Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently

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Fri 18 Jul 2014 06:49
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - wayward vortex

OK so I just got a new head gasket and cambelt put in, new radiator, thermostat housing, water pump and expansion tank for the cooling system too. I thought the car should be spick and span after all this, but no. When I have to slow down rapidly and drop gears, or go straight into neutral, the engine simply stops and I have to restart it with my foot on the accellerator pedal (I have to cold start it like this too). The garage that did the work said to bring it in if there were any problems and they will sort it out complimentarily, so I am not too distraught yet. I can prevent the stalls if I can anticipate the speed changes and slow down gently so it is just about good for work today. It will be back at the garage tomorrow.

Any ideas anyone? I hear of vacuum leaks, idle rev speed control, or even faulty spark plugs (quite likley after head gasket issues maybe)! Does someone know specifics for my engine type?

Cheers!

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Fri 18 Jul 2014 09:47
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - elekie&a/c doctor

If the head has been off,then all the connections to the engine fuel injection system need to be checked.Make sure the contacts are clean and tight.Also the air inlet throttle housing and idle control valve must be clean.Very unlikely to be spark plugs but certainly check all vacuum and air inlet pipework for leaks.

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Fri 18 Jul 2014 23:04
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - wayward vortex

Ok cheers! Will be sure to check what the garage check against this checklist ;()

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Sat 19 Jul 2014 14:44
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - wayward vortex

Turns out it was the fuel inlet valve (is this right?)!! I guess the head gasket leak could have rendered this a casualty?!?

All I need to do now is find a replacment.... Been to a few breakers yards altho they didn't stock any... Vospers want £25.

Can I get a confirmation for what the part is called as I cant see anything on the internet and this seems unlikely?? Its right next to the spark plugs and if U pull out a vacuum tube the engine revs fine, altho when it goes back on, engine cuts out when revs drop!?!

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Sat 19 Jul 2014 16:33
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - elekie&a/c doctor

Never heard of a fuel inlet valve.Whatever it is,I doubt if this is the problem.

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Sun 20 Jul 2014 07:23
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - wayward vortex

If we assume the part that malfunctions here is not a fuel inlet valve....

What can we call the part that sits next to the spark plugs, has a vacuum tube that one can easily pull off and find that when it is off the engine revs fine, and then when reconnected causes the enine to cut out after it revs up high, and then is allowed to drop revs quickly???

Edited by wayward vortex on 20/07/2014 at 07:24

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Sun 20 Jul 2014 09:47
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - jc2

The name of this device is "fuel pressure regulator"-it is clipped on this engine to the end of the fuel rail that supplies the injectors.It's purpose is to control the flow to the injectors to match the engine's needs and that is why it is connected to the inlet manifold.At idle(high vacuum)it will resrict the fuel flow and will gradually open as manifold vacuum decreases.It is possible that this was damaged during work done on the engine-it's plastic on this model.

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Sun 20 Jul 2014 10:59
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - wayward vortex

I think thats it : FUEL PRESSURE REGULATOR VCV (VOLUME CONTROL VALVE)!

Cheers!

Edited by wayward vortex on 20/07/2014 at 11:00

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Sun 20 Jul 2014 11:11
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - elekie&a/c doctor
I would suggest you get the fuel pressure tested before changing this part.
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Tue 22 Jul 2014 19:09
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - wayward vortex

OK so I had already put in an order when I read this message on Monday evening so I just went through with it and picked the part up from Vospers today. Went to my garage and they hopefully fitted it with a smile and off I went, equally hopefull.

... it still cuts out :()

Does this mean the old fuel pressure regulator was fine? Or does the engine need time to unify with it, and get its fuel pressure back to equilibrium?

Cheers!

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Fri 25 Jul 2014 18:00
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - wayward vortex

Ok so I spoke to someone who runs a mobile diagnostic service today and he told me for free the problem I have has always in his experience been the throttle body, and the idle control valve, as was at first said here, by eleky&a/c :()

Lesson to be learnt here is dont trust b***** computers to identify faulty parts!!!

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Fri 8 Aug 2014 18:47
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - wayward vortex

Ok so the lesson is now triple learnt and the fault persists with no diagnostic....

I got two other garages to diagnosehe issue.They seem to only have the computer up their sleeve. The first did not charge. The second, Vospers, did charge me and have given me a vehicle health check for the half hour I paid for, rather than get their hands dirty.

All I now know is this fault is not showing up on the computers as such methods of diagnosis turn up a blank. Vospers' explanation is that the previous garage wiped the codes, although they must have known te issue has been ogoing and therefore I have to deem them incompetant, and even untrust worthy.

Can anyone offer a diagnosis of the cut-out from high to low revs on the basis of it not showing on the machines? Surelythis means t is not a fault in the parts? Or some part of the engine that does not cause the computer to flag anything up?

Also, what should I expect from a garage when I tell them what is wrong with my engine and ask for a diagnosis? Is half an hour at a £50 rate (Vospers) not enough?

Cheers!

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Mon 18 Jan 2016 07:04
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - kimichamp1

Hi, I have the same problem with Fiesta MK5 1.4 Petrol
Mechanics replaced the pressure regulator (it was leaking petrol) however
the hose was not attached to it and the car worked. Only trouble, after initial warm up with automated idle, upon starting the drive, first 3-4 minutes, with each gear change, when gas pedal is released to shift gears, revs drop below 500 and engine stalls. If you "help" the engine holding gas pedal a little, revs stabilize. But sudden throttle and then pedal release, revs drop below line and engine shuts off. Later on when engine warms up, no problems.

When the vacuum hose is fitted back to regulator, engine dies with every gear change, no matter warm or not. Also computer check did not show much.

I dont know what is the problem. Mechanics also tried to change trottle body and clean the air flow sensor but it did not help. They thought it has to be something with LPG installation which is installed they think improperly.

But from this case I see it happens with purely petrol driven car.

Any suggestions please ?

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Sat 25 Mar 2017 16:34
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - gtomgee

hi did you guys ever find the solution to this problem?

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Sun 4 Jun 2017 05:27
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - Vit Adamek

Hi, I have similar problem. There is some front facing sensor on throttle body of my Mk1 1.4 2003 Focus. If I disconect the connector on that sensor while engine s running then the idle revs settle nicely and it does not cut out anymore, my friend thought that it is mass airflow sensor but I think it is somethink else. I am going to try to replace it and post some pictures or video of it later... Btw, did you find solution?

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Tue 3 Oct 2017 23:22
Ford Fiesta Zetec MK6 1.4 Petrol - Rapid decelleration cuts out engine silently - sam1990

Hi

Gunked up Idol control valve is a common fault on a mk6 1.4 petrol, eqally common is the vacum pipe to the throttle body, this pipe perishes (goes mushy or splits) if it goes mushy at idle it collapses causing hunting (engine starts fueling more to keep going, idol seems lumpy) similar or same symptoms for split pipe. funnily enough there is also a T peiced pipe conected to the ICV and it perishes and splits and also causes the problem described. If the one to the underside of the throttle body is perished it can appear fine, you really need to grab hold of it and feel if it has become soft anywhere. This part costs £11 new from fords(days) and is situated under the inlet manifold and apears to go from the crank case to the left under side of the throttle body. the one to the ICV also needs to be physically checked and when changing it spray some brake or carb cleaner into the union it goes to on the icv this should be enough to clean out the ICV at the same time. I hope this helps I seriously doubt it is anything more serious. There are a few common engine faults with mk6 fiestas most are cheap and easy to fix. Don't be milked by bad garrages.

Edited by sam1990 on 03/10/2017 at 23:36

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