Hi all im wondering if you guys can help please. I have a 2008 ford fiesta 1.6 tdci when vehicle hot and driving it momanterily drives on its own engine changes tone to be pinking and accelerates and when up to running  temp after this it cuts out and ideas i have look through forums but noone has a solution 

Many help much appretiated

Guessing noone has any ideas

2 hours ago, C.Goz said:

Guessing noone has any ideas

Give it time bud. Good people on this forum someone will help you soon 👍

On 5/15/2018 at 10:40 PM, C.Goz said:

have a 2008 ford fiesta 1.6 tdci when vehicle hot and driving it momanterily drives on its own engine changes tone to be pinking and accelerates and when up to running  temp after this it cuts out

You might have to describe the situation in a bit more detail.

For instance, if this happens when slowing down in a high gear, as the engine approaches idle rpm, it is normal to feel a small power surge as the ECU idle control kicks in. It is quite noticeable on a diesel due to the high torpue available at low rpm.

If it is when the engine is normal speed, then I suggest first change the oil & filter. Also often check if the oil level changes, up or down. Though this must be done at the same conditions each time, ie vehicle flat, or always in the same location if on a slight slope, and after it has fully cooled following a decent run where it got properly up to temp. Short cold runs can leave oil high up in the engine, making it look lower on the dipstick.

Also look for any black smoke from the exhaust when accelerating.

If it happens rarely, like over 100 miles between events, it could be a DPF regen starting, a normal event on the 1.6.

Diesel runaway is rare, but possible. However, firm braking will always beat the engine and bring the car to a rest, unless the brakes are totally shot, of course.

Hi peter many thanks for reply. Regularly serviced.only on 90k miles. Its completly random but all i no is engine has to be hot and outside temp has to be hot. Its not scavaging on oil. Black smoke comes out the exhaust when it does it. If it makes and difference it will idle all day long just under load (driving) the problem starts

 

4 hours ago, C.Goz said:

Its completly random but all i no is engine has to be hot and outside temp has to be hot. Its not scavaging on oil. Black smoke comes out the exhaust when it does it.

If the car has a DPF, then this would be my first suspect area. At 90k, if it is the original DPF, or a cheaper replacement one, then it is likely to be at the end of its life. Regen attempts become more frequent. The injector firing pattern alters for a regen, to put more fuel in to heat the DPF up. The engine note will change, and there may be a small change in apparent power. If the DPF is damaged, then black smoke is likely.

A DPF regen should only start when the engine is hot.

A diagnostic system like Forscan can monitor the DPF system, and find error codes that other systems do not see. The DPF system includes the DPF, a pressure (DP) sensor, one or two exhaust temperature sensors, and the Eolys additive system. The EGR valve and one or two throttle valves in the air intake are also involved. So it is quite complex.

Early Fiestas did not have a DPF, if I recall, but I suspect it was introduced at some stage.

Alternative problem areas might be a sensor like the MAF, that is misbehaving when its temperature goes above a certain point. If it reads wrongly, then it is possible for too much fuel to be injected.

On servicing for the 1.6TDCI, many people think the Ford standard interval is too long for oil changes, especially as the engine ages and wears a bit. It is very prone to carbon build-up inside. 6k miles or 6 months is often recommended.

 

2008 Fiesta will not have a DPF, it was added to the 1.6 TDCi mid 2010.

Alex is right myn does not have a dpf so drove it last night to get it to play up so i could get some readings. But it completly stopped come to start it now diesel knocking like mad with missfire. All injectors changed and been tested changed ecu (to a known good one) new fuel filter. Checked timing. What can corse it to over fuel. Still no codes

Also changed regulator on back of fuel pump.do you think its worth changing pump at all? I dont think it will do anything as its high preassure pump and surely it would log a code as fords are good for that

Egr is writen out whem we had remapped and also blanked