Skip the auto shop - Our mechanics make house calls

Q: Audi A3 Quattro Misfires while idling

asked by on

When my car idles from 6 to 16 seconds it starts to misfire on all the cylinders. The fault code from what I can remember says it miss fires on 5 cylinders. I fixed the problem by revving up the engine. But if I let it idle it will miss fire again. I brought it to the repair shop and they said it might be caused from contaminated fuel. I have put new fuel in the car 4 or 5 times now, and they replaced the fuel filter. But it didn’t help. Do you have any ideas or suggestions?

A: Hello. If the misfire is only on that cylin...

Hello. If the misfire is only on that cylinder, then it may have a bad spark plug or ignition coil. The coils are a common failure on this vehicle.

If the misfire is on multiple cylinders, then the issue may be due to the timing belt being worn. I usually do a cylinder balance test to see which one is causing the issue. I also check the codes to see if the misfire is confined to one cylinder. If the coil and spark plug are fine, then a compression test will need to be done to see if there are any problems with the internal parts of the engine. If you want to have this done, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the misfiring problem and perform the appropriate adjustments/repairs.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: engine rev up and down on idle

This may be related to a dirty or failing idle air control valve. The idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at...

Q: How do I use the Fuel Used setting?

The driver information center (DIC) provides you with a lot of different information. At any moment, you can choose which information you would like the DIC to provide. To choose the Fuel Used setting, press the Menu button on the...

Q: Engine performance at low RPM's

I'm willing to bet you have one or more vacuum leaks affecting the engine idle and take-off performance. They could be associated with the brake booster or the brake booster check valve, or you may have an air leak in...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.