Tsi300 misfire

[ziggy_jacob]

Hey all finding a misfire with my tsi300
P0300 P0301 and P0303
Misfires under idle goes away around 2-3k rpm as a starting point I threw a set of plugs at it nothing still misfiring have moved coilpacks around to find that the misfires haven't moved
Replaced pcv ,next looking at removing intake manifold to inspect for carbon buildup on valves and getting injectors tested anyone offer any advice that has been down this rabbit hole new to the obdeleven

[Sharkie]

What is the milage on it ziggy?

[Lucas_R]

Could well be carbon buildup causing those misfires if the car has 100,000+km's on it. You can do a bit of a DIY carbon clean using a spray foam product to see if it improves, but this will only be a temporary fix and you will need to get the intake valves cleaned properly. There is a mechanic in Maitland (Diamond Mechanical) that does a lot of VW and other Euro's.

There is a temperature sensor on the intake manifold that you can remove easily and then spray the foam cleaner in there to clean some of the gunk off the intake valves.

LIQUI MOLY Petrol Engine Intake Decarb - 366g | Supercheap Auto

[ziggy_jacob]

Just went 110k

[ziggy_jacob]

Cheers for that might try that to see any improvement

[ziggy_jacob]

Oh and it happened all of a sudden that's what makes me suss I need to a compression check
From my understanding it shouldn't be a vacuum leak because it's not all cylinders missing

[Lucas_R]

Well you have done the main culprits already (PCV, coil packs and spark plugs).

Try a can of that intake cleaner and throw a bottle of injector cleaner in your fuel tank for good measure at the same time. If you get an improvement then you know what the issue is.

Worse case scenario is timing is out from the timing chain skipping. Lets hope its not that. Are you getting any other error codes other than the misfire codes?

[ziggy_jacob]

Well you have done the main culprits already (PCV, coil packs and spark plugs).

Try a can of that intake cleaner and throw a bottle of injector cleaner in your fuel tank for good measure at the same time. If you get an improvement then you know what the issue is.

Worse case scenario is timing is out from the timing chain skipping. Lets hope its not that. Are you getting any other error codes other than the misfire codes?

No other codes that's what annoys me

[Lucas_R]

No other codes that's what annoys me

If no other codes then it's a good chance its just carbon buildup causing your issues.

[ziggy_jacob]

Thanks legends so done both treatments has reduced misfires
Still getting these codes
So assuming it's manifold off time
Trouble codes:
P050100 - Vehicle Speed Sensor "A" Range/Performance
static
P030300 - Cyl.3 Misfire Detected
static
P130A00 - Hide cylinder
static
P030000 - Random/Multiple Cylinder Misfire Detected
static