[davethib]

Thanks everyone for the suggestions. It seems like it may indeed be running rich since I can smell some unburned gas in the exhaust. I have questioned the O2 sensor since the exhaust system was replaced fully about 4 years ago the the tail pipe and muffler only lasted 3 years so I question the quality of the parts that were put in at the time.
I did replace the fuel infectors which improved how well it runs but did not fix the stalling problem. I need to get the probes so I can hook up my oscilloscope to view the infector timing to be certain they are not being told to be on longer then they should. Most everything else seems fine.
I really don’t want to take it to a shop where they are going to make quick assumptions and throw parts at it then charge me $1000 and it probably still will not be fixed.
Dave T

[davethib]

Hello,

I will try again to upload the first two images. The last two seem to work.
From a cold start:

Shortly after a cold start:

So in looking at these. I see that the O2 voltage starts really high before I start the engine, but I would think that is normal. Then the engine starts and it goes down to zero and rather quickly it comes up to around 820 mV and pretty much stays that way. It comes down slightly.
But then after the roughly 45 minute trip it is still up around 750mV.
So my question is if this is normal?
I guess I need to watch some of the other videos regarding the O2 sensor readings.

Thanks,

Dave T

[davethib]

Thanks Importech,

This is my daughter’s car and she is returning from her first year of college tonight so I drive the car to work today and captured some screenshots to give some good data rather than from my memory. 🙂

This first one is where I turned on the key, waited a few seconds then started the car. You can see the O2 sensor graph. The gauge to the right of the graph has number display in the middle of it. That is set to intake air temperature.

This next screenshot is right after the cold start where you see the O2 sensor come up. This is right after the first screenshot.

I took some more when it was still idling and cold but there is not much that changed. The O2 readings stayed close to the same. The idle starts at about 1500 RPM and as it warms up it goes down below 1,000, I am guessing around 800-900 RPM. It is fairly steady and smooth. No hunting.

So after driving for about 40 min I took this while on the highway driving at about 45 MPH (rush hour traffic) and trying to keep the speed steady. The second half of this graph was pretty steady.

http://tinypic.com/r/6id2tx/9

Then when I arrived at work I parked and let the car idle and took this last screenshot.
http://tinypic.com/r/125omee/9

I also took one with the RPM at a steady 2500 RPM when warm sitting in park. I can post that one if it would be helpful.

What strikes me about these is that the O2 voltage is sitting a little high? Is that true? If I remember right it should be around 450mV when warm? I guess this would explain why the fuel trims are low.

Thoughts?

Thanks Dave T

Well, the images did not exactly work well. MY first time trying to post pictures on the forum. I will have to figure this out later this evening.

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