focus st3
Thread Starter
Virgin
Joined: Jan 2019
Posts: 3
Likes: 0
From: Bishops stortford
focus st3
Hoping someone can help currently have a focus st3 on the odd occasion while driving it has a hesitation for couple of seconds has a flat spot but if u keep your foot down it clears and pulls fine. Also when it does this the boost gauge drops and once it’s had its moment gauge comes back to normal when I first got the car it done it but recently getting more frequent. It’s almost like a misfire like it drops a cylinder. It’s had new plugs someone scanned it and came up with mass air flow sensor which was changed but still doing it. I’m hoping someone can point me in the direction of what it can be as at the moment spending money on it I haven’t got.. many thanks in advance..
Rs turbo
Joined: Dec 2018
Posts: 306
Likes: 23
From: Kidderminster
Hi mate could be a number of things. As you counted out two things. Look to see if there is a vacuum leak. Could be TPS maybe coil. Also a bit more in-depth could be that the injectors are clogging up so not giving a fine mist as it should.
Thread Starter
Virgin
Joined: Jan 2019
Posts: 3
Likes: 0
From: Bishops stortford
it was ran on live data injectors were checked and all came back OK it put on dyno last week and was recently remaped and seems to be doing it more frequent since remap ?
cossie fan (unluckerly)
Joined: Nov 2009
Posts: 9,798
Likes: 435
From: hampshire
I had this like a low down miss as it was building boost or held at a low boost level. If you held it flat out it would clear. I fitted new plugs and a boost solenoid and it’s fine now. Mine had no warning lights or stored errors so was a case of trying bits lol
Last edited by ajamesc; Jan 30, 2019 at 08:58 AM.
Gary Krishna
iTrader: (9)
Joined: Mar 2008
Posts: 4,029
Likes: 67
From: Rickmansworth, Hertfordshire.
I did reply saying try plugs first then reread it and saw you'd changed them! 
I would say it's likely to be an ignition coil tbh.
I would say it's likely to be an ignition coil tbh.
Last edited by Gazzonator; Jan 30, 2019 at 08:58 AM.
Thread
Thread Starter
Forum
Replies
Last Post
#13
General Car Related Discussion.
46
Apr 3, 2006 11:14 PM