Potential Causes:
* Timing Issues: This is one of the most common causes of knocking after an engine swap. If the timing belt or chain isn't properly aligned, it can lead to incorrect valve timing, which can cause severe engine damage.
* Engine Knock Sensor: The knock sensor is responsible for detecting detonation (pre-ignition) and adjusting the timing accordingly. If it's faulty or improperly installed, it might not be sending the correct signals, leading to knocking.
* Low Octane Fuel: The H22A is known for its high compression ratio. Using low-octane fuel can cause pre-ignition and knocking.
* Intake or Exhaust Leaks: Leaks in the intake or exhaust manifolds can disrupt airflow and create a knocking sound.
* Rod Bearing Failure: A knocking sound could also indicate a more serious issue like a rod bearing failure. This is more likely to occur if the engine wasn't properly broken in or if the bearings were damaged during installation.
* Piston Slap: If the pistons are loose or damaged, they can slap against the cylinder walls, producing a knocking sound.
* Valve Train Issues: Worn or damaged valve lifters, rocker arms, or camshaft lobes can cause knocking.
* Improper Engine Mounting: If the engine isn't properly mounted, it can vibrate and cause knocking.
Next Steps:
1. Check for Timing Issues:
* Double-check your timing belt or chain alignment. If you're unsure, consult a mechanic or your engine swap guide.
* You can try to reset the timing by re-adjusting it based on the timing marks on your engine.
2. Inspect the Knock Sensor:
* Check the knock sensor for signs of damage or corrosion.
* Make sure it's properly connected and grounded.
3. Use High-Octane Fuel:
* Use at least 91 octane or higher for optimal performance and to prevent knocking.
4. Inspect for Leaks:
* Visually inspect the intake and exhaust manifolds for leaks.
* Use a leak detector spray to check for leaks.
5. Listen to the Knock:
* The location of the knocking sound can help determine the cause. For example, if it's coming from the top of the engine, it could be a timing issue.
* If the knock gets worse when the engine is under load, it could be a rod bearing or piston slap issue.
6. Professional Help:
* If you're not comfortable troubleshooting engine problems yourself, consult a mechanic. They can diagnose the problem and recommend the best course of action.
Important Note: Ignoring engine knocking can lead to serious damage. If the sound is persistent or gets worse, it's essential to stop driving and address the issue immediately.
