Maxima 5-speed Problems

joenissan

You may want to have him also check the other TSB's I gave you as well. They seem to all have something to do with either an idle problem. Just so nothing is missed.

Joe

bigk200

Did you show the service rep my findings in post #2? If not, it would be great if you would give him a copy.

bigk200

Joenissan, your service rep. said the following:

"The drop in RPM between 3100 and approx. 1500, is
done by the TPS, not the ICV, and is not a
"glitch" (as he put it). It has something to do
with the variable intake which, so it seems, opens
to a short runner about the 3100 RPM mark."

I thought about what this for a while and read up on the VIAS in the service manual. I also did a little experimentation and I am certain that the VIAS is not responsible for the "fuel-cut" driveability problem.

For one thing, the VIAS opens and closes at rpms above 3100. The stationary test alone shows that the fuel cut seems to be a problem in the mid 2000's. (When testing the VIAS, the service manual requires that the engine be operated at 5000 rpm, at which point the VIAS is supposed to have opened. Maybe 5000 rpm is recommended just to be certain that the valve will be fully open.)

Second, I actually disconnected the wires that attach to the VIAS control solenoid valve, and then drove the car. There was NO difference in the cars driveability. I also did the stationary test, and there was no difference. With this connector disconnected, it is impossible for the VIAS to open and close, and it must remain in the closed position. This test is easy to do if anyone else wants to try it. The control solenoid is located on the right (drivers side) end of the intake manifold and is black in color. The control solenoid can be recognized because it has a vacuum hose attached to its front face and the black connector is directly below it. (I can send a digital picture by email if anyone wants a visual of it.)

Third, there is only one path through which air can enter the engine (excluding the EVAP system which I have also checked out). The air either has to pass by the butterfly valve which is controlled by the gas pedal, or it has to pass through the idle control valve. There is no other path available. At the instant that the fuel-cut occurs at "closed-idle" on the TPS (ie the butterfly valve has reached a closed position), the engine is still producing too much power (ie. air is still entering the engine). If the butterfly valve is closed but the engine is still acquiring air, then air has to be entering the engine from the only other path that is available, which is the idle control valve.

I don't need to bore everyone with these details for a second time. For a full and more thorough explaination, just re-read my post #2 in this thread.

Therefore, I do not believe that the VIAS is responsible for the fuel-cut driveability problem and I stand by my original findings in post #2.

It is frustating that Nissan does not fully understand the fuel-cut problem. If they don't understand it, then they certainly can't fix it.

joenissan

yes...I gave him a copy as I said I would. Keep in mind though Big, he's not claiming it's the variable intake. He's claiming it's the ECU, and it's programming being the way it is, has something to do with the Variable intake. You're disconnecting the "VIAS" isn't going to change the ECU's programming. So if the ECU is programmed to "cut the fuel", it's going to do so reguardless of your disconnecting anything.....Don't you think ?

Joe

joenissan

I would ask you to do me a favor. And if you wouldn't mind, E-mailing the info to me so we don't bore the rest of the gang.
I did read your #2 post in detail, I'm just not sure yet if I understand exactly what the car is doing from a seat of the pants point of view, as well as when it happends, at what speeds, what gear(s). My experience is that it feels like a harsh driveline lash, and only in 1st gear. Now THAT I've felt myself, but never in any other gear, and only at very very low speeds. The fact that the car won't pass a 3000RPM to 2000RPM really means nothing as far as drivability goes.
I'm sorry to make you go through it again but, I feel I really have to understand the "problem" fully in order to be able to explain it with any oomph. Maybe I've just driven too many to even notice it.
I'd appreciate your E mail...Thanks, and again, I apologize for beating a dead horse.

Joe Joenissan@aol.com

bigk200

Its late and I'll be out of town until Sunday, but let me try to explain the most important point that will help you to understand things better.

(I think I'll post here for the benefit of others.)

The "fuel-cut" at closed-throttle is not THE problem. I think we are all in agreement on that. What is important to note is that it is a SYMPTOM of the REAL problem.

