P1117 - can't clear code

[blue62]

Originally Posted by Zzorro

2 of 4 O2 sensors delivered. Waiting for the other 2 to arrive.

CEL came on again, so I thought I would read the codes and post up.

P1128 - Oxygen sensing range 2 Cylinder (1-3)

P1130 - Oxygen sensing range 2 Cylinder (4-6)

P1117 - Heating power 02S behind cat c. bank 1

P0140 - O2 sensor behind cat conv. Cylinder (4-6)

It will be interesting to see what happens once you change out the O2 sensors.
Looks like your not getting the SAI codes anymore?

[Zzorro]

Blue62, I ran the tests. When the SAI runs, the voltage drops way low. So the SAI is basically working properly (according to that test anyways). I could not feel air from the tailpipe after activating the SAI with the engine off.

What is interesting is the behavior of the O2 sensors as the car is warming up. The post cat voltages hover around 1v. But go up and down up to .99 and 1.06 (blue and red). The pre-cat O2 sensors bounce up and down but not that crisply. Seem like they are getting a bit "lazy" (green and yellow).

Anyways, second set of O2 sensors should be here this week. Then I'll swap them all and see what happens.

[blue62]

Originally Posted by Zzorro

Blue62, I ran the tests. When the SAI runs, the voltage drops way low. So the SAI is basically working properly (according to that test anyways). I could not feel air from the tailpipe after activating the SAI with the engine off.

What is interesting is the behavior of the O2 sensors as the car is warming up. The post cat voltages hover around 1v. But go up and down up to .99 and 1.06 (blue and red). The pre-cat O2 sensors bounce up and down but not that crisply. Seem like they are getting a bit "lazy" (green and yellow).

Anyways, second set of O2 sensors should be here this week. Then I'll swap them all and see what happens.

That test of the SAI that I described to you is exactly what the ECU does to test the SAI. The test I described is just a way to force it manually
So if it drove your pre cat O2 sensor voltages low then it seems your SAI is working properly.

If your not fully warmed up and watching your O2 sensors you could still be on a cold start fuel map so it may be a little rich. Also the Cats may not be fully lit off and hot enough to function optimally. So post cat O2 sensor readings could show rich (high voltage).

What RPM are you at when you take the screen shots of the O2 sensor graphs??
I am guessing idle.
Try getting fully warmed up. Then bringing the RPM up to 2000-2500 RPM and look at the O2 sensor reading and see if there is much difference.

Your O2 sensor graphs don't look quite right to me. And it's really hard to tell much by just a screen shot. but your changing them out anyway so no big deal

How is it running??

[Zzorro]

Correct: screen shot is from idle, just after start-up and after SAI pump stopped running. Car got to warm temperature while idling and the readings were much the same. Car seems to run just fine.

[blue62]

Originally Posted by Zzorro

Correct: screen shot is from idle, just after start-up and after SAI pump stopped running. Car got to warm temperature while idling and the readings were much the same. Car seems to run just fine.

Once you get the O2 sensors changed out graph the readings again.
But take it for a drive first so your sure the Cats are hot.
Graph them with the RPM's held around 2000-2500.
Your post cat graph lines should look much like the screen shots you posted.
but in the .450v range.

The 1.00v-1.06v in your screen shots seems out of range to me.
But they were tested at idle just after cold start.
But your changing them out so not important at this point.

[blue62]

Actually I believe I was wrong about the post cat O2 sensor voltage that I posted previously.

If the cat is working properly then it is using up all the oxygen in the catalytic process.
Therefore the post O2sensor should show a relatively flat high voltage reading.
This is fully warmed up and RPM held steady around 2000 RPM.

[Zzorro]

Started the O2 sensor swap.

They are seized in there pretty good. I'm soaking them in PB Blaster overnight. I will tackle again tomorrow.

Relatively easy so far though. All 4 connections are easy enough to reach and the red "plunger" on the connections came loose with a small screw driver a little leverage.