hey everyone i need help big time i'am at the end of my rope as well as having the 2.0 si i have a family car for my little family a ST170 Focus on a 02 plate i have a miss fire on cylinder 4 i have changed the plugs, HT leads and the coil pack and pluged it in and it still missfires and say its on number 4 so i did a compression test and it has come out fine and i have checked the resistance on the injectors and thats fine. the reason i need help quick is cos the M.O.T has run out and i have had it tested and it faild on the emissons due to this problem pardon my french but what the f*ck can i do plz help

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Si 2.0 16v cheap and fast why not

have you tried it with the MAF plugged in?

slightly different to a 2.0 Fez, but its a start

other than that i have no idea

tried it m8 cheers any way don't know what to do

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Si 2.0 16v cheap and fast why not

i might of missed it but have you managed to stick her onto a diagnostic machine?

CPS sensor going duff?

Plug gaps correct? that would cause an issue.

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Daily isn't so Special. And it makes me sad.
Need space and time and I'll crack on with Jams si!

Catch me on Facebook as I'm rarely on here.

no sure m8 this car is just pissing me off why can't things run smooth. plugged it in (on slack) and all it said was missfire on cylinder 4 m8 but to me the sparks from the plugs seems shit what could that mean never come across something like this before cheers

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Si 2.0 16v cheap and fast why not

the ht lead mite be a unlucky duff

the carbon may have broken down before you even brought them

try and swap the cyliner 4 ht lead with the cylinder 3ht lead

and see if it says misfire from cylinder 3

that way you will no it its a duff lead

happend to me 1yr ago unlucky and rare for it 2 happen