P0008 is a somewhat uncommon OBD2 trouble code that can occur in the Cadillac STS. It indicates that the crankshaft and camshaft are not synchronized properly, and should be considered a breakdown risk. Driving your STS 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
This section breaks down the definition of P0008 for the Cadillac STS 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 STS’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.
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 one is the side of your STS’s engine with the first cylinder. P0008 will be, stored in the PCM’s memory and the check engine light is on.
P0008 Symptoms: Cadillac STS
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
Here are the most common causes of P0008 in the Cadillac STS:
- Stretched timing chain
- The timing chain jumped a tooth
- Bad timing chain tensioner
- Bad reluctor ring (on a camshaft or on the crank)
Cadillac STS P0008 Diagnosis
Here’s what you can do to diagnose P0008 in the Cadillac STS. 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 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 Cadillac STS 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.
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.
If your Cadillac STS 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.