STS Twin Turbos

[Rich Z]

Originally Posted by Gannet

It's always something, innit?

How are you doing this data logging?

I've got HPtuners, which personally I think is worth the money just for the data logging it can do. You can set it up to capture just about anything you want, then play it back after a ride and watch what is going on.

For instance, here's a capture I did before I took the car down to AntiVenom for the STS install:



Notice the white line for IAT (incoming air temps)? Something DEFINITELY wrong there. While driving at a constant speed, the IAT values were spiking up to 259 degrees! While obviously cannot be true, so there apparently was a problem with the IAT sensor. Greg checked it out and found a corroded pin on the sensor that he fixed. This could have played hell when Greg was trying to tune the car had I not had this info on hand.

I can't think of anyway else I could have ever known about this sort of a problem. With the data logging and looking at the display graph, it is OBVIOUS.

Same thing now with the misfires. It is glaringly obvious when you see them on the graph. Now I just have to try to find out if it is only one cylinder with a problem, or random misfires from multiple cylinders. I set up the data logger to try to figure this out for me.

So we'll see....

[Gannet]

So you are logging to a laptop while you are driving? Is that how that works?

How hard is it to hook up the laptop when you want to do that?

[Rich Z]

Originally Posted by Gannet

So you are logging to a laptop while you are driving? Is that how that works?

How hard is it to hook up the laptop when you want to do that?

Well, yes, you can do the logging with the laptop, but with the professional version, you can do standalone data logging with the cable only and don't need the laptop hooked up. The cable has a black box wired into it, and you just plug that into the PCM port and whenever you want to start capturing, just press and hold the RECORD button on the black box for two seconds.

When you get back home, you hook up the cable/box to your PC via a USB cable and download the data to view with the scanner program. REAL easy to use.

Matter of fact that's what I did today and just need to download the data and then view the log to see if I can get a better handle on what is causing the misfires.

Bear in mind that I am a "wet behind the ears newbie" with this thing, so if you want some more in-depth info, you may want to jump on over to http://www.hptuners.com to see what you can find there. They have a very active forum on this stuff, but honestly, most of it goes RIGHT over my head. Heck, I just learned yesterday what 1 bar, 2 bar, and 3 bar MAP meant!

[Rich Z]

Here's a graph from a run I did that is showing when the turbos kick in. Can't say I can explain all of the lines on the chart, but I think if you stare at it long enough it starts to make sense....

[Gannet]

Faskinatin'. It's clear I need to get one of those software packages.