Using the SCT tuner to diagnosis a car

[hades_1]

Hi there, I spent some time yesterday trying to find tutorials on how to use a SCT tuner to diagnose your car but I didn't find all that much. Is there a website with such a thing?
I know how to diagnose the IMRC on my 96 Cobra, which is a good start, but I'd like to know more especially on how to check MAF; how to compare stock vs bama tune (what has changed? is it a safe change?); and more importantly how to check the catalytic converter (I think I lost some power and my exhaust is quieter than it used to, so I am suspecting the cats, but I am not sure how to check them with a tuner)).

That being said, a sticky with the most common ways to diagnose your car with a tuner would be great on that forum for any newbie.

Thanks!

 

[01yellercobra]

You can use the handheld to check and clear DTC's (Data Trouble Codes). It can also be used as a pass through to datalog using SCT's Livelink. That's how you would check your MAF. You'll need a seperate wideband to check and compare the A/F change. AFAIK you can't check a cat with a tuner. At least not on our cars. You'll have to actually remove it and check it out.

 

[hades_1]

Ok thanks, I didn't know about the cats. That sucks.
Yeah, I have been using Livelink, and it's working great, but I am not sure what to look for exactly, which is why I was wondering if there was some guides on how to use LiveLink to troubleshoot our cars.

eg: to check the IMRC functions properly: get RPM, imrc bank 1 and 2 and if they get around/ under 200 when the RPM goes above 3400 RPMs (IMRC are open) and around 1000 when the RPMs drop (IMRC are closed).
Things like that.

 

[01yellercobra]

You just have to select the PIDs you want to watch. Which is going to change depending on what you want to troubleshoot. For tuning I watch MAF counts, FP duty cycle, spark source, spark advance, STFT's, RPM, and I have a wideband hooked up so I can watch A/F under WOT. I have other things I watch like battery volts and idle integer just to keep an eye on things.

 

[hades_1]

Yes, I think I am getting which data I need to collect, more or less. What I am not sure what to do is how to interpret this data and what they actually mean.
I guess I could post some screenshots and ask peoples to help me understand all this...