Chevy Blazer: P0008 Code Diagnosis

P0008 Chevy Blazer

P0008 is a somewhat uncommon OBD2 trouble code that can occur in the Chevy Blazer. It indicates that the crankshaft and camshaft are not synchronized properly, and should be considered a breakdown risk. Driving your Blazer with P0008 can lead to engine damage and a costly repair.

While P0008 is a generic code (it has the same definition for every OBD2-equipped vehicle), repair steps will vary by model year and engine type.


P0008 Definition: Engine Position System – Performance – Bank 1

P0008 Meaning Chevy Blazer

This section breaks down the definition of P0008 for the Chevy Blazer into its three main parts. Understanding exactly what the code means can aid you in making the right diagnosis.

Engine Position System

The engine position system is responsible for testing the alignment of your Blazer’s crankshaft and camshaft(s). If the alignment is off a little, the engine won’t run well. If it’s off a lot, it won’t run at all.

The crankshaft moves the pistons up and down. The camshaft(s) need to open the intake valve(s) on the intake stroke and the exhaust valve(s) on the exhaust stroke. If the timing is off even just a little bit, it can cause the piston to damage the valves.

Performance

The Powertrain Control Module (PCM) has detected that there is an issue with the crank/cam alignment. However, it has not detected an issue with any of the sensors that it uses to monitor crankshaft/camshaft performance.

Bank 1

Bank one is the side of your Blazer’s engine with the first cylinder. P0008 will be, stored in the PCM’s memory and the check engine light is on.


P0008 Symptoms: Chevy Blazer

There usually are symptoms associated with P0008. Here are the most common ones:

  • Rough running engine
  • Increased fuel consumption
  • Hard/No start
  • Lack of power
  • Noise coming from the timing chain

P0008 Causes

Here are the most common causes of P0008 in the Chevy Blazer:

  • Stretched timing chain
  • The timing chain jumped a tooth
  • Bad timing chain tensioner
  • Bad reluctor ring (on a camshaft or on the crank)

Chevy Blazer P0008 Diagnosis

Here’s what you can do to diagnose P0008 in the Chevy Blazer. Whether or not there’s going to be a timing-related TSB is going to depend on the model year and engine type. Repair steps will vary by model year.

P0008 Diagnosis

P0008 is a very challenging code to diagnose at home. Almost all of the potential fixes involve opening the engine up. We recommend taking it into a professional shop for diagnosis (which we rarely do).

Check for TSBs

Your Chevy Blazer may have a Technical Service Bulletin on file that detail timing chain issues (particularly the 3.6). You can look them up on the NHTSA website.

Type in your VIN or make/model and look through the “manufacturer communications”

Listen for a Stretched Timing Chain

If you hear a slapping sound from inside the timing cover, that would indicate either a bad tensioner or a stretched timing chain. A loose timing chain can also cause the timing chain to jump a tooth.

Check The Reluctor Wheel

The crankshaft reluctor wheel not being aligned with top dead center is one of the most common causes of P0008.


Conclusion

If your Chevy Blazer has P0008, you should not drive it. Doing so before having it checked out can potentially cause engine damage. It is a tough code to diagnose at home and is one of the few codes we recommend going to a shop for diagnosis.