AberFowl Posted June 8, 2016 Report Share Posted June 8, 2016 Have a wee ford focus st170 to chug about in at present. When shes sat still I put pedql to metal and it sounds like a dump valve, its either releasing or sucking a breath of air really quick then revs climb but juddery... On the road it has a sweet spot but if I put the accelerate down abit more its awful juddery. Put pedal right to floor and revs drop, car coasts along and conks out! Any ideas?? Car has been sat in a dry garage for last year or so. Quote Link to comment Share on other sites More sharing options...
TaxiDriver Posted June 8, 2016 Report Share Posted June 8, 2016 Put some fresh petrol in ? Possibly coil pack breaking down under load ? Quote Link to comment Share on other sites More sharing options...
spandit Posted June 9, 2016 Report Share Posted June 9, 2016 +1 on the fresh petrol. Change the filter too Quote Link to comment Share on other sites More sharing options...
wymberley Posted June 9, 2016 Report Share Posted June 9, 2016 Thought at first you'd posted this in the wrong place as it sounds like me first thing in the morning. Could be the coil but sounds more like fuel starvation. Filter? Crud in tank? Tank filler cap breather blocked is not unheard of? Or distributor advance/cam dwell possibly? Quote Link to comment Share on other sites More sharing options...
Paul223 Posted June 9, 2016 Report Share Posted June 9, 2016 As above but also is it turbo charged (sorry I don't do petrol cars) if so check boost pipes for splits Quote Link to comment Share on other sites More sharing options...
Hendrix's rifle Posted June 9, 2016 Report Share Posted June 9, 2016 (edited) The st170 has flaps in the intake manifold controlled by a motor, if the motor goes down the flaps like to stay closed therefore allowing no air into the engine. I have seen this a few times and it is similar to what you have said. However, I would pull the fuel filter and replace it and change the coils and plug incase the coils are breaking down. Good luck 👍 Edit - fill the tank with high octane aswell Edited June 9, 2016 by Hendrix's rifle Quote Link to comment Share on other sites More sharing options...
Gordon R Posted June 9, 2016 Report Share Posted June 9, 2016 ST170 doesn't have a turbo. Quote Link to comment Share on other sites More sharing options...
Cannon Posted June 9, 2016 Report Share Posted June 9, 2016 Unplug your MAF sensor beside the airbox then take the car for a spin. See if it makes a difference Quote Link to comment Share on other sites More sharing options...
jonny thomas Posted June 11, 2016 Report Share Posted June 11, 2016 Sounds like maf to me check spark plug people tend to forget cars still have spark plugs if its the ford engined model (as in not volvo ) The spark plug tubes have a habit of filling up with water /oil If thats the case change plugs and leads ps fords like ngk plugs dont know why they just do Quote Link to comment Share on other sites More sharing options...
AberFowl Posted June 11, 2016 Author Report Share Posted June 11, 2016 Ngk platinum plugs put in along with new leads and coilpack.... Car ran fine for a good 100mile today then started juddering again and got worse as I went along. Juddery under acceleration, completely cuts all power when foot put right down. Fuel starvation!? Changing oil filter and oil and fuel filter tomorrow and going to throw in some of that redex engine cleaning stuff...see if that makes a difference. Failing that I guess it will be a new fuel pump!? Cant see any damage to any air pipes, maf unplugged for a good few miles and no difference felt/hears Quote Link to comment Share on other sites More sharing options...
jay404 Posted June 11, 2016 Report Share Posted June 11, 2016 Either maf sensor or un-monitored air entering the combustion cycle putting the mix all out Quote Link to comment Share on other sites More sharing options...
Paul223 Posted June 12, 2016 Report Share Posted June 12, 2016 Again I don't do petrols... does the crankcase breather enter the metered air? Is that breather all as it should be? Quote Link to comment Share on other sites More sharing options...
Royboy Posted June 12, 2016 Report Share Posted June 12, 2016 I'd say MAF sensor as already said, try unplugging it and see if it improves Quote Link to comment Share on other sites More sharing options...
Rst1990 Posted June 12, 2016 Report Share Posted June 12, 2016 Buy a fault code reader it will tell you exactly what the problem is. Quote Link to comment Share on other sites More sharing options...
AberFowl Posted June 12, 2016 Author Report Share Posted June 12, 2016 Unplugged maf sensor and drove it a while. No different to with it plugged in. Car parked up overnight and drove it this morning approx 25miles, running fine!? So problem is clearing itself when car sits then reocurring during longer journeys. When the car is sat in neutral it revs up and down absolutely fine, no juddering or spluttering... Ita only doing it when car been driven Quote Link to comment Share on other sites More sharing options...
