Investigations

Uncontrolled Engine Speed

NHTSA Preliminary Evaluation PE99032 - closed, opened 1999-05-05.

PE99032 Preliminary Evaluation Closed

NHTSA investigation PE99032 is a Preliminary Evaluation opened on 1999-05-05 and currently closed. The subject is tracked inside the Office of Defects Investigation queue. Latest activity on this investigation was logged on 1999-06-23 - 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 PE99032 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: "On April 21, 1999, a local school bus fleet administrator contacted ODI alleging that one of their buses was involved in an engine run-away incident. After inspecting the bus and finding the governor link separated from..." 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.

Status
Closed
Type
Preliminary Evaluation
Opened
1999-05-05
Latest Activity
1999-06-23

Investigation Summary

On April 21, 1999, a local school bus fleet administrator contacted ODI alleging that one of their buses was involved in an engine run-away incident. After inspecting the bus and finding the governor link separated from the track bar due to a retaining rivet failure, ODI interviewed the driver. She claimed she was able to stop the bus after shifting to neutral but still had no control over engine speed which remained quite high. In fact, her loss of engine control was complete...she could not even shut it down. Ultimately it quit due to overheating. We found a relevant Caterpillar "Technical Information Bulletin" dated April 22, 1998 concerning "Loose Rivet in Rack Control Assembly." The rivet involved in the school bus incident and Caterpillar's bulletin are one and the same. However, the bulletin mentions nothing about the potential for engine run-away due to a rivet failure. According to the company, "the apparent cause for the rivet failure was compromised quality control of the peening process during manufacture of the control assembly. Evaluation of failure data demonstrates the quality control problem began in April 1996. Caterpillar implemented a new peening process on March 25, 1998 and no rivet failures have occurred since. This investigation was closed on June 23, 1999 with Caterpillar's safety recall.

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.

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. about how PlainCars sources NHTSA data.