My engine light has been coming on, so I checked the code today and it gave me a 25 - Air-fuel ratio lean malfunction. Any ideas what would cause this? I'm guessing maybe a dirty fuel filter or clogged injectors?

Also, when i'm in the "diagnostic" mode. The OD light keeps blinking and doesn't stop, does that mean anything?

 

od should blink when in diag mode - it happens to me too. corect me if am wrong guys

Code 25 i guess is the O2 sensor (main one)

 

I assume a bad o2 sensor could very well trigger a 25-Air-fuel ratio lean malfunction. But if a o2 sensor was bad would it not trigger a 21 or 28 as well?

 

25 and 26 are for the O2 sensors

lOBD1 Codes
1 Normal Condition.
2 Air Flow Meter signal.
3 Ignition signal.
4 Engine Coolant Temperature Sensor signal.
5 Oxygen Sensor.
6 RPM signal (Crank Angle Pulse).
7 Throttle Position Sensor signal.
8 Intake Air Temperature Sensor signal.
9 Vehicle Speed Sensor signal.
10 Starter signal.
11 Switch signal.
11 ECU/ECM.
12 Knock Control Sensor signal.
12 RPM signal.
13 Knock Control CPU (ECM).
13 RPM signal.
14 Turbocharger Pressure.
14 Ignition signal.
21 Oxygen Sensor.
22 Engine Coolant Temperature Sensor signal.
23 Intake Air Temperature Sensor signal.
24 Intake Air Temperature Sensor signal.
25 Air-Fuel Ratio Lean.
26 Air-Fuel Ratio Rich.
27 Sub Oxygen Sensor signal.
28 No. 2 Oxygen Sensor signal.
31 Air Flow Meter signal (Vacuum Sensor signal).
32 Air Flow Meter signal.
34 Turbocharger Pressure signal.
35 Turbocharger Pressure Sensor signal.
35 HAC Sensor signal.
41 Throttle Position Sensor signal.
42 Vehicle Speed Sensor signal.
43 Starter signal.
51 Switch signal.
52 Knock Sensor signal.
53 Knock Sensor signal.
54 Inter-cooler ECM signal.
71 EGR System.
72 Fuel Cut Solenoid signal.
78 Fuel Pump Control signal.
81 TCM Communication.
83 TCM Communication.
84 TCM Communication.
85 TCM Communicatio



however looking at this list, u may be right - it could be the secondary O2 sensors for 21 and 28?? the ones after the cats

not sure - I have an EGR Code 71 after i seafoamed the car

 

How much different is the OBD 2 diagnostic code from the OBD 1 list

 

A lot different, completely different. OBD2 fault codes will start with a letter P, for instance P0420 and so on..

 

Ordered 2 new Denso 02 Sensors (324-4211 denso #)
And 2 new coils (90919-02197 oem ) to deal with this same issue on my 94 LS.

 

my sc300 was throwing the same code and i just replace the two front sensors. I couldn't afford OEM o2 sensors for my 95 sc300 so i was able to get it on ebay, it actually came with the flange so it was a direct fit for i think like 12 bucks a piece. The bad part is you have to cut the old sensor to keep the connector and splice it with the new sensor.

 

why does the trac control light come on with code 25 and is this the driver or passenger side?