Royboy Posted June 12, 2016 Report Share Posted June 12, 2016 Oh right sorry I didn't realise it revved up fine when stud still, that won't make it a MAF fault. Quote Link to comment Share on other sites More sharing options...
Hendrix's rifle Posted June 12, 2016 Report Share Posted June 12, 2016 Unplugged maf sensor and drove it a while. No different to with it plugged in. Car parked up overnight and drove it this morning approx 25miles, running fine!? So problem is clearing itself when car sits then reocurring during longer journeys. When the car is sat in neutral it revs up and down absolutely fine, no juddering or spluttering... Ita only doing it when car been driven Sounds electrical, sounds like something is breaking down under load, just have to try and find it Have you checked/tested the fuel pump? Just to rule that one out? Is there any funny noises on startup? Quote Link to comment Share on other sites More sharing options...
philm Posted June 13, 2016 Report Share Posted June 13, 2016 Have you tried the cam sensor. Quote Link to comment Share on other sites More sharing options...
Paul1440 Posted June 13, 2016 Report Share Posted June 13, 2016 (edited) Coil pack. If you can get hold of a code reader it will tell you whats wrong. They are just about as cheap to buy as what a garage will charge to plug theirs in If it is a coil pack. Get one off Eurocar parts or a similar outlet.. they are easy to change and you can do it at a fraction of the cost of taking it to a garage. See Ford forums on interweb. Edited June 13, 2016 by Paul1440 Quote Link to comment Share on other sites More sharing options...
Hendrix's rifle Posted June 13, 2016 Report Share Posted June 13, 2016 Coil pack. If you can get hold of a code reader it will tell you whats wrong. They are just about as cheap to buy as what a garage will charge to plug theirs in If it is a coil pack. Get one off Eurocar parts or a similar outlet.. they are easy to change and you can do it at a fraction of the cost of taking it to a garage. See Ford forums on interweb. He has put a coilpack in it along with plugs and leads Quote Link to comment Share on other sites More sharing options...
Royboy Posted June 13, 2016 Report Share Posted June 13, 2016 Does it smoke at all ? Maybe dodgy fuel ? Quote Link to comment Share on other sites More sharing options...
HAYBURN Posted June 13, 2016 Report Share Posted June 13, 2016 Why did you change the plugs,leads and coil pack ?? did it have the same fault before you changed those parts I'm not sure, in between the spark plug holes is there not screw in core plugs I'm sure I changed or resealed them on a vehicle as coolant was getting to leads an plugs causing a short.. Quote Link to comment Share on other sites More sharing options...
AberFowl Posted June 14, 2016 Author Report Share Posted June 14, 2016 Why did you change the plugs,leads and coil pack ?? did it have the same fault before you changed those parts I'm not sure, in between the spark plug holes is there not screw in core plugs I'm sure I changed or resealed them on a vehicle as coolant was getting to leads an plugs causing a short.. As stated, they were changed due to this problem but did not cure it. Quote Link to comment Share on other sites More sharing options...
philm Posted June 17, 2016 Report Share Posted June 17, 2016 Give us a clue, what was the fault? Quote Link to comment Share on other sites More sharing options...
mrwabbits Posted June 17, 2016 Report Share Posted June 17, 2016 (edited) Sounds like fuel pump issue, the pickup pipe has a tea bag type filter on the end of it. These OE fuel pumps are well known to breakdown and cause fault. The fact you say its ok standing still but then creates when driving - fuel slosh /crud in tank and the pump cant cope in sucking up the fuel during motion. . I appreciate the value of expenditure you are laying out in order to resolve the problem , but, try going for an up-rated fuel pump and clean the lines out and replace the fuel filter/s when/if you fit a new pump. cheaper than an oe dealer prices and can cope up to 300 bhp . . Its a sytec intank pump, you can buy this uprated pump direct from pumabuild online. about £105.00 . . If you havent done so already, do an OBD2 code read and note down any/if fault/s codes thrown up and reset , just incase it throws up a lambda /maf sensor fault , but i doubt it - Worth buying or borrowing an Autel MaxiScan OBD2/EOBD reader, with this you can read info` and do a live run monitor check with it still plugged in - and yes you can check the mph reading too - just scroll through the menus. .Alternatively - purchase a plug-in bluetooth OBD2 adapter and download one of the free OBD2 smartphone app`s. Easier with a generic Android smartphone, as iphone`s dont like the adapters (iphones are very choosey on what bluetooth items they will connet to). Just remember to make sure the Ignition is OFF when you plug in and unplug. . If its the lambda sensor - £78. off amazon hth Edited June 17, 2016 by mrwabbits Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.