Strange one for you!!

[vwagain]

Recently my golf had started pinking from 1750rpm to 2000rpm. I say "had" because it has out of the blue stopped altogether!!!!(pinking that is!!)  And the car feels much livelier then it ever has pulling like a train from 1500rpm onwards!!!  How and why has this happened?? Was it a bad sensor that has suddenly started working again?? The mind boggles!! 

The only thing i have done recently is to clear out and seal up a crack in the crank case breather pipe. I have a new one on order.  Surly this pipe cant have such an effect on the running of the engine can it?  It does have quite a nasty crack in the bottom bend and i was getting fumes in the car until i wrapped it with PTFE and black tape just as a standby. 

Stu

[vwagain]

Never mind, i got the answer.  "Ohh yes it can, the hose lets in unmetered air so the engines runs lean and therefore it pinks."   

Sorted
 

[Len]

I have said many times to check all the breather hoses!

[golfpro]

sorry for being think but what the hell is pinking?

[Len]

When its not firing correctly, like the timing is a bit out.
But on ECU type cars thats usually impossible, but it manifests itself as a slight hesitation, or a jump/judder.

In old cars with points it usually meant they needed changing. Or the timing was out.

Back when the change from 4 star to unleaded was around they said an unaltered car would pink on unleaded. They didnt - all it affected was the valve seats!

[vwagain]

Knocking (also called pinking or pinging)—technically detonation—in internal combustion engines occurs when fuel/air mixture in the cylinder has been ignited by the spark plug and the smooth burning is interrupted by the unburned mixture in the combustion chamber exploding before the flame front can reach it. Combusting stops suddenly, because of the explosion, before the optimum moment of the four-stroke cycle. The resulting shockwave reverberates in the combustion chamber and pressures increase catastrophically, creating a characteristic metallic "pinging" sound.

Stu