I'm new to data logging, using WinALDL. I have an idea of what I am looking at, but I'm still unsure about a lot.
At idle, my O2 readings bounce from .008 to .9. I get a rich flag when around .9, and then it drops to about .5, then to .0, then back up to .8 or .9. Seems wierd. Think I need a tune up?
This is an LO3 with dual snorkel intake, otherwise stock (Unless previous owners played with it).
And just to clear this up, BLM above 128 means it is lean and the ecm is adding fuel, and below 128 means it is rich and ecm is taking away fuel. Right ?

Thanks.

 

The bouncing is normal, it means that closed loop is working.

Your fueling looks to be OK, just a little lean in the accelerating 1400-1500RPM 60-65kPa MAP. You're right about higher BLM is lean. I'd try to get it below 128 everywhere, and try for a range of 6 or 7 from leanest to richest.

You're getting some knock, though. Seems like it's knocking with almost any load. Have you increased the spark timing a lot?

 

I have never checked the timing on it, so it could be high. I think it definetly needs a general tune up, it doesn't like to rev above 3200.
How do you know it is knocking from the data?

 

Knock counter increases during load.

 

Wow, i am new to this. I didn't even see that.

Do you think the knock mite have something to do with bad ignition? I had trouble passing emissions two weeks ago and a mech recommended I get a full tune up, but I didn't ahve the money and another mech found a way to pass it.
I'll give it the tune up and check the results.

 

Check the base timing first, always. Remember that that is done by disconnecting the EST bypass wire (tan with black stripe, usually, and with a single connector somewhere near AC junk near the firewall in the engine bay, at least on a TPI, not sure on TBI), and checking the timing at idle. On a TBI, I think it's supposed to be 0, or 6. Check the emissions sticker under the hood - it should say clearly. Too much timing might cause an emissions failure, especially if it's the dyno type. Bad ignition components on electronic ignition usually don't cause knock though, as far as I know.

 

I checked my timing. Its a 0 degrees, right where it should be.

The only thought I have on my knock counts is exhaust leaks fooling the ecm?

I friend of mine with a 3000GT said he had problems with phantom knocks when his turbo to exhaust wasn't bolted tight.

Think my old exhaust is causing phantom knock?