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Luke L. of Tinley Park, IL
Common Audi Problems
Check Engine Light on? ABS light on? Engine running rough? Here you will find some answers to the most frequently diagnosed Audi problems brought into our Audi repair shops. We do not recommend you assume that the answer here directly relates to your car. Accurate diagnosis of a problem typically saves you money. And, you should know that often third parties will misdiagnose a car for what appears to be similar problems or related diagnostic codes.
Oil Leaks and or Burning Oil Smell
Audi engines commonly leak from the valve covers or tensioner gasket seals. Of course, leaking oil can be a fire hazard – the oil hitting the exhaust and burning while you drive is the smell, so it’s best to address the problem as quickly as possible. Leaking oil can also be a risk to the engine electronics. Oil permeates through the wiring and can attack electrical connections or damage control modules. This can often become increasingly expensive the longer it is left alone. With leaking oil, the longer the problem goes the less oil you have in your engine – so this could be catastrophic if not addressed quickly.
Clunking or Clicking Sound When Making Sharp Turns
This is often the result of ignoring a previous repair required on an axle CV Boot. The most common cause of this noise on an Audi is the drying out of an axle joint. Once the CV Boot has been torn, the grease is thrown out and the joint dries out and begins to wear quickly. The Audi dealer usually replaces the whole axle assembly at an extensive price. We have a solution that rebuilds the axle and lowers the cost significantly. If your CV boots are torn, then you are driving on borrowed time before this repair is necessary. Replacing CV boots is considerably less expensive than having to replace or re-build the axle assembly.
Exhaust Leak – Sounds Throaty When Accelerating
Many Audi models have a flexible joint in the exhaust between the down-pipe and the catalytic converters. This joint is prone to weathering and often begins to leak. While the deeper exhaust note can sound cool for a while, the results can be very expensive. The leaking exhaust can cause o2 sensor codes, cat efficiency problems and check engine lights accompanied by rough running. Unfortunately, the flex pipe is generally part of the catalytic converter assembly and therefore extremely expensive to replace. However, we have a solution that just replaces the flexible joint and is considerably cheaper.
"I will definitely be taking all my cars here for all maintenance work."
Jimmy L. of Chicago, IL
Check Engine Light – Runs Rough
Rough running and a check engine light is commonly the result of misfires. Misfires can be isolated to a single cylinder or seen randomly across multiple cylinders. Random multiple misfires have many possible causes. The most common cause of misfires on a single cylinder is the ignition coil. Audi has experienced multiple issues with their ignition coils and in fact has initiated a number of recalls to replace them for free. We always check for you to see if your vehicle is subject to an open coil recall before we proceed.
Check Engine Light – Runs Great
If a check engine light stays on after a number of drive cycles and the engine runs normally the source of the problem is commonly an emissions related issue. Commonly on Audi vehicles this is a leak in the emissions gas recycling system, although typically, there are a number of common reasons that could set this situation. The worst case is a catalytic converter inefficiency problem where the exhaust gases are not being efficiently cleaned by the cat. In most cases, catalytic converters are covered under warranty for 8 years or 80K miles.
Turn Signals Stay On or Won’t Work at All
This is very common with older Audis. The common cause of this symptom is often the hazard switch. The indicators are wired through the hazard switch and failure of it causes the indicators to malfunction or stay on. This can also be the result of a faulty switch in the steering column, but this is the less likely of the 2 causes.
Coolant Leaks or Low Coolant Light On
Audis commonly have issues with a low coolant light coming on or a visible coolant leak under the car. There are a number of different reasons why this happens, however, the most common is a crack in the coolant reservoir. Often the leak is not visible until the car has warmed enough to open the crack as the coolant expands to the crack level. The leaking coolant will often reach an exhaust component first and evaporate – this makes the leak difficult to detect. Replacing the coolant reservoir is a relatively inexpensive job – certainly if compared to the cost of damage resulting from over-heating.
“I’m always impressed with the team at Rennology! That’s why I keep coming back!”
John P. of Orland Park, IL
Rattle/Knocking Noise from Engine at Cold Start
You may experience a rattle or knocking noise from the engine during a cold startup. This is caused by the camshaft chain tensioner(s) or camshaft adjuster(s) and usually lasts for 1-2 seconds after engine start. The camshaft adjustment is hydraulically actuated and controlled by the engine oil pressure. If the engine has been turned off for a longer period of time or parked outside on a winter day in Chicago, the oil pressure drops down and the oil partially flows back into the oil sump. To ensure an efficient camshaft adjustment right after an engine cold start, the oil pressure inside the camshaft adjusters must be built up as fast as possible. During this time, a rattle or knocking noise may be noticeable. This noise is normal at cold engine start and will last until the oil pressure is fully built up, which takes about 1-2 seconds. In the event the noise continues significantly longer, we recommend a more thorough diagnosis.
Unpleasant Odor from Heating and Ventilation System
This is a musty odor that emanates from the heating and ventilation system. Usually, this odor will occur if the car has sat for a few hours. Of course, there are a number of different sources for odors, but commonly mold growing in the ac ducting system is the usual source. The mold spores are present in the air and gather with moister extraction in the ac process. Left for a while in the warm summer climate they grow rapidly. We can provide a cleaning system that eliminates the mold build up and removes the odor. However, this is a service that usually needs to be applied once a season as the problem cannot be completely eliminated.
Blowing Smoke – Turbo Cars
When turbo cars start to blow smoke consistently, an urgent diagnosis is necessary. The smoke is caused by oil in the combustion process. There are a number of simple reasons why oil could be entering the combustion cycle, however the worst circumstance is a worn or failed turbo. Oil passes by the turbo and heads down the exhaust – hence the smoke. The oil has a destructive effect on the catalytic converters if not dealt with as quickly as possible. Adding catalytic converters to a turbo job increases the cost significantly. The simple way to tell if this problem exists or is going to exist soon is to remove the intercooler hose. There should be some residual oil present, however, if oil runs out of the hose in any significant quantity, then you have a larger issue that should be addressed ASAP.
Trunk Won’t Close Automatically, MMI Opens and Closes
One of the most common causes of electrical misbehavior in Audi vehicles is a shortage of good battery voltage. This comes in two versions – first a check of the battery is essential – more than 5 years old and you likely are due for a change. Secondly, the voltage distribution module is prone to failure in many Audi vehicles. The module assists in the smooth delivery of steady voltage to electrical components. When it fails or battery power is lower than expected, these devices can either fail to work or exhibit strange behavior.
Visit Our Audi Repair Shops
Having similar Audi problems? Come visit our North Aurora or Mokena location if you are experiencing any of these Audi related issues. Rennology Motor Sport offers repair, factory scheduled maintenance, and performance tuning for Audi vehicles.