Chevrolet Tahoe Ignition and Engine Management: 4 Symptoms Worth Taking Seriously (2015-2020)

Most ignition and engine management problems announce themselves well before they strand anybody. On a 2015-2020 Tahoe, these are the ones worth acting on.

1. A rough idle that smooths out above 2,000 rpm

By the time this is obvious you are generally replacing more than one part. Start by looking at spark plugs.

2. A misfire code that follows the coil when you swap it to another cylinder

By the time this is obvious you are generally replacing more than one part. Start by looking at crankshaft position sensors.

3. A check engine light that flashes under load, which means raw fuel is going into the converter

It rarely gets better on its own, and it usually gets louder before it gets expensive. Start by looking at ignition coils.

4. Fuel economy that drifts down a mile or two per gallon over a few months

It rarely gets better on its own, and it usually gets louder before it gets expensive. Start by looking at spark plugs.

What to Do Next

Iridium plugs on most modern GM engines are a 90,000 to 100,000 mile item. Coils are replaced on failure, not on a schedule.

The same nameplate can have three different engines in one model year. VIN is the only reliable way to get the right plug.

Everything here is available as a genuine GM part through our Chevrolet OEM parts catalog. If you would rather search directly, search for Tahoe spark plugs.