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Nissan Quest engine died- p0325 Knock Sensor

On my way home late at night, my tachometer started jumping a little, and the engine was rough. Then after another minute the lights dimmed and the engine died. It wouldn’t start again. The next morning, it started right up, and it seemed fine. Drove it to the mechanic, he took it for a drive on the freeway, then after he got off the freeway it died again and had to be towed. The error code on the computer is P0326- Knock Sensor. I had the same sensor activated a couple of years ago, and my awesome mechanic (sadly, we have since moved far away, so I don’t have access to the same guy) gave the engine a tune-up and replace the spark plugs and everything was fine (well, for two years). The car has been idling rough, and the intake manifold may be warped. Could the intake manifold cause this? Distributor? Any ideas?

what year is this quest?

It’s a 2000, has around 140,000 miles on it.

My WAG is that you have something under the hood that’s reacting to heat, causing misfiring, and that misfiring is causing preignition that’s tripping your knock sensor. A bad Mass Airflow sensor, a bad Manifold Absolute Pressure sensor (your car has both), or perhaps something that directly affects your ignition timing, is providing an erroneous signal when it’s hot and causing slight preignition due to a lean fuel mix or a slightly advanced spark timing. Normally I’d expect those to trip their own codes, but things are often not perfect.

One tip you might get is in checking your spark plugs. I’ve attached a few reference charts that might help. How a plug fires can often provide a clue to how the engine is running.


Beyond that, the signals from these various sensrs can be checked to see if one is out of spec. A diagnostician with a scope can look at them