Engine Compression Test Cost Breakdown
Basic Compression Test
Labor Time: 1-1.5 hours
Cost Range: $125-$187.50
Includes testing all cylinders and providing a basic diagnostic report.
Wet Compression Test
Labor Time: 1.5-2 hours
Cost Range: $187.50-$250
Includes basic compression test plus additional testing with oil added to cylinders to diagnose ring issues.
Cylinder Leakdown Test
Labor Time: 2-2.5 hours
Cost Range: $250-$312.50
Most comprehensive test that includes pressurized testing to identify specific areas of compression loss.
Additional Diagnostic Services
If further diagnosis is needed after compression testing:
• Valve adjustment check: +1 hour ($125)
• Head gasket inspection: +1.5 hours ($187.50)
• Timing component inspection: +2 hours ($250)
Note: These prices reflect labor costs only. Additional parts or repairs identified during testing will be quoted separately. Some vehicles may require additional labor time due to accessibility or complexity.
Why Choose Professional Compression Testing
Professional compression testing helps identify engine problems early, potentially saving thousands in repairs. Our certified technicians use professional-grade equipment and provide detailed reports to help you make informed decisions about your vehicle's maintenance.
Engine Compression Test Repair Procedures
Dry Compression Test
Purpose:Measures the ability of your engine's cylinders to compress air without any additional substances.
Repair Steps:
- Warm up engine to operating temperature
- Remove all spark plugs
- Disable fuel and ignition systems
- Insert compression gauge into spark plug hole
- Crank engine through several revolutions
- Record readings for each cylinder
- Compare readings to manufacturer specifications
- Reinstall spark plugs and reconnect systems
Wet Compression Test
Purpose:Determines if low compression is caused by worn rings or valve issues by adding oil to the cylinder.
Repair Steps:
- Perform dry compression test first
- Add 2-3 teaspoons of engine oil into cylinder
- Insert compression gauge
- Crank engine several times
- Record new readings
- Compare to dry test results
- Clean excess oil
- Reinstall components
Running Compression Test
Purpose:Measures compression while engine is running to detect issues not apparent in static tests.
Repair Steps:
- Connect specialized running compression tester
- Start and run engine at specified RPM
- Record readings for each cylinder
- Compare cylinder-to-cylinder readings
- Analyze waveform patterns
- Remove testing equipment
- Return engine to normal operating condition
Cylinder Leakage Test
Purpose:Identifies where compression is being lost in the cylinder.
Repair Steps:
- Warm up engine to operating temperature
- Remove spark plugs
- Set piston to TDC on compression stroke
- Connect leak-down tester to cylinder
- Apply compressed air
- Listen for air leaks at:
- Intake valve
- Exhaust valve
- Crankcase
- Radiator
- Record percentage of leakage
- Repeat for all cylinders
- Reassemble all components
Note:These tests should be performed by qualified mechanics using proper equipment and safety procedures. Results help determine if repairs such as valve jobs, ring replacement, or complete engine overhaul are necessary.
Contact our certified technicians today to schedule a comprehensive engine compression test for your vehicle.
Understanding Engine Compression Tests
Dry Compression Test
ADry Compression Testis the initial measurement of compression in each cylinder without any additional substances. During this test, the technician:
- Removes all spark plugs
- Disables the fuel and ignition systems
- Inserts a compression gauge into each cylinder
- Cranks the engine to measure pressure
This test provides baseline readings for each cylinder's compression and helps identify potential issues like worn piston rings, damaged valves, or blown head gaskets.
Wet Compression Test
AWet Compression Testfollows the dry test and involves adding a small amount of engine oil to each cylinder before testing. This test:
- Temporarily seals worn piston rings
- Helps diagnose whether low compression is due to ring or valve issues
- Provides comparative readings to the dry test
If compression readings significantly improve after adding oil, it typically indicates worn piston rings. If readings remain low, the problem likely lies with the valves or head gasket.
Running Compression Test
ARunning Compression Testmeasures cylinder compression while the engine is operating. This test:
- Evaluates compression under actual running conditions
- Helps identify problems that may not show up in static tests
- Measures dynamic compression during engine operation
This test is particularly useful for detecting issues that only manifest when the engine is running, such as timing problems or valve train issues.
Cylinder Leakage Test
ACylinder Leakage Test, also known as a leak-down test, measures how well each cylinder holds pressure. During this test:
- Compressed air is introduced into each cylinder
- The percentage of air leakage is measured
- The location of leaks can be identified by listening for escaping air
This test is extremely valuable for pinpointing the exact location of compression losses, whether through valves, piston rings, or head gaskets.
Note: Regular compression testing is essential for maintaining engine health and preventing major repairs. If you notice decreased engine performance, rough idling, or starting problems, scheduling a compression test is recommended.
Common Signs of Engine Compression Problems: Understanding Test Failure Symptoms
Engine Compression Test Types and Indicators
Dry Compression Test
Signs of Failure:
- Readings below 100 PSI indicate significant wear
- More than 10% variation between cylinders suggests problems
- Low compression in adjacent cylinders often indicates head gasket failure
- Consistently low readings across all cylinders suggests worn piston rings
Service Schedule:
Recommended every 50,000 miles or when experiencing power loss, rough idle, or starting difficulties.
Wet Compression Test
Signs of Failure:
- If readings significantly improve after adding oil, piston rings are likely worn
- No improvement after adding oil suggests valve or head gasket issues
- Readings still below 100 PSI indicate serious engine wear
Service Schedule:
Performed immediately after a dry compression test shows low readings to diagnose the specific problem area.
Running Compression Test
Signs of Failure:
- Fluctuating readings indicate valve timing issues
- Consistently low readings suggest worn valve guides or seals
- Erratic readings between cylinders indicate valve train problems
Service Schedule:
Typically performed when diagnosing specific valve-related concerns or during major engine service intervals.
Cylinder Leakage Test
Signs of Failure:
- Air escaping through intake indicates intake valve issues
- Noise from exhaust suggests exhaust valve problems
- Bubbles in radiator point to head gasket failure
- Air noise from crankcase indicates worn piston rings
Service Schedule:
Recommended annually for high-performance engines or when compression tests indicate potential issues.
Note: These tests should always be performed by qualified technicians using proper equipment and following manufacturer specifications.
How It Works
- Get a quote online or set-up a time to have your vehicle looked at.
- Pick time slots that work for you, easily, online.
- We will confirm appointments and send reminders.
- Our mechanics bring everything that is needed to you.
- All you have to do is provided a safe area for the work to be performed.
What we need from you
- A safe place to work on your vehicle
- No working on the side of busy roads
- No working on unstable or steep surfaces.
- We do not perform repairs during severe weather.
- Authorization from a property owner or management.
- Repair work done in a parking lot or at your requires permission.
- We do not do repairs in areas restricted by law.
Common Questions
Service Area
Our primary service area is greater Grand Rapids and includes Comstock Park, East Grand Rapids, Grandville, Kentwood, Walker, and Wyoming
Our secondary service area is provided by our Belding location and includes: Belding, Greenville, Ionia and the sorrounding areas.
Contact us if you have any questions about where we provide services.
