RPM Bounce when not driving “fast”

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Dat1dude15

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Afternoon! New member here. I have a 2018 QX80 with roughly 90k miles on it. Recently the rpm’s started kind of bouncing down then back up around 2nd, 3rd and 4th gear, it only noticeable when I’m cruising and not gunning it. It DOES NOT fluctuate/bounce when I switch gears manually. Any ideas??
 
getting a check engine lamp? had any work dont on it recently? have you had it a while or a recent purchase?

so you mean you can be going at 50 mph and all of a sudden the rpm will increase? is the tranny slipping? meaning does it feel like you put the car in neutral then put it back in drive?

had any maintenance done on it? plugs? coil packs? maf cleaned? cats? o2 sensors? any of that been maintenanced?
 
marctronixx said:
getting a check engine lamp? had any work dont on it recently? have you had it a while or a recent purchase?

so you mean you can be going at 50 mph and all of a sudden the rpm will increase? is the tranny slipping? meaning does it feel like you put the car in neutral then put it back in drive?

had any maintenance done on it? plugs? coil packs? maf cleaned? cats? o2 sensors? any of that been maintenanced?
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No CEL or codes when scanning with OBD2.

No work done aside from new tires.
I have had it about a year.

It only bounces after changinggears, if I’m going 50 it will be steady for the most part.
Transmission is not slipping or at least noticeably. If you didn’t look at the tachometer you would even know it was happening.

I got the car at 60 k and have only done oil changes and rotations.

I can upload a vid on YouTube and post link here.

Also worth noting a slight tap on gas will make rpm’s temporarily shoot up then go back down. Like it’s overly sensitive
 
sometimes the shift points get out of whack as the car learns your driving habits. one way to clear those shift points is to reset the ecm. this procedure requires key on/off and pedal presses to clear the shift points. if done properly, you gina some low end torque and shifting could improve.

www.clubarmada.com

Resetting the ECU

Hey all, I've been reading about the timing advance and ECU resets over at clubtitan.org. Some pretty interesting stuff! SCR38 can I'm sure answer any tech questions (as he's the guru here) but I wanted to post these procedures for our site as well. Apparently what happens is that the ECU in...
www.clubarmada.com www.clubarmada.com

the steps herein apply to the infiniti as well.

this may/may not cure whatever you are seeing but you will certainly notice a difference.
______________________________
 
marctronixx said:
sometimes the shift points get out of whack as the car learns your driving habits. one way to clear those shift points is to reset the ecm. this procedure requires key on/off and pedal presses to clear the shift points. if done properly, you gina some low end torque and shifting could improve.

www.clubarmada.com

Resetting the ECU

Hey all, I've been reading about the timing advance and ECU resets over at clubtitan.org. Some pretty interesting stuff! SCR38 can I'm sure answer any tech questions (as he's the guru here) but I wanted to post these procedures for our site as well. Apparently what happens is that the ECU in...
www.clubarmada.com www.clubarmada.com

the steps herein apply to the infiniti as well.

this may/may not cure whatever you are seeing but you will certainly notice a difference.
Click to expand...
Gave it a shot, no dice. Still bouncy lol. Thank you though this could still come in handy down the line again.
 
are you sure you were able to do these procedures properly? a thing about them is you have to be precise with the timing of the pedal/key on-off. as mentioned even turning the car on after this you will see a big difference in starting it and especially the low end. not saying you did not do it but that is an obvious part.

so if its not that, and you are not pulling any error codes, and IF the car drives normally even if you see the rpms fluctuate, maybe there is some electrical issue? its really hard to understand what you are experiencing without seeing it in person.

can you reproduce this every time? does it happen no matter if its on a hill or descending or any mph?

how old is your battery? you could have a weak battery, you could have some ground strap issues.. just a number of things to eliminate...

did this just start out of the middle of nowhere? did you see it slowly start or just boom goes the dynamite it just did it one day? :)
 
Eng.q8 said:
2018 nissan armada,160k.
Having the same exact issue.
Still didn't figure out what causes the problem.
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Car is in the shop, if I have a fix I’ll let you know.

marctronixx said:
are you sure you were able to do these procedures properly? a thing about them is you have to be precise with the timing of the pedal/key on-off. as mentioned even turning the car on after this you will see a big difference in starting it and especially the low end. not saying you did not do it but that is an obvious part.

so if its not that, and you are not pulling any error codes, and IF the car drives normally even if you see the rpms fluctuate, maybe there is some electrical issue? its really hard to understand what you are experiencing without seeing it in person.

can you reproduce this every time? does it happen no matter if its on a hill or descending or any mph?

how old is your battery? you could have a weak battery, you could have some ground strap issues.. just a number of things to eliminate...

did this just start out of the middle of nowhere? did you see it slowly start or just boom goes the dynamite it just did it one day? :)
Click to expand...
It kind of just started out of the blue, now it happens on every drive when not running it hard. Battery is fresh.
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One mechanic suggested a problem with the torque converter.
 
Dat1dude15 said:
On my QX80 I just had the Torque converter replaced. The rpm’s are not as bouncy/fluctuating but the issue is still there :(
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Have you changed the transmission oil when replacing the Torque converter?
 
