Tuning help needed - '91 TBI 383 w/ Vortec heads

[donf]

No android phone, I use an iphone. I'll just stick with windows laptop/TunerPro/ALDL cable. But thanks for the tip.



Hmm, thanks for the tip. Might try that.

Guys, I've thought about disabling closed loop just for diagnostic purposes. I'm curious to know if these decel surge issues are still present in open loop - seems like if they're not that would help me zero in on the problem at least a little more. Can I just unplug the O2 sensor or should I do the disabling in the BIN? If BIN do I just increase the timer a big amount?

And one other thing I'm trying: have a new MAP sensor on order. I'm not big on throwing parts at problems, but I found a NOS GM on ebay for $15. MAP is one of the few things I reused after my rebuild and I just want to eliminate that being the problem.

There are different ways to end up with different results. Look at the voltage shape of the typical narrow band o2 sensor. You may be able to get you block learn dialed in and its fine for that, but what about your WOT mixture that's not suppose to be Stoic?? After all you have put into you project do you really want to skimp with $160 and a few wires to log the data? If money is that tight, sell it on craiglist when you are done. No one will ever say a narrow band is superior for tuning, you may be able to "get by" but really for the money involved, why? I did not want to bother with mounting a gauge or cutting holes so the new AEM line has one that just data logs to a computer. The accuracy is very close to the big $$ Haltech setup on my chassis dyno.

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[Kitch]

Have you blended your main and idle spark tables in the areas where they crossover (I'm assuming you have tracing turned on)?

[Daveo91]

Have you blended your main and idle spark tables in the areas where they crossover (I'm assuming you have tracing turned on)?

Thanks, no, I have not been using tracing. But I just read the help section in TP on that and I'm definitely going to start using that feature, assuming I can get it to work. Sounds like the ADX and XDF have to have values linked between them - not sure if the ones I've been using have that.

[Daveo91]

There are different ways to end up with different results. Look at the voltage shape of the typical narrow band o2 sensor. You may be able to get you block learn dialed in and its fine for that, but what about your WOT mixture that's not suppose to be Stoic?? After all you have put into you project do you really want to skimp with $160 and a few wires to log the data? If money is that tight, sell it on craiglist when you are done. No one will ever say a narrow band is superior for tuning, you may be able to "get by" but really for the money involved, why? I did not want to bother with mounting a gauge or cutting holes so the new AEM line has one that just data logs to a computer. The accuracy is very close to the big $$ Haltech setup on my chassis dyno.

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I get it that WB is superior for tuning outside of closed loop. Not arguing and, no, money is not that tight. I just haven't gotten to it yet. I have other projects and I stagger the time and $$ I put into all of them. Suburban is drivable as is so it's not number one priority. Am looking around online for a WB kit, but in the meantime I don't see the harm in spending $15 on a new MAP to see if I can rule that out, same with forcing it into open loop and taking a short test drive. I'm still concerned I have some unresolved mechanical issues, too.

So some beginner questions on WB.... You mention you're not using a gauge and just a single wire into a computer? How does that work, is it a USB? Does it sync with the log file from the ALDL/ECM output? If not how would you reference it back to time-based events like a throttle stab?