Misfire or CVT Failure? Diagnosing Hesitation on a 2016 Infiniti QX60

By: A determined owner and a NICOclub staffer with some serious diagnostic skills!

What feels like a CVT about to fail may not be a transmission issue at all. Here’s how one owner traced it to the real culprit.

Background

Vehicle: 2016 Infiniti QX60
Mileage: 125,000
CVT/Front/Rear Diff fluid changed at 75K and 105K miles
Issue: Jerking at 1,900–3,000 RPM, often confused for CVT “judder”

Initial Symptoms

Intermittent jerking during acceleration (in all gears, even in manual mode)
CEL triggered with P0302 (Cylinder 2 Misfire), later a P0300
No codes related to CVT judder (P17F0 or P17F1)

Ruling Out a Failing CVT

A failing CVT usually exhibits symptoms like:

“Judder” under light throttle, especially uphill
Visible RPM fluctuations not tied to throttle input
Stored P17Fx codes in the TCM

None of these symptoms were present. A scan using the CVTz50 app showed:

Healthy transmission pressures
Normal operating temperatures (thanks to the 140F external cooler)
No stored CVT codes

Steps Taken

Replaced Cylinder 2 coil pack — reduced misfire, but not resolved
Replaced spark plug — improved performance slightly
Reviewed fuel trims (STFT/LTFT) — no signs of injector failure or vacuum leak
Suspected carbon buildup — ran Seafoam and BG44K through intake and fuel tank
Cleaned MAF sensor using CRC MAF Cleaner
Performed IAVL procedure using CVTz50 to reset idle air values

Resolution

After cleaning the MAF and performing the IAVL, the car ran smoothly for over 1,000 miles, including a round trip from Charlotte to Columbus.

The culprit? A dirty MAF sensor and piston crown carbon buildup — not the CVT!

Takeaways for Other Nissan / Infiniti CVT Owners

Don’t jump to CVT failure. Misfires and ignition issues can mimic transmission problems.
MAF cleanliness matters. Dirty readings can throw off fuel trims and cause misfires.
Carbon buildup can cause misfires. Seafoam or ATF induction can help clean the combustion chambers. NOTE: This *must* be done properly!
Use OEM ignition parts. Aftermarket coil packs often don’t hold up.
Apps like CVTz50 provide powerful diagnostic tools for Nissan/Infiniti CVTs.