According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2008 Audi A4 has 3 documented known issues, with 2 rated critical. The most serious are 2007-2013, 2015-2016 A4 2.0T Coolant Leak at Pump or Thermostat - TSB 2061604/5 and Broken Crank Sensor Harness Behind the Bellhousing Mimics a Dead Sensor ($100-$400 repair). Across all issues with published estimates, repair costs range from $100 to $1,800. DIY maintenance guides at au7o.io.
On the 2007-2016 Audi A4, audi TSB 2061604/5 applies to A4 2.0TFSI vehicles for model years 2007-2013 and 2015-2016 when the coolant-temperature warning is on or clear coolant marks are visible under the front of the vehicle or engine compartment, the leak can be reproduced, and pressure testing localizes it to the coolant pump or thermostat housing. The bulletin excludes model year 2014 and does not support 2017-2020, a universal failure mileage or a preventive replacement schedule.
Common Symptoms
Coolant-temperature warning illuminated
Clear coolant marks under the front end or engine compartment
How to Fix
Photograph the leak with date and VIN reference and pressure-test the cooling system according to Audi workshop instructions. Replace only the component confirmed to be leaking: the coolant pump or the thermostat housing. Follow current Audi repair and parts information for exact fitment. Do not replace both components, buy a bundled kit or infer the source from a warning or puddle alone.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
Engine Coolant Thermostat
Cross-refTHRVG-0001
Fitment confirmed against the ShowMeTheParts catalog for this vehicle's year and engine.
On the 2002-2008 Audi A4, b6/B7 A4 owners who set P0322 almost always buy an engine speed sensor (G28) first, and a share of them are back on the forums a week later with the same code and the same no-start. The reason is that on this platform the failure is often the circuit rather than the pickup. The G28 lives at the bellhousing above the flywheel ring gear, and its lead runs up the back of the engine through a zone that sees exhaust heat, oil weepage and constant vibration from engine rock. Insulation hardens and chafes, a conductor breaks inside the loom, or the connector's female terminals spread and oxidise - and any of those gives the ECM the same result as a dead sensor: zero pulses, and P0322 stored as no signal. Ross-Tech's guidance for 16706/P0322 is explicitly to check the wiring to and from the sensor and the ECM before condemning the part, and at least one documented case traced the fault to a broken signal wire far from the sensor, up in the main loom near the ECU under the scuttle panel.
Owners describe an engine that cranks at normal speed and never fires, sometimes preceded by weeks of hot-restart hesitation or a stall pulling into a parking space. Both the 1.8T and the 2.0T FSI are affected, and the code often shows up alongside P0321 (implausible/erratic signal) when the circuit is intermittently making contact rather than fully open - that pairing is a strong hint that the problem is a connection, not the sensor element.
On the A4 there is also a purely mechanical version of the same complaint: a replacement sensor that is not pushed fully into its bore, or whose retaining bolt is left loose, sits at too large an air gap and reproduces the no-signal fault straight after the repair. What makes this pattern worth calling out separately is the money it wastes - the sensor is cheap, but diagnosis by parts substitution is not.
Code returns after a new crankshaft position sensor is fitted
Stalling when hot
P0321 stored alongside P0322
Zero RPM on scan tool while cranking
How to Fix
Start at the connector, not the parts counter. Raise the car, find the G28 at the bellhousing and unplug it. Inspect the pigtail along its whole visible run for chafe, heat damage and oil soaking, and look at both halves of the connector for spread pins, corrosion or green film; a terminal that has lost tension can be re-tensioned or the connector body replaced with a repair pigtail. With the sensor unplugged, measure its resistance across the signal terminals - an open reading condemns it - and then check continuity and insulation on the harness side back to the ECM connector, plus the shield and grounds. Wiggle-testing the loom while watching engine speed on a scan tool during cranking will usually expose an intermittent break; note that on documented cases the break was not near the sensor at all but up in the main loom by the ECU, so do not stop at the engine bay.
