revmatch skipping and stuck in sport
 

hi guys
i was driving home tonight in my 2014 sport model. All of a sudden when accelerating around 3000rpm the car would revmatch even though it wasnt needed and would jerk the car... this happened in 1-3 gears. I ended up making it home but tried to turn off sport mode hoping that would help and nothing happens when i press the sport button.
Anyone have ideas what the problem is and how i can fix it!?

w0wieet,

Assuming you mean "S Mode" when you wrote "sport mode", are you aware that the switch must be held down for more than one second in order to turn the rev matching system off?

You press the button down to turn the S mode on, but you must hold the switch down for more than one second to turn it off.

The S mode system involves a multitude of system inputs from the crankshaft position sensor, the cam shaft position sensor, the clutch position switch, the clutch interlock switch, the gear lever position sensor, the engine input sensor (speed), and the combination meter (speedometer/tach) all into the ECM, and then depending on the S mode switch setting, the magic takes place. (I just copied all of this from the factory service manual, certainly not because I'm a knowledgeable tech.)

From all of that you can understand why it'll be unlikely that the average owner will be able to correct the issue. That said, the S Mode system diagnosis starts on page EC - 126 (Engine Control section, page 126) and goes beyond page 531 in the 2016 service manual.

I think you'll find that a service tech using the Nissan Consult computer may be able to narrow down your issue quickly to the fault, saving you a lot of frustration, and yes, it'll cost some bucks.

Or maybe someone here has had your same problem before, and will jump in? Good Luck!

Have you tried unhooking the battery for a few min and then starting up the car for the ecu to relearn?

I remember when i had my car tuned we had to reset the smode position sensor

Not sure what your describing is what I am picturing. When your in 2nd gear accelerating and going to 3rd the car is rev matching to 1st causing the car to jerk forward? If so there is something definitely wrong with the system and you should try and reset it our your going to have to bring it in for service, it doesn't sound like a problem the average DIYer can solve.

PS It's SynchroRev Match mode or S-Mode for short, there is no sport mode.

As per others, the first thing to try is resetting the ECM. You can pull a battery cable and press on the brake pedal or there is a procedure that doesn't require disconnecting the battery. If that doesn't fix the problem, I'd next look at the shifter position switch assembly (don't remember what the official name is - it sits at base of shifter).

The FSM (link in sig) has some great troubleshooting info.

update. dealership says i need a new engine and that it was cometly out of oil.
at no time did an oil light ever come on. i didnt save the service history so i think im ******. anyone know the cost of a new engine? any other thoughts?

Yeah, it's called GO TO ANOTHER DEALERSHIP! Or better yet, go to a well known and knowledgeable mechanic. Highly doubt it's an oil issue or that you need a new engine.


And on that note, another reason why I chose the base model Z. None of that that techno-crap to go wrong.

When was the last time you checked or changed the oil? Any oil spots under the car?

One of the most common issue for the car revving up is driver error. If you hit the gate of a lower gear by mistake, it will rev up thinking you are downshifting. It happens to me sometimes if I get sloppy shifting.

Yeah I have a bad habit of fidgeting with the shifter when I am coasting to a stop in neutral... SRM would sometimes be like ".......WAAAAAHHHHHHHH" and people around me in traffic be so confused.

First, go to another mechanic. A reputable one not employed by Nissan.

If in fact the engine is shot, you can get a used one online for about $2,500, but that doesn't include the labor to install it. A brand new one from Nissan will be a lot more.

I highly doubt a Nissan dealer would just tell him that for the hell of it...

Though I too am most curious about your habits regarding oil changes, checking your oil level etc..

Does the car even have an indicator for low engine oil level?

It has a warning light, but if it comes on, chances are the engine is already done.

Wow...that's kinda scary...I get my oil changed every 4k miles like clockwork but I rarely if ever check the level...suppose I need to now for sure.

You should check all fluid levels (that you can; can't check trans or diff level easily) and tire pressure at least once per month. Once a week isn't too often. Check condition of belts and tires while you're at it.

If you want to go the distance, install an oil pressure gauge.

I have a habit of checking my Oil and My SC oil at EVERY fill up. simple and might just save your bank account.

My routine too. If im off a spirited run pull up let car run a bit with hood up to get oil temps down.

Gas up
Check oil
Check brake and clutch lvls and any substantial color change

Reset odo A (b is reset every oil change)

Wave to the gas clerk (they know and watch me everytime)

Slowly ease out of gas station and then redline first.

OP's profile indicated he/she drives an 2005 350z. :confused:

To a certain extent, I disagree. If you have the car in the air for an oil change, it is not difficult to open the fill plug and stick a finger in to verify the level of the fluid is even with the fill opening. This is applicable to the diff and manual transmissions. Automatics are slightly more difficult since the fluid level needs to be checked with the fluid heated to a certain temp and not cold. You will need a new washer for the fill plug each time is about the only downside (~$1).

True if doing an oil change but not so much if just doing a periodic fluids check.

True if one has some mechanical experience and the right tools. Sounds like OP may not have either one.

But, yeah. If one can check trans/diff, one should do so every now and then.

I'm getting too old to be crawling under cars. :)

i had synthetic oil change 6000 miles ago and have been told synthetic should be done every 5k...so just slighlty over... either way i do not think an engine with no signs of oil leaks should be completly bone dry unless its Nissan fault especially with no indications anything was wrong or an oil light.
i found both my oil receipts from service this year.

These engines are hell on oil. I change every 4k. I use synthetic also.

Why do you say that? I do the same but every oil analysis I get back even with 4k and a full track weekend the results still say the oil is good for longer.

Yeah I change at 4k (synthetic) as well but I know damn well I could probably go for double that and be fine. People thinking they need to change their engine oil every 3k miles (even non synthetic) is the one of the biggest scams in automotive history IMO. :stirthepot:

:iagree: :iagree:

Furthermore, I also don't find the engine have any oil consumption issue as other stated. Again this is only based on my experience with the Z and G37s.

Dealers aren't suggesting 3000 mile OCIs any longer. Most owner's manuals suggest 7500 miles or more these days for new cars. Some new Fords are on 12K mile intervals.

The real scam is $80+ for an oil charge when I can find Mobil 1 for $25 at Walmart and most shops charge $10-15 for labor.

If you want a real idea of what your OCI should be for your specific car, get an oil analysis done by Blackstone Labs.

Full Synthetic oil can handle 7500 miles without any issues. I was told by some that even conventional oil can go 5000 miles easily.

BMW M3 has an 15k miles oci.

My concern about oil change interval is not about miles, its about time. I can never reach the miles in a single year that would require me to change the oil in my Z. I change the oil at the end of each driving season / year before putting the car in storage. On the topic of oil use, I have not had any oil use issues with either of the Z's I currently own or have owned in the past. Like it's been said, I am going on personal experience.

The way those M3's spit out crank and rod bearings I wouldn't use that car as an example. Just sayin.