Engine Is Misfiring When Accelerating

[Chris Chopper]

My focus has started to stutter/misfire when I accelerate it only happens when in a low speed for the gear but normally the engine will handle it not a problem so for example 20mph in 3rd gear should be a problem accelerating up but the engine seems to stutter/misfire until the car is at a speed this problem is the same for all gears but 5th as the car speed is enough also fine in 1st again as the gearing is meant for that speed. can anyone advise please?

[salsheikh]

it could be a number of things Chris, best bet is to have the codes read for any faults that will be logged in the ECU.

[Chris Chopper]

Had the engine diagnostics check last night no fault codes showing, Was told it could be either the plugs,leads,MAF or coil went to Fords this morning to start with the lowest costing part (so I thought) and work my way up in costs but after chatting with the parts department they said it would be the coil pack which was also the cheaper part to replace, They said they don't keep leads in stock as they hardly ever need replacing so would be on order however they'd sold 4 coil packs already this year and normally sell 1-2 a month, The cost of the MAF sensor on my model was over £350 as it comes with the throttle housing and other bits?! So I changed the coil pack this morning and tested it out just now and all seems fine no misfiring under load whatsoever in any gear :-) Hopefully alls good as this is the first part I've had to replace (non service part) since having the car from new.

[ajzetecs]

have u got egr blank on, i had same problem, took blank off and was ok

[confederate]

dont get it my son had a misfire while driving in his 2005 focus,he had an oil changed and the misfire stopped

[Botus]

may be the rain around the spark plugs drained out whilst on a jack?