P1605 on Toyota
Rough idling (Toyota)
Severity: Inspect soon
On Toyota, P1605 means the idle sagged or wavered badly enough to nearly stall. The engine usually keeps running, but it can stall at a stop, so get it diagnosed soon.
It gets more serious if:
- Stop: The engine stalls or loses power while driving. Owners report P1605 with stalls at stoplights and loss of speed on the highway. Get off the road safely and have it checked or towed before driving again.
This page covers only what differs on Toyota. For what P1605 means, the ranked causes and the test order, see the P1605 guide.
What's different on Toyota
ToyotaYour car
2012–2015 · Sequoia · 3UR-FBE
Supported by vehicle dataOn the flex-fuel 3UR-FBE, a wrong learned alcohol content can set P1605 with P1604 and fuel trim codes (T-SB-0058-13).
2012–2015 · Tundra · 3UR-FBE
Supported by vehicle dataSame flex-fuel alcohol-learning bulletin as the Sequoia (T-SB-0058-13).
2014–2018 · Highlander
Supported by vehicle dataCheck the engine computer connector for water and corrosion if an aftermarket windshield with a de-icer is fitted (T-SB-0072-19).
2015–2018 · RAV4
Possible — needs testingOwners report stalls at stoplights and in traffic with P1605 stored. Owner reports only.
T-SB-0058-13Status unverified
Toyota T-SB-0058-13 (revised): 3UR-FBE MIL with P1604, P1605 and fuel trim codes
2012–2015sequoia, tundra · 3UR-FBE · issued · NHTSA 10132332
Some 2012-2015 Sequoia and Tundra trucks with the 3UR-FBE engine may set lean or rich codes, P1604 (startability) or P1605 (rough idling) after starting because the alcohol density estimate is high for the fuel actually used.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
T-SB-0072-19Status unverified
Toyota T-SB-0072-19: drivability and P1603-P1605 from ECM connector corrosion
2014–2018highlander · issued · NHTSA 10162756
Water and corrosion in the A43 engine computer connector, from poorly sealed aftermarket windshield de-icer harnesses, can cause drivability problems, low fuel pressure and codes including P1603, P1604 and P1605.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.
Sources and review
- Toyota T-SB-0058-13: 3UR-FBE MIL with P1604 Startability and P1605 Rough Idle
- ALLDATA Tech Tip: Sequoia extended cranking, DTCs P1601-P1605
- Toyota T-SB-0072-19: Highlander ECM connector corrosion, P1603/P1604/P1605
- NHTSA complaint ODI 10928436: 2015 Toyota RAV4 stalls at stops with P1605
- NHTSA complaint ODI 11205338: 2018 Toyota RAV4, dealer readout P1603 engine stall, P1605 rough idling
- TAT Scandata: P1605 (Toyota) Rough Idling
- 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