Question about when to use Redex

[mightykaboosh]

Hi,

I came back of holiday, after lending my car to my sister and my fiat punto 03 multijet feels sluggish. Top speed is fine its just 1st gear and second gear pick up.

I've bought some Redex from Tesco as it's on offer at the moment £2.

When can I put it in..... I'm skint and don't want to put it in on an empty tank and then refill.

Is it possible to add it to half a tank, like I've got now to top it up to full, or would that reduce its potency?

Why would there be any difference. It's still in there and it'd still mix?

Sorry, not very technically minded and would really welcome some help- thanks.

(Other thing was, when I hammered it today for about 3 mins said 110 on the speedo- and a big puff of smoke came out- almost like a sneeze.... then disappeared cars done 45k and I only really use it round town)

 

[jordanthomson]

redex should be fine on half a tank its just recommended to run on full tank to get optimal use from it,

but to me it sounds as if you could have a slighter bigger problem is there any other symtems? go out and rev the car start with little revs and then revv high 3 or 4 times but between each high rev do several low revs check for any black smoke out the back/blue also let me know of any funny sort of noises that isnt normal.