The REAL problem is that an unloaded 2000 Maxima Engine will not willingly slow down as the gas pedal is released. As the driver eases off the gas pedal, the engine continues to produce more power than desired, and the engine never slows appreciably until the "closed throttle" position is reached on the TPS. (Remember, at closed-throttle, the fuel-cut event occurs.)

Digging a little deeper... The reason that the engine will not slow down is because it continues to receive AIR (and fuel) even when the butterfly valve is nearly closed. At the very instant when the butterfly valve is on the verge of reaching a "closed" position, the engine is producing a lot of power with air that is being acquired from the idle control valve.

Therefore, the REAL REAL REAL problem is that the idle control valve allows too much auxillary air into the engine, independent of the butterfly valve.

The net result is that the car cannot be slowed by easing off of the gas pedal. Instead, it continues to produce power right up to the very instant when the closed-throttle "fuel-cut" event occurs, at which point the car will suddenly compression brake without a smooth transition from "power" to "fuel-cut".

bigk200

I wish I had never coined the phrase "fuel-cut". If I had it to do it over again, I would name it an "Uncontrollable-Throttle".

That would have been much more appropriate and less confusing for the Nissan techs. The "fuel-cut" title implys that the closed-throttle fuel-cut event is to blame, but it is only a SYMPTOM of the REAL problem.

bigk200

If the 2000 Maxima engine would willingly slow down when easing off the gas pedal, then the closed-throttle "fuel-cut" event would be hardly noticeable!

There it is in a nutshell.

kostya

Could you please e-mail me some additional info on idle control valve (if you have any)? Did you try to measure the voltages in/out? disassemble it?

My e-mail is mh3023@hotmail.com

Thanks.

bigk200

I'll catch you at the end of the weekend. Gotta leave now.

y2kse

Count me in. Find out how many others want to participate and we'll split the cost evenly. Right now with you, Kevin and me, the cost would be about $20.00 each. But if others join us, the cost will go down even further.

Anybody else want to join in? Dave Z? Warren?

Bruce...

opimax

Just got done changing oil and boom, count my check in..

Mark

davedzny

Guys, you can count me in for help/funds. If we do this, such things as the design, hosting, and upkeep will have to be discussed for the site. I'm gonna call up my Nissan rep on Monday and try to speak to the most senior person there. I might also see if I can negotiate a buyback from them, but what else am I gonna drive?

I passed by a BMW dealership to look at the new 3 series. Very nice, and the 330 has 225 HP and 0-60 in 6.4 sec. Too expensive for my blood though unfortunately. I didn't test drive one yet, but I know their whole throttle control system is done electronically. It might even by "throttle by wire", but I'm not sure. BTW, all 2001 BMW models are spoken for. In order to get a car, it has to be factory ordered with a 2 month waiting period. Guess BMW has no problem selling their cars.

Dave Z

joenissan

I know SOMEONE must have something to say....lol

bigk200

I'm waiting to see if you can get any more info from your zone rep.!

I still believe that the idle control valve is letting too much air into the engine, independent of the butterfly valve.

Maybe you can "yank his ear" again on this issue.

y2kse

I'm also waiting for my zone rep to get in touch with me.

And waiting . . . and waiting . . . and waiting . . .

davedzny

I'm waiting also.... called up my rep today and left a message basically saying that at this point I want a new car. I said I can go through arbitration or lemon law, but the lemon law will either give me money back or another car anyway, and I am quite confident I will win. In NY, if they can't fix the car after 4 tries for a defect that affects the value of the car, then you can lemon law it. I have videotape evidence of my car and others, and can most likely get another car to use at a hearing to prove my defects.

I had a chance to do the neutral test on 3 other 2000 5 speeds and one 2001 5 speed this weekend. Each car dropped to 1500 RPM convincing me that my drop to idle has to be related to the severity of my problems. I can use that in any judgements with Nissan, and maybe I have a defective IAC and/or ECM that is causing the drop to idle. I won't let them try to replace either part at this time, though.

I know all the cars will have the idle motor problem in regards to the excessive air intake, but I have a strong feeling that the neutral test on cars that stop @ 1500 RPM might help to mask the problem a little more. I told my rep about this as well on the message, and also said that the Nissan engineers have no idea what they are doing and how they have to look at the idle valve and how this is a safety issue since you effectively cannot control the throttle of the car.

