. This TSB is not a "fix" or "cure", but simply a band aid.

Dave Z

y2kse

iTrader: (1)

I agree it's a band aid, Dave. But it certainly makes driving my Maxima much more manageable in bumper-to-bumper traffic. And given the probability that this is the last we're going to hear from Nissan on the subject, I'm prepared to live with it.

IceY2K1

iTrader: (3)

Thanks for the update. I too figured this might be just a "band aid" and that's why I've held off to see how more peoples experience turns out. Thanks again and good luck!

y2kse

iTrader: (1)

It depends largely on the kind of driving you do, IceY2K1. I live in Los Angeles.

Any questions?

MS 2K1 AE

Sorry for joining this thread so late...I just purchased my 2k1 AE (March 22nd) and this is my first post (I've spent the past two days pouring over all the threads here).

After 6 months of fact finding, I decided not to buy my fourth Accord and go with the Max. I wanted the six and the five speed. The AE LSD made the decision even more simple. After searching high and low, I came across an exceptionally friendly dealer with 3 AE 5 speeds coming in the next day. I show up at 9am and watch them unload the truck. Two were loaded and one was a rare AE with cloth interior and BOSE (I'm not a big leather fan). Two hours and 3K off sticker, I'm on my way home.

Even on that first trip, I noticed the "bucking." I thought that it was just 12 years of driving 100-135HP Accords and that I needed to get used to controlling 227HP. It looks like it wasn't me after all. I tried the test Adam01GXE described earlier in the thread and he was right.

I'm calling the dealer ASAP to see just how friendly they now that I have the title. Thanks for a great site and thanks for the great info.

Bigk200

..

martinf

I am leaving for the dealer in the next 15 minutes to have the TSB done. I expect them to mess it up. Funny thing, but as the weather is warming my car bucks less in 1st gear.
Either that, or I am compensating by accelerating differently.

Bigk200

The most likely reason for your observation is that when the weather is warm, you are running the airconditioner. The airconditioner places a small load on what would otherwise be an unloaded engine.

martinf

Nope, havn't used the A/C