d Ka misfiring
Discussion
My Ford Ka is still misfiring...
I've just about checked/replaced everything obvious: coil, plugs, leads, TDC sensor, injectors. No leaks on intake manifold. Changed oil and added cleaning agent - no sticking valves. Compression OK on all 4 cylinders. No error messages on diagnostics port. 4 garages have looked at it and the general conclusion is: faulty ECU.
But I don't believe that, as I've read in several places that ECUs either work properly, or not at all, or go into some kind of safe idling mode.
Symptoms are:
perfect start on cold & no misfire even at full throttle, but after about a mile it misfires terribly, almost not possible to drive. Press the accelater a little bit and it misfires badly. Then, after a good half hour run, including a blast on the motorway, it gets better to the point that I can keep up with traffic in the fast lane, press the accelerator all the way down and there is no problem...
Thrn I leave it overnight, and it's the same story again.
What can it be? It must be something blindingly obvious, but I don't see it !?
Jim
I've just about checked/replaced everything obvious: coil, plugs, leads, TDC sensor, injectors. No leaks on intake manifold. Changed oil and added cleaning agent - no sticking valves. Compression OK on all 4 cylinders. No error messages on diagnostics port. 4 garages have looked at it and the general conclusion is: faulty ECU.
But I don't believe that, as I've read in several places that ECUs either work properly, or not at all, or go into some kind of safe idling mode.
Symptoms are:
perfect start on cold & no misfire even at full throttle, but after about a mile it misfires terribly, almost not possible to drive. Press the accelater a little bit and it misfires badly. Then, after a good half hour run, including a blast on the motorway, it gets better to the point that I can keep up with traffic in the fast lane, press the accelerator all the way down and there is no problem...
Thrn I leave it overnight, and it's the same story again.
What can it be? It must be something blindingly obvious, but I don't see it !?
Jim
I have had same simptoms on a customers car have you checked the multi plug on the ecu? these a prone for getting wet and corroding.
ecus can fail with out going into limp mode or resulting into a non start situation.
Misfires, high emmisions and stalling can be a result of ecu spikes or bad connections between the ecu and wiring loom.
The ecu on ford ka's tucked up behind the dash left hand side of n/s foot well check the plug and ecu for dirty or corroded pins if there are signs of corrosion cleen pins on plug and ecu. If this dose not work ecus can be refurbished for as little as £350 there are companys that will test ecus for such damage however ecu must be removed from vehicle
ecus can fail with out going into limp mode or resulting into a non start situation.
Misfires, high emmisions and stalling can be a result of ecu spikes or bad connections between the ecu and wiring loom.
The ecu on ford ka's tucked up behind the dash left hand side of n/s foot well check the plug and ecu for dirty or corroded pins if there are signs of corrosion cleen pins on plug and ecu. If this dose not work ecus can be refurbished for as little as £350 there are companys that will test ecus for such damage however ecu must be removed from vehicle
Keith thanks for your reply.
I have checked the ECU before ( by looking at it) and it seems clean and dry. But I have not taken the plug off. I will do that when I get home on Friday.
The ECU is in an awkward place and it looks like quite a job to remove it.
Since my last post I've established beyond doubt it is an ignition issue: on tick-over misfire is mostly in cylinders 2 and 3 (which fire as a pair of course). When I replace the (LPG) injector 2 plug with that of no 4, and the no 3 by no 1, the misfire is still mostly on cylinders 2 and 3... (checked by sequentially removing each of the injector plugs).
(by the way as explained previously, the LPG installation is absolutely ruled out as the cause)
If it is the ECU, I won't bother replacing it, and will scrap the car. It a 2004 Ka, but has 193,000 miles on the clock. It doesn't owe me a thing but I'll be sad to see it go...
I have checked the ECU before ( by looking at it) and it seems clean and dry. But I have not taken the plug off. I will do that when I get home on Friday.
The ECU is in an awkward place and it looks like quite a job to remove it.
Since my last post I've established beyond doubt it is an ignition issue: on tick-over misfire is mostly in cylinders 2 and 3 (which fire as a pair of course). When I replace the (LPG) injector 2 plug with that of no 4, and the no 3 by no 1, the misfire is still mostly on cylinders 2 and 3... (checked by sequentially removing each of the injector plugs).
(by the way as explained previously, the LPG installation is absolutely ruled out as the cause)
If it is the ECU, I won't bother replacing it, and will scrap the car. It a 2004 Ka, but has 193,000 miles on the clock. It doesn't owe me a thing but I'll be sad to see it go...
Jim1064 said:
Keith thanks for your reply.
I have checked the ECU before ( by looking at it) and it seems clean and dry. But I have not taken the plug off. I will do that when I get home on Friday.
The ECU is in an awkward place and it looks like quite a job to remove it.
Since my last post I've established beyond doubt it is an ignition issue: on tick-over misfire is mostly in cylinders 2 and 3 (which fire as a pair of course). When I replace the (LPG) injector 2 plug with that of no 4, and the no 3 by no 1, the misfire is still mostly on cylinders 2 and 3... (checked by sequentially removing each of the injector plugs).