The 2001 model was real nice. I liked the new rear view mirror and the steering wheel radio controls. I don't think it is possible to hook up the radio controls to a 2000 MY. You would probably have to get the controls, a different clock spring for the steering wheel with wiring for the controls on its printed circuit board, harness to the radio, etc and that would be expensive. If I could get a 2001 model out of Nissan, I would be happier, but not satisfied.

I think I have a true "lemon" or a Friday afternoon produced car since besides the fuel cut, I also have multiple rattles (even with a-pillar foam), horrendous rear bumper paint scratches (that even extend below the trunk lid surface!), and whine from blower motor with 4400 miles on the car so far. Seems like most of the TSB's relate to my car.

A car is just a machine, so there will be defective ones out there, and I think I have one unfortunately. It sucks that I have a lemon, but what really gets me is Nissan's attitude that I have received from their salespeople to the service managers to the engineers and the corporate people.

I might be used to excellent customer service since I was a tech @ Saturn for a while, but Nissan is truly at the bottom in regards to customer service. I'll keep everyone informed with my progress, but I am in full "fighting mode" now.... lol

BTW Joe, is Carlos your District Rep? He should remember my car if so.

Dave Z

joenissan

Dave...no..his name is Dale, never did know his last name though. BTW, check the full lemon law...I believe the car has to be undrivable for a certain period of time, and you CANNOT refuse to have them replace anything having to do with your problem but...I hope you make out ok. Not all Nissan service sucks though....sounds like the few I've read about in here need to go elsewhere. BIG....The info I gave is all he knows about ...so far. Reguardless of what part is acually causing this "problem", it's the ECU that's controlling it. That's all I have to date.
and....if I'm understanding this right...the problem is causing an "uncontrollable throttle", meaning when you let off the gas (at low speeds in low gear(s), the car will not slow down ? I myself, after reading what you wrote, tried this while paying attention to the engine braking. I didn't feel or experience any such thing...i do feel the sharp on-off throttle responce... though haven't found it to be of any problem. Again remember...I may just be so damn used to it that it may seem normal to me but...that's what I've found.

Joe

opimax

I believe this is the point between "good working" and "poor working" cars, is this correct? My question to Joe would be does nissan acknowledge that there is a difference between the 2, one stopping @ 1500 and the other strait to 600 on the idle test and to note that the cars do drive very different? or is this not an "accepted" notation and that doesn't matter? Kevin, I don't remember if we talked about this difference when i saw you, can this be explained? does this have any signifigance to which cars are in need of a ECU exchange?

Thanks guys,

Mark

joenissan

I'm not sure I get what you mean. Down to 1500 or 600 ?

Joe

bigk200

Before Nissan did their "fix" on my car, I could also get it to hold at 1500 rpm on the neutral test. After the "fix", I think it drops down to idle, but I'm not sure. I haven't done it for a while.

Even so, I was just as unhappy with the way the car drove before AND after their "fix". I my opinion, the difference that Davedzny is concerned about (ie. some cars drop to 1500 rpm and others drop to idle during the test) is not particularly relevant to the main problem (which is the idle control valve). However, I do not dispute that this difference might make Dave's car a little worse than others.

I don't think Nissan service is as bad as Nissan-USA technical support. The service people can fix defective parts & adjustments, but they can't re-Engineer everything. If Nissan-USA is unwilling to communicate problems back to Japan, then there isn't much the service departments can do.

bigk200

You wrote:

"if I'm understanding this right... the problem is causing an "uncontrollable throttle", meaning when you let off the gas (at low speeds in low gear(s), the car will not slow down ? I myself, after reading what you wrote, tried this while paying attention to the engine braking. I didn't feel or experience any such thing...i do feel the sharp on-off throttle responce... though haven't found it to be of any problem. Again remember... I may just be so damn used to it that it may seem normal to me but...that's what I've found."

That sharp on-off throttle response that you feel is the fuel-cut that we are all complaining about. The reason that it is so sharp is that the engine does not slow down much when you let off the gas, but once the "closed-throttle" position is reached, the drop-off in throttle response is dramatic.

