Ford Fiesta - Yellow warning light no fault codes

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Sun 8 Mar 2020 14:53
Ford Fiesta - Yellow warning light no fault codes - MommaD81

So we brought my son a 2008 fiesta. It is a 1.4 tdci. It ran fine for a couple of weeks and has now consistently started coming up with the message Engine system fault and runs very badly in Limp Home Mode. No fault codes come up on the dash.

We've changed fuel filter, and injectors and checked the EGR is not blocked and is functioning

Any one any ideas?

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Sun 8 Mar 2020 17:30
Ford Fiesta - Yellow warning light no fault codes - elekie&a/c doctor
The dash will not display the fault logged . You need diagnostic equipment to evaluate the problem.
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Tue 10 Mar 2020 18:25
Ford Fiesta - Yellow warning light no fault codes - MommaD81

We have an obd2 reader and it shows no faults

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Tue 2 Jun 2020 09:24
Ford Fiesta - Yellow warning light no fault codes - MommaD81

Ok we whittled it down to a misfire! We had all the injectors tested and brought 2 refurbished from a reputable company . Still misfires but now on a different pot. So hubby swapped injectors same pot still misfired. So now he has checked the wiring which all seems fine. We can't find anywhere to test the obscure ECU this car has. So now we are really stuck. Oh and still no codes

Any body got any ideas

Cheers

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Tue 2 Jun 2020 09:31
Ford Fiesta - Yellow warning light no fault codes - elekie&a/c doctor
Next step would be to do a cylinder compression test .
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Tue 2 Jun 2020 13:16
Ford Fiesta - Yellow warning light no fault codes - Gibbo_Wirral

Cheap ODB readers are sometimes useless and miss manufacturer specific fault codes.

You'd be better off using the proper Ford disagnostic equipment. Try asking on a Ford users forum, my brother has one for his Mondeo in Sheffield and helps others out.

Edited by Gibbo_Wirral on 02/06/2020 at 13:17

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Tue 2 Jun 2020 20:53
Ford Fiesta - Yellow warning light no fault codes - Railroad.

The presence or absence of fault codes proves nothing. The ECM will log a fault code if it receives information from a component which is outside of its programmed parameters. The engine could be running very poorly, but the ECM would not know that unless something told it.

An EOBD (known as OBD II in North America) scantool is only capable of reading engine emission related data. They cannot read manufacturer specific data or any other controller on the vehicle. This will be why you are not seeing any fault codes. The likelihood is they're present, you just cannot access them with the equipment you have.

You need to go to someone who does have a suitable scantool for your vehicle. Anything you do will be mainly guesswork which in the long term will probably prove more costly to you than taking it to a garage in the first place.

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Sat 6 Jun 2020 18:08
Ford Fiesta - Yellow warning light no fault codes - Big John

If bought from a trader why not take it back? If less than 6 months you have pretty good rights.

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