Dan140

Yep that’s your air intake pipe. Should be a cheap part and something you/you and a friend could fit easily yourselves to save on labour. Definitely worth getting it fitted as you’ll be drawing air directly from the hot engine bay which will reduce the performance of the engine and may hurt your fuel economy as well. Dan

Just to chip in - got the bonnet up on mine after a drive today and it sounds the same as your recording, so think you’ve nothing to worry about - just the nature of the engine!

Yes you are right. I guess the addition of counter-weights to unbalance it makes the flywheel slightly heavier than normal but not clear if it's the additional weight or the inherent unbalance that is the cause of the rev holding. In any case, some more info on how Ford engineered the 1.0 and overcame some of the engineering challenges with a 3 cylinder here, interesting read! http://www.wardsauto.com/technology/ford-s-3-cyl-ecoboost-delivers-goods

Indeed! There's a lot more to 3 pots than simply chopping a cylinder off. The ecoboost is actually remarkably refined given the above, ford really did a good job with it. It's also interesting that to counter the vibration they usually have to use a heavier flywheel on 3 cylinder engines. One of the complaints I've read about (and experienced) is a tendency for the 1.0 to hold onto revs when changing gear at high rpm, and this is the reason why.

3 cylinders will naturally have more vibration than a 4 cylinder that you are perhaps used to (you might have a dodgy engine mount if it's noticeably very bad but I doubt it on a 1 year old car). I was going to have a go at explaining why myself, but this article does a much better job and has nice graphics to illustrate the point: https://www.carthrottle.com/post/heres-the-problem-with-three-cylinder-engines/ The key point is really the following: "An inline three-cylinder engine is essentially a straight six engine lopped in half. Normally in a straight six, the two outer cylinders reach top dead centre (TDC) in unison, with the other four cylinders reaching specific angles of rotation to balance the primary forces, secondary forces and rotational torque of the engine nicely. In a three-pot, piston one (the front piston) reaches TDC while the other two are 120 degrees away from either TDC or bottom dead centre (BDC). This means that the primary and secondary forces are balanced vertically, but the torque over the reciprocating pistons is not matched in unison like in an I6. Instead, the engine is trying to naturally rotate and flip over on itself. So to avert this, a balancing shaft is needed to counteract the twisting force. The torque inbalance (shared with inline-five engines) makes for a rattling powertrain as the engine tries to rock from end-to-end, even when balanced as much as physically possible. This is due to the weight of the balancing shaft that the crankshaft has to work against, making these engines less free-revving than their more-balanced counterparts. Counterweights can also be machined into the crankshaft itself but they also add weight, decreasing its ability to rotate freely. Also, due to the fact that ignition occurs every 240 degrees, the crankshaft journals are spaced 120 degrees apart. This means that there will be a significant proportion of crankshaft rotation (60 degrees) when no power stroke is occurring. That reciprocatory feature leads to the lack of smoothness in power delivery and large amounts of vibration that three-cylinder engines are notorious for. The rough-running engine behaviour will be emphasised at lower engine speeds especially, due to the lack of power strokes occurring."

Awesome mate, think you've made the right choice! For me it was a case of I needed 5 doors (the MK7 STs only ran for 1 model year with 5 doors so it's near impossible to find them) and the ride would have driven me a bit mental over all the speed bumps in Southwark (well, I would have sucked it up but the missus would have murdered me!). I've been deeply impressed by the ST line so far, the handling is awesome and the engine is meaty enough for most situations. I think it just goes to show what a well sorted chassis the Fiesta has. Hope you enjoy your ST when you get it! :) Dan

Loving it, cheers! Can't say I've really noticed but I came from a Yaris T-sport which has a notoriously clicky/rough 1.5 naturally aspirated engine so it might be a matter of perspective. I'll run it at idle soon and have a closer listen. Most engines sound a little rough when started up cold but should be reasonably smooth once up to temp. It's worth pointing out the 1.0 ecoboost is a pretty amazing engine and is relatively complicated compared to your average 4 cylinder motor, so that could account for some unusual/interesting noises.

It's a recirc valve but the noise definitely isn't synthesized as it's a heck of a lot louder with the window open! As I mentioned in another thread just now, the 140 ecoboosts run in excess of 20psi of boost so that's a lot of pressure to release when you lift off the throttle. Even with a recirc valve you can hear that air moving when the valve opens. As far as I am aware no OEM currently uses a true BOV as recirculating dump valves are quieter and better for the turbo/engine. Most fitted in the after-market are done for the noise rather than any real performance benefit vs. an uprated recirc valve.

