However, I can only speak from experience, so here goes.
As a couple of you helpful gentlemen know, i recently acquired a Citroen Synergie HDi (the one with the brakes that kept locking on-now sorted)
Anyway, when I bought it it was smoking profusely which i originally thought was due to a broken swirl valve (alas, it wasn't). Safe to say, this was/is just a tired old engine and I was looking at the thick end of a few hundred quid to replace it.
Then I read the Ametech write up and decided to try it (what the hell, £26 including delivery wasn't much of a gamble.)
Followed the instructions religiously, applied the Ametech and have now done over 1000 miles.
I have to say that originally, you could not stand at the exhaust outlet and still be alive to tell the tale, the smoke from it (Blue/Grey) was enough to choke a ruptured donkey with gout, or even me. However,




It may well be that it is just a brief respite before something terminal happens, but, I could not have hired this car for £26 for the length of time I have driven it so far.
So I would just like to say, if you are faced with what appears to be a short lived engine, then I would certainly recommend giving Ametech a try
By the way, before anyone says it or thinks it, I am not connected to the company, I do not know anyone who works for the company and I am not getting paid to write this. I'm just a hard up motorist who tried something that worked for me but hey, it may not work for you, though I can't see why not.