When I drove the BMW 528 5-speed (2) weeks ago, it was apparant that BMW had managed the closed-throttle event much better. If the BMW has a closed throttle "fuel-cut", then it is very very hard to notice.

If Nissan would cut down on the auxillary air entering the engine from the idle control valve, then the closed-throttle "fuel-cut" would be much less abrupt. I personally don't think the "fuel-cut" is such a great idea on a 5-speed, but it could at least be made much less abrupt.

bigk200

When performing the stationary test (3000 downto
2000 rpm while in neutral with no external loads),
some cars drop to idle when 2500 rpm is reached and some cars will drop to 1500 rpm and kind of hold there for a little bit.

I think this is mostly a small difference in the
TPS adjustment from one car to the next, but I
don't believe that it is indicative of the main
problem, which is excess air from the idle control
valve. However, maybe it does make Davedzny's car
worse than others.

kostya

Bigk200: Thanks for the data on the idle valve.

From the info you provided I bet a stepper motor operates the valve. The nice feature of this type of motors is that they tend to stay in the same position even after the power was disconnected.

Thus there is a patch to the uncontrollable throttle problem. All we need is a circuit that sniffs the TPS and activates the relay that simply cuts off the power from the stepper motor.

I view the scenario of the operation as the following:
· Starting the engine: accelerator is released, TPS sends 0, our circuit “enables” idle valve, so the engine can have appropriate idle RPM.
· Cruising: as soon as you press the accelerator, TPS outputs whatever nonzero value it has; our circuit reads it and disconnects the stepper motor thru the relay. Now we’re in control of the engine.
· Parking: as accelerator is released TPS sends a zero signal, our circuit reads it and “enables” the idle valve. Now ECU controls the engine RPM and increases/decreases the air flow as necessary.

That’s how I see it. It’s late here in CA now; I’ll try to work on schematics for the sensing circuit tomorrow. Bigk200, what do you think? Maybe we should patent it before NISSAN does?

bigk200

It sounds simple but could become a headache to execute. We can talk later... I gotta run for now.

davedzny

I'm not sure the type of modification discussed here will work. As I remember, the IAC is supposed to open up and let in more air when you are accelerating or on the gas pedal and I believe if the computer senses a rich signal from the O2 sensor it will try to lean it out by closing up the IAC and decreasing injector pulse width, thereby reducing excessive air/fuel to lean out the ratio. When the computer senses a lean condition from the O2, it will do the opposite with the IAC and injector pulse.

I also think if the computer sees a low temp from the coolant temp switch it will also open the IAC for more air to richen the mixture and vice versa with a hot to very hot engine. The IAC also kicks in when there are loads on the motor (i.e. A/C, headlights, power steering stops, etc.) The whole reason we have computers controlling the engines today instead of carburetors is that a computer can keep the engine in that window of the "perfect" 14.7:1 air/fuel ratio that minimizes emissions much better then a carburetor could.

Note also that the rear O2 sensors are there to check the job that the front O2 sensors are doing. I believe the rear O2 should remain at around .500mv or less thus indicating that there is little to no unburned fuel left in the exhaust.

It has been a while since I hooked up my old Snap On scanner to a GM or something where you can monitor all of these readings and see the changes take place live, but I am pretty sure my memory holds up on the fact that the IAC is designed to be an actively controlled unit throughout the whole driving range so I don't think it is possible to program it to be an "on/off" type of actuator. I used to be heavily into all of that computer controlled stuff when I was an auto tech. Guess that's why I'm a network admin now....

Dave Z

y2kse

from my Zone Rep. I described the fuel-cut condition to him. He's going to meet me around November 1st to test drive my vehicle. In the interim, he said he would test drive a couple of other 2K Maxima 5-speeds to see if they exhibited the fuel-cut condition.

I e-mailed my Zone Rep the URL for this forum. I specifically asked him to review Post #2 and the other posts from bigk200.

My Zone Rep treated me courteously and professionally. I told him that, unlike some, I could live with the fuel cut condition whether or not it ever got fixed. He said he appreciated my attitude, but that his job was to pursue these types of issues to their logical conclusion in order to make the Maxima a better driving car.

