best fuel system cleaner to add to gas tank ?

A cleaner wont help, new plugs, clean the rotor and cap, a stretched timing belt, old thick oil, sticking brakes, bad thermostat can, tune it up.

I use Lucas fuel system conditioner. I dont know how it works I THINK? it cleans the injectors.

I was supremely sceptical about this additive when my son told me about it, being of a naturally sceptical nature and 73 years old and having heard it all ?

He bought an old camper van which he renovated , about 1990 I think and he was told it needed a tuneup.

someone else told him to try the Lucas additive and see what happens .

when that vehicle idles now you cant even feel it running and it is so smooth in acceleration and pickup its unbelievable .He never did get that so-called tuneup.

the engine is a GM 350 V-8

So I bought a gallon of it just to see if it would make a difference in my `02 -4 cyl .Camry.60.000MILES.

After the third tankful of gas I noticed improved acceleration and gas mileage, quieter running at highway speeds and no vibration at all at idle

I now use 100 ML per tankful. and would`nt be without it

And NO I AM NOT A DEALER OR AGENT FOR LUCAS.~!!!!!!!!

I don't know if its the best, but this is the one I use :

I've used the Techron few and far in between (4 bottles for about $10 at Costco). But the suggestion of Lucas sounds interesting. I'll give it a try too.

As far as the timing belt mentioned, the 4cyl doesn't have an automatic tensioner, so an old T belt can stretch and slack around, delay timing by just a couple of degrees and may give the belt back a shine.