Hi ! I hope someone can shed some lights on my misfires problem.
Audi A2 1.4 petrol, AUA engine, 275.000 km
So last week I was driving on the highway, the car is completely ok (but heavy with luggages), when suddenly a heavy rain drops. Within seconds, the car stutters, loss of power, MIL blinks... I manage to get to the emergency stop line before the engine shuts off.
I try to turn the engine on again, but still no power.
After a few minutes, the rain lightens a bit. I finally manage to get the engine started, and while there was very little power, I managed to exit the highway, and reach a proper parking space. The time to reach my computer and VCDS cable, rain has stopped.
So, I do a diag, and find codes P0300, P0302 and P0304 : misfires on cylinders 2 and 4, which explains the loss of power.
I clean the codes, start the engine, it run smooth. So I go to finish my travel. But after a few meters, loss of power again and blinking MIL. However, the road is mostly flat, I was near the end, and I reach home.
Luckily I was just about ready to do the service, so I have new spark plugs, new air, oil and fuel filters - I changed everything. Still misfire on 2 and 4.
I swapped the injectors - no change.
Cleaned the throttle body and EGR while I was at it, adaptation (I'm getting used to this part), no change.
I did a compression test, all cylinders seem alright : pressure between 11.4 and 12 bars.
I checked for sparks by using a spark plug at the end of the wire with contact to the body of the engine, and seen some sparks.
I believe that if there was a problem on the fuel system before injectors, or air intake, the misfire would randomly occur on every cylinders.
So I think it might be the coil or control module, but how to check for sure ? I thought about crossing the wires between the coil and spark plugs to check if I managed to make the misfire switch cylinder, but as the spark is timed for each cylinder, that would not work, right ? So how can I check the coil ?
Or maybe someone has an idea of something else that could cause this, and how to check it ?
Audi A2 1.4 petrol, AUA engine, 275.000 km
So last week I was driving on the highway, the car is completely ok (but heavy with luggages), when suddenly a heavy rain drops. Within seconds, the car stutters, loss of power, MIL blinks... I manage to get to the emergency stop line before the engine shuts off.
I try to turn the engine on again, but still no power.
After a few minutes, the rain lightens a bit. I finally manage to get the engine started, and while there was very little power, I managed to exit the highway, and reach a proper parking space. The time to reach my computer and VCDS cable, rain has stopped.
So, I do a diag, and find codes P0300, P0302 and P0304 : misfires on cylinders 2 and 4, which explains the loss of power.
I clean the codes, start the engine, it run smooth. So I go to finish my travel. But after a few meters, loss of power again and blinking MIL. However, the road is mostly flat, I was near the end, and I reach home.
Luckily I was just about ready to do the service, so I have new spark plugs, new air, oil and fuel filters - I changed everything. Still misfire on 2 and 4.
I swapped the injectors - no change.
Cleaned the throttle body and EGR while I was at it, adaptation (I'm getting used to this part), no change.
I did a compression test, all cylinders seem alright : pressure between 11.4 and 12 bars.
I checked for sparks by using a spark plug at the end of the wire with contact to the body of the engine, and seen some sparks.
I believe that if there was a problem on the fuel system before injectors, or air intake, the misfire would randomly occur on every cylinders.
So I think it might be the coil or control module, but how to check for sure ? I thought about crossing the wires between the coil and spark plugs to check if I managed to make the misfire switch cylinder, but as the spark is timed for each cylinder, that would not work, right ? So how can I check the coil ?
Or maybe someone has an idea of something else that could cause this, and how to check it ?