Engine & Performance
Timing Chain & Tensioner
A stretched timing chain announces itself quietly — a rattle on cold start, a correlation code, a slightly rough idle. Ignore it and the repair becomes a rebuild.
Signs you need this
- Rattle or chatter for a second or two on cold start
- Camshaft position correlation faults stored in the ECU
- Rough idle, reduced power, or a check engine light
- Chain noise that rises and falls with engine speed
How we approach it
On M271 four-cylinders the chain and tensioner are a well-known service item; on M272 and M273 V6 and V8 engines a stretched chain often accompanies the balance shaft or idler gear wear those engines are known for. We measure actual camshaft-to-crankshaft correlation with Xentry rather than judging by ear, then replace the chain, guides, tensioner and sprockets as a set. Doing the chain alone against worn guides simply buys you a repeat visit.
What the job includes
- 01Camshaft correlation measurement through Xentry live data
- 02Timing chain, guide rail and tensioner replacement as a set
- 03Sprocket and camshaft adjuster inspection
- 04Front cover reseal where the job exposes it
- 05Oil and filter service on reassembly
- 06Post-repair correlation verification and road test
Common questions
How do I know if my chain is stretched or it is just noisy lifters?
Measured correlation values settle it. Xentry reports actual camshaft deviation in degrees; anything beyond factory specification is a stretched chain and no amount of oil additive will change it.
Can I keep driving with a chain rattle?
We would not. A chain that jumps a tooth on a modern interference engine bends valves, and that turns a chain job into a cylinder head or full rebuild.
Let us take a look at it.
Call and describe what the car is doing. We will give you an honest assessment before any work begins.
7492 Slater Ave, Huntington Beach, CA 92647 · Mon–Fri 8:00am–5:00pm
Related services
Engine Rebuild
Complete rebuilds to factory tolerances for M272, M273, M156, M271, M274 and more.
Balance Shaft & Idler Gear
The M272 and M273 gear wear issue — diagnosed by serial number, quoted honestly, fixed once.
Camshaft Adjusters & Solenoids
Rattle on start-up and variable valve timing faults from worn adjusters and clogged magnets.