take a look at your breather hose.
there might be a leak or a split.
misfire might be caused when the ecu is trying to compensate for the leak.
there might be a leak or a split.
misfire might be caused when the ecu is trying to compensate for the leak.
cupra-paul
Guest
thanks i will have to check them in the morning, i have tried vagcom on it and all it said was intermettant missfire on various cylinders. i was hoping for a more accurate answer from it. ecu light has been on but only flashed afew times then went off again.
cupra-paul
Guest
my car sounds very similar to your videoi checked hoses closely the other day, found a split in the y shaped cam cover/crank breather. i changed it, cost £29 from dealers, started it next morning and it was no better, just bought 4 coil packs from dealers £93 still the same, today i bought a coolant temp sensor to see if that works, but i doubt it will.
i have the full version of vag-com but like i said it finds fault code p0300 (random/multiple misfire on various cylinders). which is giving me nothing to specifically to look for.
is it possible for a sensor to fail and not show as a fault on vag-com?
all advice welcome as i dont know what to do next.
i have the full version of vag-com but like i said it finds fault code p0300 (random/multiple misfire on various cylinders). which is giving me nothing to specifically to look for.
is it possible for a sensor to fail and not show as a fault on vag-com?
all advice welcome as i dont know what to do next.
SimmoCupra
Guest
Search under my posts. had exactly the same thing.
You will get the response "Change this and change that" from a lot of people. I went through two sets of plugs, coil packs, and two MAFS! Even pinned out the harness section to the MAF unit.
I think what the problem is, is an intermittant signal going back to the ECU probably from the MAF wiring.
Do this:
When the car is cold, fire it up. Bonnet up. (get ready to unplug the MAF unit).
As soon as you see it missfiring - unplug the MAF . Mine went smooooth as a smooth thing as soon as I did this.
I am assuming the ECU calibration is adaptive in its learning, and does overtime learn to drive and run the engine differently once its seen a fault. You will need to clear the ECU adaptive memory and any fault codes.
I managed to cure mine (people will probably say this doesnt work too) by disconnecting the battery for 30 mins, Disconnect the ECU if you can..
Reconnect. Remember the radio code if you have one first..
And its fine for probably around 2 months, then I will notice a missfire. Again disconnect and away you go. I have had diagnostic equipment on the car when its been showing the same problem you describe with no results...
Let me know how you go.
You will get the response "Change this and change that" from a lot of people. I went through two sets of plugs, coil packs, and two MAFS! Even pinned out the harness section to the MAF unit.
I think what the problem is, is an intermittant signal going back to the ECU probably from the MAF wiring.
Do this:
When the car is cold, fire it up. Bonnet up. (get ready to unplug the MAF unit).
As soon as you see it missfiring - unplug the MAF . Mine went smooooth as a smooth thing as soon as I did this.
I am assuming the ECU calibration is adaptive in its learning, and does overtime learn to drive and run the engine differently once its seen a fault. You will need to clear the ECU adaptive memory and any fault codes.
I managed to cure mine (people will probably say this doesnt work too) by disconnecting the battery for 30 mins, Disconnect the ECU if you can..
Reconnect. Remember the radio code if you have one first..
And its fine for probably around 2 months, then I will notice a missfire. Again disconnect and away you go. I have had diagnostic equipment on the car when its been showing the same problem you describe with no results...
Let me know how you go.
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No never rev it from cold and dont give it the beans until is nice and warm. Changed 2 coilpacks but have 2 to go so will see if that sorts it as want to change them anyway as 65k on originals (might be a record lol)
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