Pinking after half mile

[planenut]

Can anybody suggest a possible cause for this?
Each and every time I use my Mondeo 2litre petrol, starts fine, then after a half mile, it begins to pink for the next quarter mile, then settles down again and performs fine. If I then stopped, say for a paper or for any reason, same again.

 

[keyplayer]

Lazy thermostat?

 

[planenut]

Well I know I don't know too much about the car, but why would the thermostat affect the running?
I do appreciate the fact that you have commented though.

 

[AdamW]

it begins to pink for the next quarter mile,

What, like it turns into a Mazda MX-5 or something? Does this occur more frequently when you "go west"?

The higher octane number of super unleaded might help prevent this at least until you figure out what is wrong. Not very helpful I am afraid... Have you checked your plugs?

 

[planenut]

Thank you again for the comments. No, I haven't checked the plugs, tomorrow is my day off, but (check DIY disasters) I have some more pressing things to tend to.

 

[keyplayer]

Pre ignition, ie pinking is caused by incorrect ignition timing or overheating. If your timing is wrong, I would expect it to pre ignite more permanently than you desccribe. If your thermo is taking a bit too long to open, but opening eventually, this could cause what you describe. Just a guess of course, but poss. worth a look. Besta luck.

 

[planenut]

Thank you again for the comments, a bit clearer now, but still on the back burner.

 

[david and julie]

I agree with Adam and would try a different garage for a few fill ups and see how it goes.

Sometimes air leaks on the exhaust manifold sound just like pinking when cold then go away as the engine warms up.

 

[planenut]

The effect is definitely from the missing thrust of the engine, so that's where I will start my search, when able, thank you.

 

[Bamba]

Pinking is a sharp mettalic ping under acceleration is this what you mean? Or are you talking about missfireing and loss of performance. The Zetec Ford has a problem with plug flash over on number 3 4 cyls due to the positive polarity of these two cylinders. Fit new plugs and don't gap them over 40 thou (1mm) and cleand the plug covers with WD40 an a cloth internaly.