Ford Ka 2001 Endura engine - Ford Ka running rough

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Thu 22 Oct 2015 14:25
Ford Ka 2001 Endura engine - Ford Ka running rough - Devilka

Hi,

I have a problematic Ka. It starts fine and idles perfectly but once throttle opened it stutters and doesn't fire on all cylinders (both when stationary and under load on the road). When throttle returns to idle engine almost stalls and then after a few seconds it settles back to a good idle. If I open the throttle wide open (car stationary) engine will rev as you would expect. Again, when I back off throttle engine almost stalls then settles back to idle. I have done numerous tests to try and isolate the problem. Have replaced coilpack, new HT leads, tested injectors (perfect), tried a different idle control valve, throttle body, O2 sensor, throttle position sensor. Even tried a second-hand ECU. Even after all this there has been no change. Clearly I haven't nailed it. Someone suggested I may have a faulty crankshaft position sensor?? I hope someone out there may have experienced similar symptoms and most importantly has a solution to my issue. Thanks in anticipation.

Cheers

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Thu 22 Oct 2015 16:33
Ford Ka 2001 Endura engine - Ford Ka running rough - madf

Check fuel filter. When was it changed? All symptoms are of fuel starvation under load.

Air filter? Ditto check.

These are basics which you have not mentioned.

When was oil changed?

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Thu 22 Oct 2015 17:00
Ford Ka 2001 Endura engine - Ford Ka running rough - Railroad.

Clearly playing parts darts with this is getting you nowhere, and some of the parts you've changed were never going to cure your problem. Anyone could've told you that.

Start by using a vacuum gauge to check inlet manifold vacuum. This will tell you a lot about the running of the engine. Google how to use it and what to look for.

Use a scantool and do some live data checks. Pay particular attention to fuel trim. There is lots of information and tutorials on the internet.

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Thu 22 Oct 2015 19:01
Ford Ka 2001 Endura engine - Ford Ka running rough - elekie&a/c doctor

Forget all the electronic bolt-on bits,how about the basics?Valve clearances and a cylinder compression test would be a good place to start.

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Fri 23 Oct 2015 00:50
Ford Ka 2001 Endura engine - Ford Ka running rough - Devilka

Thanks for the advice guys. I should have added that I've changed filters, checked compression,valve clearances, fuel rail pressure and vacuum. All very good. Agree that it appears to be a fuelling issue however it will rev with wide open throttle with no apparent fuel starvation. So I think the basic mechanicals are fine but there is a control problem either fuel or ignition?

Cheers

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Fri 23 Oct 2015 13:50
Ford Ka 2001 Endura engine - Ford Ka running rough - Peter.N.

Have you changed the plugs? The problem could be low ignition voltage or to wide plug gaps, that's what it would have been on old fashioned engines anyway. Could be weak mixture when opening the throttle but unless it uses a carburettor I can't help you. The last petrol cars I had used carburettors, distributers and even dynamo's.

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Fri 23 Oct 2015 13:56
Ford Ka 2001 Endura engine - Ford Ka running rough - Railroad.
Ok so going by what you say it would seem that the engine itself is in sound condition. There are no intake vacuum leaks, the valves and piston rings are good, the exhaust is not blocked and the valve timing is correct. A vacuum gauge will indicate all of these.

Have you taken a sample of the fuel itself and checked for any sort of contamination such as water?

Also check the MAP sensor. It's job is to tell the ECM manifold vacuum, except they can't read vacuum, so it reads pressure. Since the manifold should have a vacuum of about 20 inches Mercury at idle the ECM will read this as a negative pressure, usually in KPa. About 40KPa (0.4 Bar) would be normal at idle. 100KPa or 1 Bar is atmospheric pressure at sea level, so expect a small variation in pressure depending on how high you are above sea level. Compare this reading with a scantool against what your vacuum gauge reads. If the readings are vastly different the MAP sensor is probably faulty, and this will have a more of an effect on fuelling than any other component of the system.
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