G37x chugging along

[dindenver]

This has happened twice. The first time I was driving on a mountain road at 20-30 mph. Tonight it happened on the freeway merging going 50 mph. Both times there was an uphill and acceleration load on the car. It feels as if the transmission is slipping. I step on the accelerator and nothing happens. The RPMs jump but there is no acceleration. The engine sounds smooth so I don't think it is a fuel issue. Transmission?? AWD components?? I'm trying to merge and I feel like I'm losing altitude. The car shook, sputtered and chugged and I was barely able to get to the shoulder. There was a smell like something was burning. The "slip" light came on the dash. Shut it down, restarted and everything was fine. Took it to the dealer after the first incident and they said the computer had nothing unusual. They told me to downshift using the manual shifter. I tried that tonight with no luck. I'm hoping someone can give me some advice so the dealer doesn't just send me away with a pat on the head again. I easily could have caused a major accident today. If they can't help me and this happens again this vehicle is going to be history.

The car is 6 months old and has 11,000 miles on it. The car has been serviced at the dealer. Engine was warm and I am using premium fuel as recommended.

Thanks

[tollboothwilley]

Sounds to me like the transmission is in a very high gear for the RPM.

Talk to the dealership over the phone and see if there is a fix for this. I know there have been a few ECU reflash upgrades for some things like this.

You could try resetting the ECU and drive the car harder. It will stay in a lower gear longer and keep the revs higher. Adaptive learning ECU.

[dindenver]

Thanks for your reply. I'm going to the dealer tomorrow with your solution. I'm so thinking they won't do anything because it's an intermittent problem. But we'll see!

[dindenver]

The dealer didn't find anything in the vehicle's computer that documented the incident. They did find 2 service bulletins that they believe will solve the problem. They reprogrammed the ECM and TCM and hopefully this will work. Time will tell. The service manager said they've had other cars with similar complaints and this reprogramming did the trick for them.

[psmwrx]

its the 7 spd trans

[dindenver]

What do you mean "it's the 7 speed trans"?

[psmwrx]

your feel the torque converter lock up giving you that chugging/hesitant feeling

[Sentientbydesign]

Maybe you need better tires.

Are you familiar with how the VDC intervenes when traction is lost? Is this the same type of feeling?

If your SLIP light came on and stayed on, it meant your tires lost traction OR it's possible that a speed sensor is malfunctioning.

Sounds to me like the transmission is in a very high gear for the RPM.

Talk to the dealership over the phone and see if there is a fix for this. I know there have been a few ECU reflash upgrades for some things like this.

You could try resetting the ECU and drive the car harder. It will stay in a lower gear longer and keep the revs higher. Adaptive learning ECU.

SLIP light wouldn't be on if it was a matter of improper gear selection.

[dindenver]

Thanks for responding. The tires are stock Goodyear Eagle RSA with 11,000 miles on them. I've been on that road 100 times and it was clean without a problem.

I don't have a clue what the VDC does. I've never hit the VDC button. Dealer said to ignore it.

I only saw the slip light once. It didn't stay on. My focus was mostly on the traffic.

I was in normal Drive and only used the DS thinking it would help.

I'll keep the speed sensor idea in mind if the ECM and TCM upgrades the dealer did doesn't work. Hopefully it will and this won't happen again.

[Sentientbydesign]

Ok. Now that clears things up a little more.

The VDC (Vehicle Dynamics Control) is essentially traction control on steroids. If the system senses that one or more wheels are slipping, it will apply the brakes and reduce throttle input to slow down those wheels until the vehicle is going "where it's supposed to".

Turning VDC off is only recommended if you were racing or perhaps stuck in the mud/snow.

I have a strong feeling that you have 1 of 2 problems:

There is a malfunctioning sensor on the car causing the VDC to kick in (ergo the SLIP light).

You don't know how to drive the car. Sorry that that sounds so horrible, but this is a very high powered, torquey vehicle. Even with AWD, it's possible to overcome traction in a place like Evergreen where it freezes.

If the latter is the problem, I'd take the car out where you're on your own and play with throttle input to learn how much gas you can give it before it starts slipping.

[dindenver]

I really appreciate your thoughtful replies. And telling me I don't know how to drive. Tsk, tsk. But I do understand what you are saying. It is a high powered vehicle that can do things I'll probably never ask it to do. Much of this car is wasted on me! But I was in a situation I've been in 100's of times. And the first time I was going slow, again in a place I've been before. So for this moment I feel confident that I can take me out of the equation.

I do need to find an empty lot in snow to see what it does. When I test drove an Audi A4 the snow traction was incredible and I'm hoping my Infiniti will be the Audi's equal. From what I can tell it'll do the same or better.

Thanks

[Sentientbydesign]

Sorry, but I'm still trying to learn how to sugar coat things.

When I first got my G, I can honestly say I had NO experience with a car as powerful or RWD before. The combination got me in a couple of sticky situations including me being 60 degrees to the road with VDC completely braking and killing throttle on an on-ramp.

It took a while to learn how and when to use the power.

Also, hasn't your weather just gotten worse recently? Most tires are far more forgiving in warmer weather than colder. Forecast for your area shows you're just above freezing for the high and diping into the 20s for the low. Is it possible that you've been in that situation 100s of times before, but not with the current weather/temperature conditions?

[cjs37xs]

I have to say I'm with sentient...not that you can't drive, but that there must be a faulty sensor. We are essentially neighbors (I am in Colo. Springs), and I haven't had any issues with mine. I have TRIED to make it do things, in all types of situations (rain, snow, accel, decel, etc.), and I haven't had any problems with mine. I have had mine for approx. 6 months too, and right at 10K. I have not had it do anything like what you described in your OP, which is why I would think it's a sensor,and not the driver. It is a smart enough car that it will cover for a dumba$$ driver in most situations. I would think that they would be able to find something. Sorry I couldn't be of any help....

Also, did you get it at Mike Ward Infiniti, or the one in Aurora? I have had mixed feelings about the service dept. at Ward, but I will keep going there until the warranty period is complete...that's where I got mine (cuz the Infiniti dealer here in C. Springs sucks!)

[dindenver]

I'm going to Mike Ward. Since this was the 2nd event and it was clearly in a dangerous place I whined enough and the service writer had the service manager waiting for me when I arrived. I appreciated that they didn't blow me off. We'll see if the computer upgrades work. If not it's nice to have some ideas in my back pocket.

Have you had yours out in the snow? I haven't as of yet.

Drive safely and thanks.

[dindenver]

Silly person. I don't need sugar coating. The weather here gets yucky but that day it was 50 degrees and gorgeous blue skies. And the weather had been the same for a week before. Drove it today in similar conditions with no problem.

Time will tell.