Agreed, clearly audible on my 140 ST line if you lift off/change gear under hard acceleration. Given these engines are running ~20+psi of boost (I believe) I'd be surprised if you couldn't hear it even if it is a recirc rather than a BOV. And yeah, the ST Line is not a real ST, doesn't mean it isn't a damn good car. I got a thumbs up from a guy in a MK7 ST on Saturday, and felt a bit sheepish wondering if he knew I was an imposter. 😄

Was driving with the windows down on mine all weekend and can't say I noticed a "buzzing" noise. The whistling noise Eric described sounds like it just the turbo spooling up which is perfectly normal but I wouldn't think to describe that as a buzz. If you could get some video of it for us to compare it to that would be useful! I will keep an ear out when I take it for a drive next.

Ok so I would definitely advise getting a full service done as a first course of action, old spark plugs/blocked up air filter could definitely cause the hesitation you describe. I would also make sure that you are using a good fully synthetic oil that’s the correct viscosity as defined in your owners manual (likely 10W40 but check to be sure). I’d ignore the fuel advice as although supermarket fuel is allegedly not as good as Shell/BP, we’re not exactly talking about a high strung racing engine here (98 octane super unleaded would be a total waste of your money to be honest). Air mass sensor is definitely another possibility and an easy fix - I’ve not done it with a fiesta but they are usually easy to remove and you can get some electrical cleaner to sort that. Bet there is a YouTube tutorial somewhere. You said you do a lot of short trips which can cause the catalytic converter to become bunged up and again, give you the issues you describe, but this would be lower down my list of possible causes as you would likely throw an engine warning light (but not definitely). If all that doesn’t help...well it may be that it’s actually fine and you need a motor with a bit more poke! I will say that the old school automatics as found in your car can feel incredibly lethargic and I’ve found you have to floor and rev the nuts off them to achieve a respectable rate of acceleration. Hope you get it sorted one way or another!

OP - how long have you had the car? Is this a recent issue or has it always been this way? Sounds almost like the car is in limp mode but I would expect you would have a warning light of some kind if that was the case. Your bio says Fiesta Zetec which would suggest to me it is the 1.4 petrol with 95bhp, if my googling is correct. 95bhp *should* be plenty enough to prevent you struggling up hills and accelerating over 50mph. The 4 speed automatic which will be longer geared than a 5 or 6 speed manual (so you get less acceleration) probably doesn't help matters but what you describe sounds like you are missing a big chunk of power. It may be wise to take it to a Ford dealer and see if they can find any fault codes. They may be able to reflash the ECU to reset it which often solves problems. I presume you changed spark plugs etc. when it was serviced? Injectors are a possibility, but anyone trying to diagnose online will be speculating really.

Exactly the same as my experience! The refinement difference is actually laughable. I used to joke that the Yaris had a built in speed limiter at 70mph as anything above that on the motorway and it sounded like the engine was about to explode (think 80mph was 4k rpm which is just insane!). And you are right about the handling, the Yaris used to go very light at the rear end when cornering at any sort of speed which was at times amusing but often quite terrifying. The Fiesta is just so planted and doesn't jump around if you hit a bump mid-corner. Hope you continue to enjoy the Fiesta!

So still loving the little Fiesta, and starting to push it a little bit harder. All I can say is, what a well sorted chassis - it just grips and grips and grips; the new ST with the quaife diff must be awesome. Case in point: I was on a slip road that was two lanes on a tight left hand bend which merge into one before joining the dual carriageway. I was in the inside lane accelerating gently in 2nd gear when I saw a BMW coming relatively quickly in the outside lane. Wanting to avoid us both trying to merge at the same time into the single lane (and taking the view that being a BMW driver he probably hadn't noticed the signage), I decided to floor it and get there ahead of him. Well off I went, pulling some quite amusing lateral g without even coming close to overwhelming the front tyres. I saw the Bimmer give a little tail wag so presume he booted it as well but had to get out of it as I went off like I was on rails. Once onto the carriageway, he came flying past me which is when I realised the little ecoboost had managed to (briefly) show a clean pair of heels to an E92 M3. :D

I haven't seen anyone who's remapped a MK8 yet. From what I've seen of the MK7's, you can get 155-160hp out of the 1.0 with a remap. Easiest way is probably with a Bluefin (by Superchips). Costs about 350 quid, and you can do it yourself (and undo it yourself). Without changing other components you won't get a lot more with a custom map so in terms of £ per HP, this would be the way I would go. Obviously you have to consider the warranty/insurance implications as well.