MEDIUM RISK
Common symptoms
- See page for quick checks
Cost expectations
Typical costs vary by car and region. Use this as a ballpark.
- DIY / parts: £20–£80
- Garage / labour: £80–£250
Most likely causes (ranked)
Start at the top. Rule out the common, cheap causes before expensive ones.
- Misfire
- Worn engine mounts
- Vacuum leak
- Low fuel pressure
- Injector imbalance
Quick checks (fast, low-cost)
Fast checks you can do with basic tools before buying parts.
- Scan misfire counters.
- Inspect mounts for tears.
- Check fuel trims.
- Check for vacuum leaks.
- Consider injector balance test if available.
Recommended tools
These tools make diagnosis faster and stop you buying random parts.
Related fixes
If your symptoms don’t match perfectly, check these next.
What to do next
- Fix misfires first, then mounts.