pinking,

Its when the fuel/air mix in the cylinder explodes under compression before the spark plug ignites it (which is how a diesel engine works)

This is bad as the explosion gives much higher temps and much greater shockwaves. This will lead over time to burnt/damaged pistions/valves/bores.

This can be cured by advancing the spark timing so it starts the controlled burn before the mixture pops (requires work on the ECU) or by using higher octane fuel which resists going pop much better (requires more money at the pumps). UK subarus ECU's are mapped for UK fuel and it should not be a problem, imports are a different matter.

High speed pinking is virtually undetectable by ear, but low speed pinking sounds a bit like a diesel engine (for obvious reaasons)

My mk1 astra used to do it a lot, sounds a bit like a load of marbles being shook in a can

Pinking is also called knocking or pre-ignition and their is a device called a knocklink which can detect it occuring (not got one myself)

[Edited by Gary C - 11/2/2003 5:09:23 PM]

[Edited by Gary C - 11/2/2003 5:11:20 PM]

[Edited by Gary C - 11/2/2003 5:13:02 PM]

 

never really knew what PINKIN noise was, and did'nt really bother me,...but as i bought my first scooby the other day i thought i shoud know what it souds like!.........who can tell me??

 

cheers 4 that Gary!

 

Also also called det or detonation.