I'm getting a P1133 from the ECU. Has anyone diagnosed this problem? I'm running out of guesses, and I can't pass smog until I get this figured out.

My truck is a 99 4runner, v6, auto, 2wd, CA Emissions, with a 2nd gen supercharger, Supra injectors, FTC1, TRD headers & exhaust, 190 lph fuel pump, elbow mod, and 1-step colder plugs.

It runs fine, but the check engine light comes on after 5-10 minutes of driving. I think it might be caused by the ECU trying to check the front O2 sensor(which I just replaced), and is having problems getting a good signal from the FTC1.

 

all i know is the code means its running too lean.

check vacuum hoses and connections. check the install of the supercharger.

when did it start happening (after an istall of something, etc)?

 

Excellent guess... That code is:

"Air/Fuel sensor slow response (Bank 1)"


Good luck!

 

im thinking of a different code then.

 

For a list of OBDII codes, inlcuding Toyota Specific Codes, go here.

With regards to your code: Your truck is a CA emission truck. It does NOT have an standard O2 Sensor in the front position. It is an Air Fuel Ratio sensor. If you replaced it with a standard O2 sensor, then that explains the code. Did the code start before or after you replaced this piece and why did you replace it?

More info please.

G

 

Thanks for the help!

When I first installed the injectors and the FTC a few months ago, I was able to tune the fuel maps using the Long Term Fuel Trim. The first cold morning I drove to work, I got a P1133. Then the car started stuttering. I checked the LTFT and STFT, which were both saying the engine was extremely rich...they were both around -20 on the BR3. I had assumed that I had been running rich for too long, and had used up the sensor.

I replaced it with a sensor from a junk yard, which turned out to be a regular O2 sensor. I was able to tune everything, it did not run rich when cold, but the P1133 code always came on after about 5 minutes of driving, hot or cold.

A couple days ago, I had to get the truck smogged. It failed because the check engine light was coming on. So I went to the dealer and got the correct Air/Fuel Sensor. I installed it last night, and drove about 30 miles to work. On the way home last night, the engine was cold, and the P1133 came back.

This morning, the stuttering and the rich LTFT & STFT were back. I put the regular O2 sensor back in so I could get to work.

Ken

 

I called Split Second, who said that since I have a Air/Fuel Ratio Sensor, and not a regular O2 sensor, that I should not have the sensor hooked into the FTC1E. Mark said that the ESC feature is only thing using the O2 sensor, and that it would not work with the Air/Fuel Ratio Sensor. I'll test this out tonight.

 

I was going to ask you next if you had the FTC1-E and had hooked up the ESC function... As you found out, it doesn't work with the newer A/F Ratio sensors.

It sounds like it runs fine in Closed Loop, but has problems in Open Loop. Open Loop happens when you first fire up the truck when it is dead cold. It lasts about 45 seconds, or until the front Sensor heats up. For the record, Open Loop also happens during WOT, in case someone wants to make a point about that.

So, did you sort it all out? Is the truck running fine now?

Just wondering...
G

 

I disconnected the A/F wires from the FTC1E and spliced the ECU to the A/F back together, put the A/F sensor back in the bung, and everything runs great!

Thanks for the input!

 

Awesome!

Glad to hear it.

Peace!
G