Stay tuned.

Bruce...

davedzny

Bruce, do you know the name of your zone rep? I want to mention the names of your rep and Joe's to my Nissan Customer Service rep to show that I know I am not the only one with this problem. TIA.

Dave Z

y2kse

His name is Stephen Thomas, Dave.

y2kse

What's your Zone Rep's name?

joenissan

I understand now.....But I only notice the sharp off throttle lag in 1st gear...no other gear has that problem. And I read what you said about the car not slowing (engine braking) when the throttle is lifted, ( I assume you mean in any gear), mine does slow down properly in every gear except for the harsh slowing in 1st gear throttle off conditions.

Joe

bigk200

Anytime you are just trying to maintain speed on a mostly flat or slightly down hill road, the unwillingness of the engine to slow down becomes a problem. In that situation, the engine continues to produce too much power until the closed-throttle "fuel-cut" event occurs.

If you want to drive a 5-speed that doesn't have this problem, then check out the BMW's. I also know for sure that Maxima's from the late 80's did not have this problem. I don't know at what point in the 90's that Nissan implemented the closed-throttle "fuel-cut", but it is most problematic on the 2000 model.

(The "fuel-cut" feature was probably implemented with OBD II)

joenissan

As I've noted before...I owned a 95 325, and have driven a neighbor/friends 95 530 V8 5 spd many times (even test drove the new 330i) so I know how they drive and feel. In the Maxima,other than 1st gear, I don't notice any problem at all, and I'm not in 1st gear long enough, nor am I traveling a 2 or 3 MPH in 1st gear to even notice it. If your car is "bucking" (for a lack of a better word), in any gear other than 1st, then that's a problem...one my car doesn't show any signs of.

Joe

bigk200

With all due respect, I do not think that you are particularly sensitive to the fuel cut problem.

Perhaps you are one of those drivers who are "all on" and "all off" of the gas pedal? Or perhaps you clutch quickly rather than slowing the car with the gas pedal?

(Most drivers who are "all on" and "all off" the gas pedal will never admit that they drive that way.)

If your car is so great and and other cars are so bad, then why can't Nissan make all cars perfect like yours??? Nissan appears to be fortunate that many owners are too apathetic to complain and many others don't know any better.

Just as you noted in an earlier post, your very own service rep. said "THEY HAD RECEIVED HUNDREDS OF COMPLAINTS ABOUT THIS". I think that statement alone provides vindication for anyone who is concerned about the "fuel-cut" problem.

davedzny

Bruce, my DTR's name is Carlos. I have to find out his last name. I speak with Carol Miller, who is handling my case @ Nissan and can give you her phone number if you want. She is the team leader of the "follow-up group". I love these titles people get... lol

Dave Z

y2kse

E-mail the info to me if that's more comfortable for you. I'll pass it on to my Zone Rep. My e-mail address is bld522@pacbell.net.

Bruce...

joenissan

You may have hit it right on the head! I am kind of a lead-foot, and I'm probably not sensitive to the fuel cut problem. That does NOT mean one doesn't exist, and I am NOT insinuating any such thing. My questions were only to fully understand the complaint...that's all.
I'm sure all those folks complaining of the same thing aren't nuts...lol. I just wish I could experience it for myself. I drive 53 miles each way to work every day. I'd say about 40 of them (each way) are highway, that's 80 miles a day at steady speeds (some even with cruise on) and I've yet to experience as much as a hiccup from the car. By the way....I've not had oneone yet come to our dealer with that complaint yet. Maybe then, I'll understand.

Joe

davedzny

The following is part of a post from www.maxima.org 5th gen Max board. I am thinking about emailing the author of this post and see if he is willing to let us use his testimony of the following incident.

The post is from a 5 speed problem thread that has just started there. Of course I added a bunch of info there, but most people on that board are die hard Maxima enthusiasts and refuse to hear any negative comments related to a Maxima. Here is the quote from the post:

"As for the full throttle thing, I dont know. I do know that I went to inch up and my car took off about 5 feet and hit a pedestrian. I was taken totally by surprise. yeah, felt like a total idiot and luckly I didnt hurt him, I was able to hit the brakes. I never have been able to figure what happened that day. I'm not blaming it on this thing, but it might explain it.

