Ford Mustang 1999–2000 — technical service bulletin
Bulletin 13987 · NHTSA communication 620289 · issued Mar 1, 2001
Technical service bulletin
communication type
Engine and Engine Cooling
component
1999–2000
model years
2
vehicle entries
Official summary
Some vehicles equipped with 3.8l engines may exhibit engine spark knock on heavy acceleration with 87 octane fuel. Hot weather and lower octaine fuel can contribute to the cause of a slight knock on heavy acceleration. Though no damage to the engine will occur, some customers report that the sound is not desirable. *tt
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.