So basically iv been repairing this fiesta planing to use as my daily don't 90% of the jobs now but for some reason it has a massive flat spot, it starts and revs freely until you dump your foot into the carpet it suck a shed load of air in and is very hesitant sometimes a small backfire to it's had a new cambelt plugs leads and coil

When I did the belt I used the correct tools and correct timing marks on the crank pulley with cams locked out, turns over by hand and everything lines up nicely

BUT when you start the car and point a timing gun at the crank the marks are out

I kno there is two marks on a pulley one directly down and one at 5 o'clock when I timed it, I did it to 5 o'clock but when it's running the mark directly down is lining up the with marking on the sump????

Any help is massively appreciated as my currently daily car runs out of mot end of the month and need the si sorting

Cheers guys

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Two videos

On one of them you can see the timing jump between tec and a few degrees out, both videos were taken from idle.

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Did this flat spot only start after you done the belt?
If so then id check the timing marks again at tcd with a long extention bar down cylinder 1 plug hole.
Its way to easy to use the wrong timing mark.
If its off you can just lock the cams in place slacken the sproclet bolts and spin the crank back to tdc with an 18mm spanner.

If the timing is correct then have you checked the maf sensor is clean?

On some cars you can unplug the maf and it will run open loop.
If it does go for a little test drive, if it runs better then the maf is your problem if it runs the same or worse then youll need to investigate the fueling (check the pressure, ensure the filters not partially blocked)

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buttery biscuit boost

Just watched your vid you used the notches on the edge of the pully for the reference marks not the drilled circles right?

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buttery biscuit boost

Iv since re done the timing and got it better but yeah I used the notches not the drilled holes aha now when I'm driving it will drive 'normal' fine and if i go easy on the throttle it will climb all the way up to redline but if I drive along at a normal pace and dump my foot it Boggs down and is very very hesitant, been busy recently so not had chance to mess with it but a fuel check is defiantly next

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