Loses power when driving hard on road trips - 2010 Sentra SR

Car: 2010 Sentra 2.0 SR
Issue: the car loses power when driving hard or towing. The car will not accelerate and over time just slows down. The issue is resolved if I pull over, turn the car off and wait for ~5 minutes. Never happens on short trips or city driving. If I don’t take a road trip, it can go months without happening.
No CEL or codes. Engine isn’t overheating (per temp gauge).

Please advise. Thanks in advance!

Manual transmission? Or CVT? How many miles on the car and has the CVT ever had its fluid changed?

How much weight do you tow?

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~ 195,000 miles, CVT, has had a fluid change, yet not recently. Normally, just two ebikes on a hitch mount, so ~250 pounds with the Thule rack.

That is a head-scratcher! I am leaning to the CVT giving up when hot. They normally die long before 195K, or rather people kill them with lack of maintenance.

Maybe a fluid change would give you a clue - black, nasty fluid draining may mean the CVT was slipping as it gets hot, gets even hotter so slips more and on, and on…

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Define “driving hard.”

Please describe what “will not accelerate” means. Does the engine rev normally when you push the gas pedal or not?

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Well…

… if that means one long-ago fluid change over the course of 195k miles, I think this qualifies as a trans that may have been killed by lack of maintenance.

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Thanks for questions and ideas!
Loses power = pedal to the metal and nothing. The engine does not rev up.
Driving hard = up mountain ranges, driving ~80 mph, and car loaded for trip.
CVT fluid change is overdue, yet not more than ~50k on this change.

When it loses power, it seems like there is a “governor” that is limiting RPMs. It does not seem like the CVT is slipping (engine isn’t revving with no power to wheels).

Over that 195k interval, the trans fluid should have been changed at least 6 times.
How many times was it actually changed?

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CVT fluid has been changed four times. I will do so again ASAP. Thanks!

When the transmission fluid temperature is high, the computer will reduce engine power to prevent the transmission from overheating.

Change the fluid, check that the ATF cooler is clean and free of debris.

Thank you!

Any reason not to use Valvoline CVT Full Synthetic Fluid? it is rated for Nissan NS2.

I would only use factory CVT fluid I bought at the dealer. There have been so many problems with Nissan CVTs I would take no risks.

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If “loaded for trip” means you have a bunch of luggage/etc in the car/trunk and you’ve got those two e-bikes hanging off the back of your hitch, and you’re going up mountains at 80mph, I think I know why things might be getting hot. :wink:

Your car was not designed to do that kind of labor when new. Your weight carrying capacity on that thing is about 1,000 pounds. Subtract around 200 from that for the bikes and Thule rack (which is also double your maximum tongue load). Now you’re down to 800 pounds. Load it down with a bunch of luggage/sodas/etc and that drops further, probably to around 500 pounds. If you carry a passenger, you’re already close to your max weight rating, and that’s the max rating, not “what you can comfortably carry while speeding up mountains.”

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+1
I am actually surprised that this notoriously fragile Nissan CVT is still functioning, especially in view of its maintenance. I think that the OP should thank his favorite saint for his good fortune, and then have the trans fluid changed–by an independent trans shop, NOT a chain-run shop like the scammers at Cottman, Lee Myles, Mr. Transmission, or :astonished: AAMCO.

Maybe the fuel pump can’t keep up. It might be because of a problem with the EVAP system, and the pump is having to draw fuel against an increasing vacuum.

If you remove and replace the gas cap, does the problem go away?

American Driveline, which is the parent company of AAMCO, bought Cottman a few years ago, so perhaps Cottman should also get the “horror” emoji.

:grimacing: