I have searched the forums but can't find exactly this problem.
2010 Camry 4 cyl 281,000 miles
Intermittent problem of rough idle for the first few minutes when the car is started.
No problem starting. Immediately the car is either clearly running fine or idling rough. If it is idling rough it is almost impossible to drive. The rough idle produces higher RPMs (1200 vs 800, see data below). If you press the gas pedal it sounds about normal at 2000+ RPMs but when you let off it goes back to rough idling. If you try to drive it is very rough. If you just let it idle it fixes itself (starts idling fine) after 3 to 5 minutes. It is almost like clockwork. The change from idling rough to normal idling is immediate. It is like something electronic is switched. It seems to not matter what you do (restart, drive, press gas pedal, etc.), the rough idle remains until the time passes. You can hear the engine clearly switch from rough to smooth and the RPMs drop. The time for the fix is about the same regardless of the temperature. Whether it starts with the problem also does not seem affected by temperature.
The car will start and idle normally as long as it stays warm. Usually the problem happens again only after the car has completely cooled (overnight). But it does not happen every time the car is started even when it is cold.
I would think it is either an electronic problem or a vacuum problem that fixes itself after it warms up. It is almost like it is learning the idle information again like when you disconnect the battery cable. Maybe it is randomly losing the idle information and takes 3 to 5 minutes to relearn it before running fine.
Only rarely does it produce a check engine light which is usually just a cylinder misfire.
Other notes:
Here is what I have done to try and fix the problem and it has had no affect:
Live Data from 7/10/2024:
Thanks,
-Roy
2010 Camry 4 cyl 281,000 miles
Intermittent problem of rough idle for the first few minutes when the car is started.
No problem starting. Immediately the car is either clearly running fine or idling rough. If it is idling rough it is almost impossible to drive. The rough idle produces higher RPMs (1200 vs 800, see data below). If you press the gas pedal it sounds about normal at 2000+ RPMs but when you let off it goes back to rough idling. If you try to drive it is very rough. If you just let it idle it fixes itself (starts idling fine) after 3 to 5 minutes. It is almost like clockwork. The change from idling rough to normal idling is immediate. It is like something electronic is switched. It seems to not matter what you do (restart, drive, press gas pedal, etc.), the rough idle remains until the time passes. You can hear the engine clearly switch from rough to smooth and the RPMs drop. The time for the fix is about the same regardless of the temperature. Whether it starts with the problem also does not seem affected by temperature.
The car will start and idle normally as long as it stays warm. Usually the problem happens again only after the car has completely cooled (overnight). But it does not happen every time the car is started even when it is cold.
I would think it is either an electronic problem or a vacuum problem that fixes itself after it warms up. It is almost like it is learning the idle information again like when you disconnect the battery cable. Maybe it is randomly losing the idle information and takes 3 to 5 minutes to relearn it before running fine.
Only rarely does it produce a check engine light which is usually just a cylinder misfire.
Other notes:
Here is what I have done to try and fix the problem and it has had no affect:
- Cleaned throttle body and related parts
- Changed spark plugs
- Changed air filter
Live Data from 7/10/2024:
| Category | 1st - rough idle 9:13 am | 2nd - 2nd rough idle 9:14 am | 3rd - 1st normal idle 9:19 am | 4th - 2nd normal idle after driving 9:32 am | 5th - 3nd normal idle after driving/shut off/restart/drive (also cleared code) 9:48 am |
| DTC_CNT | 1 | 1 | 1 | 1 | 0 |
| FUELSYS1 | CL | CL | CL | CL | CL |
| FUELSYS2 | N/A | N/A | N/A | N/A | N/A |
| LOAD_PCT (%) | 49.8 | 43.9 | 34.1 | 30.2 | 31.0 |
| ECT (°F) | 88 | 118 | 154 | 190 | 198 |
| SHRTFT1 (%) | 3.9 | -5.5 | -6.3 | 0.0 | 2.3 |
| LONGFT1 (%) | -4.7 | -5.5 | -3.1 | -8.6 | -7.0 |
| RPM (/min) | 1524 | 1124 | 801 | 662 | 659 |
| VSS (mph) | 0 | 0 | 0 | 0 | 0 |
| SPARKADV (°) | -2 | 8 | 10 | 9 | 10 |
| IAT (°F) | 84 | 86 | 97 | 113 | 124 |
| MAF (lb/min) | 1.262 | 0.784 | 0.427 | 0.280 | 0.295 |
| TP (%) | 20.4 | 18.0 | 16.9 | 16.1 | 16.1 |
| 02S | B1S12- -B2S- - - - | B1S12- -B2S- - - - | B1S12- -B2S- - - - | B1S12- -B2S- - - - | B1S12- -B2S- - - - |
| O2B1S2 (V) | 0.000 | 0.000 | 0.370 | 0.640 | 0.640 |
| ODB | OBD2 | OBD2 | OBD2 | OBD2 | OBD2 |
| RUNTM (sec) | 40 | 114 | 387 | 1148 | 487 |
| MIL_DIST (mile) | 0 | 0 | 0 | 2 | 0 |
| EQ_RATB1S1 | 0.989 | 0.982 | 0.981 | 0.992 | 0.996 |
| O2B1SW(\ | 3.254 | 3.191 | 3.196 | 3.269 | 3.283 |
| EVAP_PCT (%) | 0.0 | 0.0 | 0.0 | 28.6 | 16.1 |
| WARM_UPS | 134 | 134 | 135 | 135 | 0 |
| CLR_DIST (mile) | 1038 | 1038 | 1038 | 1040 | 1 |
| BARO (inHg) | 28.9 | 28.9 | 28.9 | 28.6 | 28.9 |
| EQ_RAT11 | 0.983 | 0.979 | 0.991 | 0.998 | 1.000 |
| O2S11 (mA) | -0.051 | -0.055 | -0.023 | -0.000 | 0.000 |
| CATEMP11(°F) | 802.04 | 910.40 | 857.48 | 869.36 | 843.80 |
| CATEMP12 (°F) | 133.88 | 233.96 | 413.06 | 568.76 | 478.58 |
| VPWR (V) | 14.062 | 13.984 | 13.808 | 13.632 | 13.417 |
| LOAD_ABS (%) | 27.6 | 25.3 | 18.7 | 14.7 | 15.1 |
| EQ_RAT | 0.999 | 0.999 | 0.999 | 0.999 | 0.999 |
| TP_R (%) | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 |
| AAT (°F) | 79 | 79 | 81 | 79 | 81 |
| TP_B (%) | 51.4 | 51.8 | 48.6 | 47.8 | 47.8 |
| APP_D (%) | 15.7 | 15.7 | 15.7 | 15.7 | 15.7 |
| APP_E (%) | 31.8 | 31.8 | 31.8 | 31.8 | 31.8 |
| TAC_PCT (%) | 16.0 | 17.3 | 16.5 | 16.1 | 13.1 |
| MIL_TIME | 0h:00m | 0h:01m | 0h:06m | 0h:18m | 0h:00m |
| CLR_TIME | 45h:05m | 45h:07m | 45h:11m | 45h:24m | 0h:08m |
-Roy
