Hi Scotty!
I have a 2015 Nissan Altima 3.5l with 100k miles. The car will drive for 20 minutes and suddenly the car will stop accelerating. I pull the car to the side of the road and sit for about 10 minutes. While the car is in park I press the gas pedal to the floor and there is no change in RPM. There is no engine stutter or stall. The center radio/gps screen and air conditioning fans power off as well. I am not seeing any CEL or dash notifications. As all of this is happening the car remains at idle. After 10 minutes of sitting on the side of the road the center radio/gps screens and air conditioning turn on and I can drive the car away. I am not seeing any overheating and all of the fluids are at their correct levels.
I changed the throttle body, mass air flow sensor, fuel pump, and brake sensor relay for the car. The voltage of the battery and the alternator on/off are all within normal range. We brought the car to several shops and it is not showing any codes.
Thank you!
I changed the throttle body, mass air flow sensor, fuel pump, and brake sensor relay for the car.
Did those test as bad before you replaced them? Did you use OEM parts?
We brought the car to several shops and it is not showing any codes.
What about live data, maybe capturing the data stream when the problem occurs so it can be analyzed? Checking for codes is just the bare beginning of the diagnostic process.
The shop had their scanner hooked up to the car and drove it. The issue happened while the mechanic was driving it and no codes showed up. They say it might be the CPU but that seems like a blanket response. It's just strange the radio and electronics shut off when this happens but return to normal when the car can drive again.
The mechanic suspected the pump, maf, and throttle body were the issue but it was not. I replaced the brake relay switch with an OEM switch. The brake switch was weird but it had to do with cutting off the fuel as per YouTube mechanics. Unfortunately that did not work.
@chasefulton If all they did was look for codes they didn't do a proper job of diagnosis. The data stream needs to be analyzed for problems.
Unfortunately this is where I'm at. Numerous shops I've been to can't find the problem. It's to a point now where I'm getting turned away because they say the work done was what they would have done. It seems like time is money and mechanics can't be bothered with this problem.
The same thing happened again today. Still the engine remains at idle but won't rev past idle. This time the "PS" and "Traction" light came on. Still there was no CEL. After sitting for 10 minutes at idle the lights went off, radio powered on, and I was able to drive away. Is this the CVT overheating?
@chasefulton Doesn't the car have a CVT overheating light? Of course on one of those cars it would be no surprise for the CVT to fail but you'd have the opposite symptom, the engine would rev up without corresponding motion from the car.
The answer to this problem will likely be found in the data. Take a look at at youtube mechanic channels like South Main Auto and Pine Hollow Auto Diagnostics. They don't just throw their hands up and say "no codes, nothing we can do" - they dig deep into the data stream to analyze problems.