Also, I was getting a tire plugged and the tech was asking me to roll forward up a slight incline. I couldnt do it. the car lept 2 feet anytime I got in enough throttle to move the car. it was really wierd."

Dave Z

joenissan

LMAO...Sounds like someone who doesn't quite know how to drive a 5 speed. I hardly think the minor "fuel-cut" condition can be blamed for a car jumping 5 feet..lol...I think we're reaching now.

Joe

bigk200

I landed a little hard on you with my post yesterday. Please accept my apology. Regards.

bigk200

The throttle can be hard to control on the 2K Maxima because the engine rev's so quick when you step on the gas. Its either all or nothing.

So I am not surprised by reports that the car seems to really take off (leaping forward so-to-speak). It's completely believeable for me anyway.

y2kse

My Maxima has the most sensitive throttle I've ever experienced. I've learned to control it by being equally sensitive with the clutch engagement and inching forward in first gear from a dead stop until the clutch is fully engaged.

Inch forward or leap forward . . . those are my only choices.

Bruce . . .

jeffmaxse2k

I read that post and actually remember when he originally posted it a few months back....

He drives a GLE auto, not a 5spd. I just wanted that to be clear to the other folks here. And I'm not disagreeing with you or him...I agree that the throttle is very sensitive....I feel run up on people bumpers REAL quick with realizing it sometimes


You took quite an unwarranted bashing over there by quite a few folks which was pretty uncalled for....you think that you just insulted someone in their family!

I'm on your side and all of you with the 5spd problems...and I've got quite a few on my side in automatic world

Hey I like the car but I don't have such a blind loyalty to Nissan that I can't see its faults

kostya

Hello guys!

Ok, I registered the name
http://www.NissanMaximaProblems.com/

I still have to work out with ISP the way to
upload the useful information other there; right
now it's "under construction".

Until then--what do you think is appropriate over
there? Right now I am thinking about brief
description of the problem and links to both
"Nissan Maxima 5 spd Problems" forums.

What do you think?

davejohn

I was an owner of a grey 2000 maxima se five speed until I totaled the car on 9/29/00. A young kid pulled out in front of me and we hit pretty much head on - I was going about 40mph. Luckily, neither of us were hurt - I can attest to the safety of the Maxima. But I did not get a new Maxima because of the fuel cut/jerk problems. The maxima was beautiful, handled and accelerated well and you could say I was a loyal maxima buyer (my previous car was a 96 se five speed). So to make a long story short, I kind of gave up the fight, and because of the unfortunate circumstances was in the position to get a new car. Unfortunately, it was not a maxima. Good luck in the five speed solution. By the way, I purchased a 2001 Acura CL Type S as a replacement. So far so good!

kostya

Hello Dave

Do you mind if I quote your post #227 at
NissanMaximaProblems.com web cite?

Thanks.

joenissan

Not a problem. And I just found the pedestrian story a bit of a reach, thats all. I didn't intend for my post to be in any way insulting, so my apologies to anyone who took it that way.

Joe

bigk200

I think your ideas are good for the web site. Even if it doesn't draw a lot of hits, it will be a tremendeous "symbolic" move on the part of loyal and concerned Maxima 5-speed enthusiasts. Perhaps Nissan will someday take notice. (Or maybe I'm just dream'in!)

Send me an e:mail and let me know where to send my contribution and in what amount.

swallow@sky.net

gladichecked

If ya'll hit it a lot early, when people do a search for Nissan, it may show up and grab some attention. It's amazing what comes up when you do a search. More than once I was searching for one thing and found something else that looked interesting. 2 hours later I forgot what I was searching for in the first place...lol.

kostya

Hello Guys,

check it out--the 1st revision of
http://www.NissanMaximaProblems.com/
is up and running

So send me comments if you'd like to (link is provided on the page).

Kostya.

P.S. so far they charged me $61 for 1 yr. "parking" and $35 for registration. Anybody wants to chip-in?