Eng.q8 said:
Have you changed the transmission oil when replacing the Torque converter?
Click to expand...
They drained and replaced when replacing the torque converter
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Dat1dude15 said:
They drained and replaced when replacing the torque converter
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I've read on Instagram related to Nissan Patrol Club, which people experience the same issue. They all confirmed that the problem is with the Torque converter and the easy fix for it is to add "instant shudder fixx". They claimed that the problem permanently resolved. For myself, I will try it soon.
Good luck and here is the link:

 
I have a 2014 QX80 that had 194,000 miles on it when rpm bounce began. The bounce would occur when the vehicle approached 1650 rpm's. After much reading, I changed spark plugs and coil packs first. Then, I had a transmission service performed and had anti shudder added. Still had the rpm bounce. After more research, I had someone tell me to check my electronic fan clutch. I checked the fan clutch and mine was bad. I ordered a new fan clutch from Rock Auto for $158 and installed on my vehicle. The rpm bounce was gone. That was 6 months ago and I now have 208,000 miles on the vehicle and still no rpm bounce. Many will say the electronic fan clutch could not cause rpm issues, but replacing it fixed my issue. Hope this helps someone on the forum.
 
rogthebuilder83 said:
I have a 2014 QX80 that had 194,000 miles on it when rpm bounce began. The bounce would occur when the vehicle approached 1650 rpm's. After much reading, I changed spark plugs and coil packs first. Then, I had a transmission service performed and had anti shudder added. Still had the rpm bounce. After more research, I had someone tell me to check my electronic fan clutch. I checked the fan clutch and mine was bad. I ordered a new fan clutch from Rock Auto for $158 and installed on my vehicle. The rpm bounce was gone. That was 6 months ago and I now have 208,000 miles on the vehicle and still no rpm bounce. Many will say the electronic fan clutch could not cause rpm issues, but replacing it fixed my issue. Hope this helps someone on the forum.
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How did you go about testing the clutch? I just purchased a 2016 QX80 with 90k miles, and it was the first thing I noticed on my first drive. You aren't the first one I've seen say the fan clutch, I've read several times now where that ended up being the culprit. People have replaced the transmission, valve body, torque converter, so on and so forth. It would make since that it could be the fan clutch as it does increase with rpm.
 
I talked with a mechanic that said to let the vehicle run about 10 minutes to warm up. Then, check to see how the fan is turning. Does it appear to be running slow or turning with the engine normally. My fan clutch appeared to be turning slower than it should. I ended up taking a piece of 1/2 inch pex plumbing pipe, which is extremely flexible, and tried stopping the fan from turning. I could immediately stop the fan from turning with mild pressure from the pex pipe. That is how I diagnosed my clutch fan issue. (The disclaimer is the pex pipe is not ASE certified as a diagnostic tool). There are also several videos online about how to diagnose fan clutch issues. Good luck!!
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Dat1dude15 said:
Afternoon! New member here. I have a 2018 QX80 with roughly 90k miles on it. Recently the rpm’s started kind of bouncing down then back up around 2nd, 3rd and 4th gear, it only noticeable when I’m cruising and not gunning it. It DOES NOT fluctuate/bounce when I switch gears manually. Any ideas??
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I have a 2014 QX80 with the same issue. I've tried doing the transmission fluid change and adding shudder fixx and it worked for several months. It started back up recently and I'm looking online for a permanent fix and found that there was an infiniti service bulletin about this problem. It was infiniti summary ITB14032. It is crazy that so many people have this issue and clearly Infiniti knows about it but they are no issuing a recall. The bulletin explains what the service tech should do to fix it. The subject is titled: SB 2014 QX80 lock-up torque converter disengaged under light acceleration.
 
I'm a little late to this discussion, but I am searching for a fix for this "shudder" "rpm bounce" as well on my wife's 14 QX80. It was originally diagnosed as a torque converter by a trusted mechanic but he said to try the reprogramming of the TCM by the dealer first. Another trusted source at a transmission shop recommended reprogramming the TCM as well and he did not think it was a torque converter issue. So I had the TCM flashed by the dealer, $430, and it changed the shudder and rpm bounce to a different shift point but it still does it. I would say that it is 75% better than it was, but it is not fixed. Just different. I'm now curious about this electronic fan clutch possibility. IMO mine acts too much like a slip in the transmission for it to be the fan clutch but I have old school opinions about what the fan clutch does and maybe I'm way off and wrong about it. I would love for someone to tell me exactly what it is so I can fix it without multiple expensive guesses. It seems that as common as this issue is, there should be a definite solution that fixes all. BTW, the dealer and local tranny shops will not replace a torque converter around here. they only replace tranny and TC as an attempt to fix. That's $8k. This vehicle is no longer worth $8k, especially now that box catalytic converters need to be replaced. car has 168,xxx miles.
 
Speed121 said:
I'm a little late to this discussion, but I am searching for a fix for this "shudder" "rpm bounce" as well on my wife's 14 QX80. It was originally diagnosed as a torque converter by a trusted mechanic but he said to try the reprogramming of the TCM by the dealer first. Another trusted source at a transmission shop recommended reprogramming the TCM as well and he did not think it was a torque converter issue. So I had the TCM flashed by the dealer, $430, and it changed the shudder and rpm bounce to a different shift point but it still does it. I would say that it is 75% better than it was, but it is not fixed. Just different. I'm now curious about this electronic fan clutch possibility. IMO mine acts too much like a slip in the transmission for it to be the fan clutch but I have old school opinions about what the fan clutch does and maybe I'm way off and wrong about it. I would love for someone to tell me exactly what it is so I can fix it without multiple expensive guesses. It seems that as common as this issue is, there should be a definite solution that fixes all. BTW, the dealer and local tranny shops will not replace a torque converter around here. they only replace tranny and TC as an attempt to fix. That's $8k. This vehicle is no longer worth $8k, especially now that box catalytic converters need to be replaced. car has 168,xxx miles.
Click to expand...
I did the drain and fill as described in the manual, being 3 times, and put instant shudder fixx in on the last time as I seen alot of people doing this. It fixed the issue completely. Video on YouTube, but also seen it posted around forums as well. Been 20k miles now with no bouncing.
 
Did you drain and fill the tranny 3 times yourself? How bad was that process? And was the shudder fix put in just like transmission fluid?
 
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