If the wiring is good and the sensor is open, fit a Bosch or genuine Audi replacement rather than a bargain unit; poor-quality sensors are a recurring theme in the threads on this code. Whichever part you fit, seat it all the way to its shoulder in the bore and tighten the retaining bolt properly - a common "new sensor didn't fix it" outcome is nothing more than a sensor that was not fully seated. If the harness is the culprit, repair it with soldered and heat-shrunk joints or a factory repair lead, and re-route the section away from the exhaust so the same chafe point does not come back.
Clear the fault, then verify with the scan tool that engine speed reads correctly while cranking and that the code does not return after several heat cycles. Parts run roughly $40-$150 for the sensor and very little for a repair pigtail; a shop will typically bill an hour of diagnosis plus an hour of labour, putting the whole job in the $150-$400 range.
On the 2002-2008 Audi A4, the multi-link front suspension used on B6/B7 A4 models is well known for premature wear of upper and lower control arm bushings/ball joints and, in many cases, outer tie-rod ends. Owners commonly report front-end clunking over bumps, looseness in steering, shimmy at highway speeds, and abnormal inner-edge tire wear. The issue is widely documented in owner forums and repair databases because multiple arms can wear at once, making the front end feel unstable even when alignment is repeatedly corrected.
Diagnosis usually involves checking each front control arm ball joint and bushing for play with the suspension loaded, along with inspecting tie rods and verifying alignment. The durable fix is replacing the worn arms as a matched kit rather than one-by-one, followed by a proper four-wheel alignment. If pinch bolts are seized, additional labor is often required, and sway bar links should be inspected at the same time.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
Suspension Control Arm and Ball Joint Assembly
Cross-refRK100092
Fitment confirmed against the ShowMeTheParts catalog for this vehicle's year and engine.
According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 2008 Audi A4 has 3 documented issues. The most frequently reported are: 2007-2013, 2015-2016 A4 2.0T Coolant Leak at Pump or Thermostat - TSB 2061604/5, Broken Crank Sensor Harness Behind the Bellhousing Mimics a Dead Sensor, B6/B7 Front Suspension Control Arm and Tie-Rod Wear Causing Clunks, Vibration, and Uneven Tire Wear. Of these, 2 are rated critical and should be addressed promptly.
Is the Audi A4 reliable?
The 2008 Audi A4 has 3 known issues compiled from NHTSA recalls, manufacturer TSBs, and owner forum reports. 2 issues are rated critical: 2007-2013, 2015-2016 A4 2.0T Coolant Leak at Pump or Thermostat - TSB 2061604/5 and Broken Crank Sensor Harness Behind the Bellhousing Mimics a Dead Sensor. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common Audi A4 problems?
Repair costs for known Audi A4 issues range from $100 to $1,800, depending on the specific problem and whether you choose DIY or professional repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What is the 2007-2016 Audi A4 2007-2013, 2015-2016 A4 2.0T Coolant Leak at Pump or Thermostat - TSB 2061604/5?
Audi TSB 2061604/5 applies to A4 2.0TFSI vehicles for model years 2007-2013 and 2015-2016 when the coolant-temperature warning is on or clear coolant marks are visible under the front of the vehicle or engine compartment, the leak can be reproduced, and pressure testing localizes… Severity: high.
What is the 2002-2008 Audi A4 Broken Crank Sensor Harness Behind the Bellhousing Mimics a Dead Sensor?
B6/B7 A4 owners who set P0322 almost always buy an engine speed sensor (G28) first, and a share of them are back on the forums a week later with the same code and the same no-start. The reason is that on this platform the failure is often the circuit rather than the pickup. The G… Repairs typically run $100-$400. Severity: high.
What is the 2002-2008 Audi A4 B6/B7 Front Suspension Control Arm and Tie-Rod Wear Causing Clunks, Vibration, and Uneven Tire Wear?
The multi-link front suspension used on B6/B7 A4 models is well known for premature wear of upper and lower control arm bushings/ball joints and, in many cases, outer tie-rod ends. Owners commonly report front-end clunking over bumps, looseness in steering, shimmy at highway spee… Repairs typically run $700-$1,800. Severity: medium.
Content on this page was compiled with AI assistance using NHTSA complaints, TSBs, owner reports, and public automotive data. While we strive for accuracy, this information may contain errors. Always verify repair procedures and specifications with your vehicle's service manual or a qualified mechanic.
