P1604 on Subaru
Startability malfunction (Toyota and Subaru)
Severity: Inspect soon
On Toyota and Subaru, P1604 means the engine was slow to start or nearly stalled right after starting. The car usually still runs, but the cause (often a weak battery) can leave you unable to start it. Get it checked soon.
It gets more serious if:
- Stop: The engine stalls or loses power while driving. Subaru owners report P1604 stored with a shorted ignition coil, a blown fuse and a stall at road speed. Get off the road safely and have it checked or towed before driving again.
This page covers only what differs on Subaru. For what P1604 means, the ranked causes and the test order, see the P1604 guide.
What's different on Subaru
SubaruYour car
2019–2020 · Ascent
Supported by vehicle dataSubaru has an ECM update for extended cranking and P1604 stored without the check engine light (11-192-19).
2019–2020 · Crosstrek
Possible — needs testingOwners report P1604 stored with a shorted ignition coil, a blown fuse and a stall. Have the coils and ignition fuse checked.
11-192-19Status unverified
Subaru 11-192-19: ECM reprogramming for extended cranking and P1604
2019–2020ascent · issued · NHTSA 10166949
New ECM files address extended cranking (hard starting) and P1604 stored without the check engine light.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
Sources and review
- Subaru 11-192-19: ECM reprogramming for extended cranking and P1604
- NHTSA complaint ODI 11627701: 2019 Subaru Crosstrek, P1604 with shorted cylinder 4 coil and blown fuse
- NHTSA complaint ODI 11735976: 2020 Subaru Crosstrek, P1604 with melted cylinder 3 coil, blown fuse and stall
- Foreign Service, July 2013: Toyota P1604 startability code
- Toyota T-SB-0166-19 Rev1: 3UR-FBE hard start, MIL with P1604 and fuel trim DTCs
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error