Torque dip around 4,000 rpm
Added · Updated
What causes "Torque dip around 4,000 rpm" on the Toyota 86 / Subaru BRZ / Scion FR-S (ZN6/ZC6, 2013-2020), and how is it fixed?
A characteristic of the stock FA20 intake, exhaust and tune, not a fault. Fix: An aftermarket header with a matching tune mostly fills the dip.
Symptoms
A noticeable flat spot in pull in the mid-range, around 4,000 rpm.
Cause
A characteristic of the stock FA20 intake, exhaust and tune, not a fault.
Fix (summary)
An aftermarket header with a matching tune mostly fills the dip. One retailer claims about 14 lb-ft in the dip from a header and about 20 whp from a tune, with more on E85. These figures come from a parts seller. Check emissions rules where you live before changing the header.
Related build entries
Other ZN6/ZC6 problems
- Valve spring recall (2013 BRZ and FR-S)
- Low-pressure fuel pump recall (2018-19)
- Key can come out when not in Park (FR-S and 86 automatics)
- Rough idle or stalling on early cars (ECU software)
- Oil seepage from the cam plate, cam carriers or timing cover
- High-pitched chirp or cricket noise from the engine
More for this car
- All Toyota 86 / Subaru BRZ / Scion FR-S (ZN6/ZC6, 2013-2020) fitment answers · ZN6/ZC6 common problems
- Newsletter archive: past issues with every new and corrected entry
Sources
- Fix The Torque Dip on Scion FR-S/Subaru BRZ/Toyota 86 — ModBargains (parts retailer blog) (vendor article; read 2026-10-26; full page read)
Summaries are in our own words. Not repair instructions; consult the factory service manual.
Report a correction — spotted an error or have a better source? Email hello@chassisdex.com.