(by the way as explained previously, the LPG installation is absolutely ruled out as the cause)
If it is the ECU, I won't bother replacing it, and will scrap the car. It a 2004 Ka, but has 193,000 miles on the clock. It doesn't owe me a thing but I'll be sad to see it go...
Having read your last post on this fault, some other possibilities spring to mind.I have checked the ECU before ( by looking at it) and it seems clean and dry. But I have not taken the plug off. I will do that when I get home on Friday.
The ECU is in an awkward place and it looks like quite a job to remove it.
Since my last post I've established beyond doubt it is an ignition issue: on tick-over misfire is mostly in cylinders 2 and 3 (which fire as a pair of course). When I replace the (LPG) injector 2 plug with that of no 4, and the no 3 by no 1, the misfire is still mostly on cylinders 2 and 3... (checked by sequentially removing each of the injector plugs).
(by the way as explained previously, the LPG installation is absolutely ruled out as the cause)
If it is the ECU, I won't bother replacing it, and will scrap the car. It a 2004 Ka, but has 193,000 miles on the clock. It doesn't owe me a thing but I'll be sad to see it go...
1/ Worn camshaft lobes.
2/ Valve recession to such an extent that correct valve clearance is outside the range of the hydraulic lifters.
Thanks Keith. I checked the ECT sensor. It has just two wires which, when diconnected from the sensor, have 5 volts across them. I measured the resistance of the ECT sensor: 55 kohm/cold, 10 kohm/handwarm, 2 kohm/hot. I don't unbderstand the autodata info, but these changing resistance values indicate to me that the sensor is OK.
The garage checked the oxysensors, by replacing with used ones that were known to be OK - again no problems here.
I tried to get the connector off the ECU to check for corrosion, but could not get it off. But I don't believe there could be corrosion, as the ECU, cable and connector, and surrounding steel surfaces seem all very clean and dry. There is no water there...
So, it must be the ECU....Or the valves...
The garage checked the oxysensors, by replacing with used ones that were known to be OK - again no problems here.
I tried to get the connector off the ECU to check for corrosion, but could not get it off. But I don't believe there could be corrosion, as the ECU, cable and connector, and surrounding steel surfaces seem all very clean and dry. There is no water there...
So, it must be the ECU....Or the valves...
I've just done a test drive with injectors 2 and 3 disconnected.
Result: the backfiring stops completely and cylinders 1 and 4 run OK (lumpy but evenly, if you see what I mean). Just to be sure, I managed to get hold of a good coil pack and put that on, but results the same.
Conclusion: The ECU is not firing properly on cylinders 2 and 3. To me that is the end of the story (faulty ECU). Time for the scrapyard. Ka RIP...
Result: the backfiring stops completely and cylinders 1 and 4 run OK (lumpy but evenly, if you see what I mean). Just to be sure, I managed to get hold of a good coil pack and put that on, but results the same.
Conclusion: The ECU is not firing properly on cylinders 2 and 3. To me that is the end of the story (faulty ECU). Time for the scrapyard. Ka RIP...
We have a 2007 Ford Ka (1.3) and had the misfire issue.
Having changed the coil pack, plugs, HT leads and fuel filter (Inc the eng oil - synthetic and filter) the problem continued to a lesser extent, when 12 months later it got much worse - the engine management light was coming on (dash light.) Running on three cylinders.
So again I changed the plugs with better (Bosch HR7DCX+) and still a slight misfire. I then changed the HT leads and noticed arcing marks on the installed leads (they were very cheap no brand items that came with a service pack) so replaced them with with Eurocarparts.com item number = 409595530 pro spark ignition leads. (£23.99)
The issue is now solved.
So my advice is change the HT leads first and do not buy the cheap service packs advertised on E-bay etc.
I have since watched a TV program (The garage thing in Spain with the Scottish owner.) and it stated the HT leads burning out is a common problem on the Ford Ka. Something I have also been told by a friend who is a mechanic.
Hope this helps.
Having changed the coil pack, plugs, HT leads and fuel filter (Inc the eng oil - synthetic and filter) the problem continued to a lesser extent, when 12 months later it got much worse - the engine management light was coming on (dash light.) Running on three cylinders.
So again I changed the plugs with better (Bosch HR7DCX+) and still a slight misfire. I then changed the HT leads and noticed arcing marks on the installed leads (they were very cheap no brand items that came with a service pack) so replaced them with with Eurocarparts.com item number = 409595530 pro spark ignition leads. (£23.99)
The issue is now solved.
So my advice is change the HT leads first and do not buy the cheap service packs advertised on E-bay etc.
I have since watched a TV program (The garage thing in Spain with the Scottish owner.) and it stated the HT leads burning out is a common problem on the Ford Ka. Something I have also been told by a friend who is a mechanic.
Hope this helps.
Edited by Andy9366 on Saturday 15th October 20:41
Edited by Andy9366 on Saturday 15th October 20:44
Edited by Andy9366 on Saturday 15th October 20:46
Edited by Andy9366 on Saturday 15th October 20:52
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