Engine Light On

[carlover]

My 1999 ES300 engine light is on. I had the car analyzed and codes P0125 & P1133 are present. I have replaced the O2 sensor 1 bank 1 to no avail. How do I isolate the problem before purchasing and replacing more sensors? If you can please provide pictures with location of items that may need replacing.

Thanks

[steviej]

First off, P1133 is the code for the Air/Fuel Ratio Sensor (Bank 1 Sensor1). Bank 1 is the rear bank of cylinder, the three closest to the firewall and windshield. Sensor 1 is the one up high, between the exhaust manifold and the catalytic converter. Is this the one you replaced?

Secondly, code P0125 is "Insufficient Coolant Temperature for Closed Loop Fuel Control" I would suspect a faulty coolant temperature sensor.

After the A/F sensor was replaced, did you at least have the codes reread to see if at least the P1133 code was rectified?

steviej

[97flemingLS400]

First off, P1133 is the code for the Air/Fuel Ratio Sensor (Bank 1 Sensor1). Bank 1 is the rear bank of cylinder, the three closest to the firewall and windshield. Sensor 1 is the one up high, between the exhaust manifold and the catalytic converter. Is this the one you replaced?

Secondly, code P0125 is "Insufficient Coolant Temperature for Closed Loop Fuel Control" I would suspect a faulty coolant temperature sensor.

After the A/F sensor was replaced, did you at least have the codes reread to see if at least the P1133 code was rectified?

steviej

My check engine light and No Trac light came on today all at once -- at the same time. I need to take it to Advance Auto and get them to get codes on them.

[97flemingLS400]

First off, P1133 is the code for the Air/Fuel Ratio Sensor (Bank 1 Sensor1). Bank 1 is the rear bank of cylinder, the three closest to the firewall and windshield. Sensor 1 is the one up high, between the exhaust manifold and the catalytic converter. Is this the one you replaced?

Secondly, code P0125 is "Insufficient Coolant Temperature for Closed Loop Fuel Control" I would suspect a faulty coolant temperature sensor.

After the A/F sensor was replaced, did you at least have the codes reread to see if at least the P1133 code was rectified?

steviej

My check engine light and No Trac light came on today all at once -- at the same time. I need to take it to Advance Auto and get them to get codes on them.

Mine also is a '99 ES 300 by the way.

P1133 is the code that came up when Advance Auto did a scan for me. I had just a day or two before filled up with fuel and put Gumout injector cleaner with the fuel -- don't know if that is simply coincidence, but I wonder is there is any connection...

Car is running fine -- how quickly must this issue be addressed?

[97flemingLS400]

First off, P1133 is the code for the Air/Fuel Ratio Sensor (Bank 1 Sensor1). Bank 1 is the rear bank of cylinder, the three closest to the firewall and windshield. Sensor 1 is the one up high, between the exhaust manifold and the catalytic converter. Is this the one you replaced?

Secondly, code P0125 is "Insufficient Coolant Temperature for Closed Loop Fuel Control" I would suspect a faulty coolant temperature sensor.

After the A/F sensor was replaced, did you at least have the codes reread to see if at least the P1133 code was rectified?

steviej

My check engine light and No Trac light came on today all at once -- at the same time. I need to take it to Advance Auto and get them to get codes on them.

Mine also is a '99 ES 300 by the way.

P1133 is the code that came up when Advance Auto did a scan for me. I had just a day or two before filled up with fuel and put Gumout injector cleaner with the fuel -- don't know if that is simply coincidence, but I wonder is there is any connection...

Car is running fine -- how quickly must this issue be addressed?

This is an update re. the two lights that came on. After running the car about 100 miles the two lights went off just as suddenly as they came on. Then the next time that I filled up with fuel, they came on again, only to go off again after about 100 miles of driving. Both times I filled the tank until the gas pump stopped, then squeezed in about a gallon more to top off the tank.

This is a real puzzle to me, but all the evidence (circumstantial, I admit) seems to point to the lights coming on somehow being related to filling the gas tank really full.

[steviej]

This is an update re. the two lights that came on. After running the car about 100 miles the two lights went off just as suddenly as they came on. Then the next time that I filled up with fuel, they came on again, only to go off again after about 100 miles of driving. Both times I filled the tank until the gas pump stopped, then squeezed in about a gallon more to top off the tank.

This is a real puzzle to me, but all the evidence (circumstantial, I admit) seems to point to the lights coming on somehow being related to filling the gas tank really full.

your CEL light issue in this case may be related to your gas cap and overfilling the tank. Technically you should fill up to the first stop and then not force anymore in. I wonder if the rubber seal around you cap is dry and cracked, it is 10 years old.

steviej