Investigations
STUCK-OPEN THROTTLE
NHTSA Preliminary Evaluation PE04023 — closed, opened 2004-03-05 and involving the AUDI AUDI.
NHTSA investigation PE04023 is a Preliminary Evaluation opened on 2004-03-05 and currently closed. The subject of record is AUDI AUDI, which places this file inside the Office of Defects Investigation queue for AUDI. Latest activity on this investigation was logged on 2004-06-30 — NHTSA updates that field whenever an Information Request goes out, a supplement is filed, or a status change is recorded in the public docket.
A Preliminary Evaluation like PE04023 is the entry point of the federal defect-investigation process. NHTSA engineers scan complaint databases, field reports, and manufacturer data to decide whether an Engineering Analysis is warranted, whether a voluntary recall is already sufficient, or whether the pattern does not rise to a defect finding.
Investigators summarized the matter as follows: "COMPLAINTS RECEIVED BY ODI AND AUDI ALLEGE THAT, IN EXTREME COLD WEATHER, THE THROTTLE MAY UNEXPECTEDLY FAIL TO RETURN TO IDLE WHEN THE ACCELERATOR PEDAL IS RELEASED, MAKING IT DIFFICULT TO STOP THE VEHICLE. IN MARCH OF..." Investigations are the early-warning layer of the federal auto-safety system, sitting upstream of formal recalls and defect orders. Whether this one closes without action or escalates into an Engineering Analysis, the full history stays in the ODI archive so researchers, litigators, and buyers can pull the paper trail at any time. Related AUDI files, listed below, give context on whether this is an isolated concern or part of a broader pattern across the brand.
Investigation Summary
COMPLAINTS RECEIVED BY ODI AND AUDI ALLEGE THAT, IN EXTREME COLD WEATHER, THE THROTTLE MAY UNEXPECTEDLY FAIL TO RETURN TO IDLE WHEN THE ACCELERATOR PEDAL IS RELEASED, MAKING IT DIFFICULT TO STOP THE VEHICLE. IN MARCH OF 2004, AUDI PERFORMED A SERIES OF TESTS TO INVESTIGATE THE POSSIBLE CAUSES OF THROTTLE ICING. AUDI CONCLUDED THAT UNDER CERTAIN DRIVING CONDITIONS - ONLY SHORT DISTANCE TRIPS OVER SEVERAL WEEKS WHERE COOLANT TEMPERATURE REMAINS BELOW 70°C (158¿F) - WATER MAY ACCUMULATE IN THE MOTOR OIL. WATER THAT HAS ACCUMULATED IN THE MOTOR OIL WILL EVAPORATE AFTER THE ENGINE OIL TEMPERATURE EXCEEDS 70°C (158¿F) AND COULD, WITHIN 15 TO 20 MINUTES OF DRIVING AT A CONSTANT SPEED WITH AN OUTSIDE TEMPERATURE BELOW -20°C (-4OF), CAUSE ICE TO FORM IN THE THROTTLE BODY. ACCORDING TO AUDI, THIS CONDITION OCCURS AT RELATIVELY LOW THROTTLE SETTINGS AND RESULTS IN THROTTLE STICKING AT POSITIONS THAT CAN BE CONTROLLED BY BRAKING. DURING TYPICAL VEHICLE USAGE (MIXTURE OF SHORT AND LONG DISTANCE DRIVING) THIS PHENOMENON IS NOT EXPECTED TO OCCUR. THIS INVESTIGATION HAS BEEN UPGRADED TO AN ENGINEERING ANALYSIS.
About This Investigation Type
A Preliminary Evaluation (PE) is the first phase of NHTSA's investigation process. It is opened when the agency identifies a potential safety defect pattern, usually triggered by consumer complaints, manufacturer reports, or field monitoring. During a PE, NHTSA gathers information to determine whether a formal engineering analysis is warranted.
Other AUDI Investigations
Engine Stall - Turbo Failure
Engine Stall - Turbo Failure
STUCK-OPEN THROTTLE
DRIVERS SIDE DASH FIRE
DRIVERS SIDE DASHBOARD FIRE
Data from NHTSA Office of Defects Investigation. Cross-references: NHTSA recall campaign API and NHTSA FARS where fatality records overlap. PlainCars does not rate or recommend vehicles. Learn more.
Read our methodology — how this data is sourced, computed, and verified.