Can someone give me a quick primer on data logging?

[Davyhay]

What's the best software, interface cable, etc?

[jester17]

I just yesterday got in the mail my OBDCOM unit, which was easy to install on both computer and car -- lots of good data both while driving and in 'run' mode. Of course, I'm a totally N00b, and just bought what I saw recommended on-line... but it was $80, got in a few days, and, as stated, easy to work with.

[135Pats]

Let’s start with what tune you’re running, and go from there

[Davyhay]

No tune on the car. I want to log to make sure the car is 100% before I begin to tune.

[135Pats]

Originally Posted by Davyhay

No tune on the car. I want to log to make sure the car is 100% before I begin to tune.

Commendable and that’s a good attitude to have, but if the car is running strong stock, you shouldn’t be worried about the “stg1” type tunes. There’s nothing 14psi midrange will break that 9psi midrange won’t, nothing catastrophic at least. So to figure out which parts aren’t up to snuff (if any), you need to stress them. You’re being overly cautious here. Pick a tune that you want (that’s an entirely different discussion) and go from there. All the major options have logging capabilities integrated, though depending on whether you go piggyback vs flash, the number of values you can log are limited.

[Davyhay]

Gotcha. The car is not running strong and thus my other thread regarding the car being down on power. I am coming from a MKiv Jetta with a mild tune, so the car clearly seemed quick to me. It has been about 4 years since I sold my E46 M3, and the car seemed on par with that.

However, when I took it to the track, the ET and trap speed told otherwise. If I can get the car running mid 13's stock, I feel I'll be comfortable modding. Otherwise, it seems the $500 I have tucked away for a JB4 would be better served fixing issues. I will be replacing spark plugs and vacuum lines this weekend and I'll be doing the ever-important walnut blasting within the month. Hopefully, this will get me to where I want to be.

My worry is the turbos. I can't detect and hint of what I would consider actuator rattle at startup. The only thing I hear at startup is a perfectly rhythmic tapping that sounds like vales. This lasts for about 30 second and goes away. However, I don't see where the turbos have been replace on the service history, so I am paranoid as hell.

[135Pats]

Originally Posted by Davyhay

Gotcha. The car is not running strong and thus my other thread regarding the car being down on power. I am coming from a MKiv Jetta with a mild tune, so the car clearly seemed quick to me. It has been about 4 years since I sold my E46 M3, and the car seemed on par with that.

However, when I took it to the track, the ET and trap speed told otherwise. If I can get the car running mid 13's stock, I feel I'll be comfortable modding. Otherwise, it seems the $500 I have tucked away for a JB4 would be better served fixing issues. I will be replacing spark plugs and vacuum lines this weekend and I'll be doing the ever-important walnut blasting within the month. Hopefully, this will get me to where I want to be.

My worry is the turbos. I can't detect and hint of what I would consider actuator rattle at startup. The only thing I hear at startup is a perfectly rhythmic tapping that sounds like vales. This lasts for about 30 second and goes away. However, I don't see where the turbos have been replace on the service history, so I am paranoid as hell.

Swapping plugs is almost never a bad idea. Are you feeling misfires? I need more context here in terms of what’s wrong with your car. If it’s throwing SES lights it’ll have stored codes that can be read by any old OBD tool.

And turbos going “bad” could mean a bunch of things. WG and actuator rattle is sadly just the name of the game, it doesn’t mean your turbos have failed in the sense that they no longer deliver requested boost. Do you have oil consumption issues?

A lot to consider here