I asked a simaler question on the rs turbo page but i was just wondering if iv melted a piston/pistons (not sure if i have) wouldn't it run like shit in nutral coz it runs fine in nutral it revs up nice all the way to 7000. But when im driving soon as the car starts to boost quite strong it goes all crackely and flat. I haven't looked at the revs but it must start about 4000 revs onwards . I know it needs a set up but will this happen with a melted piston.
It runs fine in nutral and not when driving it doesn't sound right to me. im not saying i have one but is it possable?
the car is a escort 2s

 

If you had a melted piston it would only run on three cylinders.
and on a S2 it would blow the oil filler cap off


Dave

 

should you really be running it at 7000 rpm before it has been set up?

 

it was only flicking it up to it i wasn't holding it there i had to see if it done it in anywere in neutral and i didn't

 

do a compression test and this will tell u if there is any probs with ur bottom end

has it just happened or has it always been like this? have u checked the timing have u changed anything lately

if its holding back it could be timing or/and fuelling

 

when i bought the engine the breather on the left hand side of the rocker had zip ties holding it together so im gessing it was poping off.
so if i had a piston down it would definutly be running on 3?

 

yes