I'm looking at some Bonnevilles this week. Both NA and SC in the '97-'99 range. i have a scantool that i have used for simple problems on Toolgirl'* Explorer and me Bonne. I just don't know the scope of the tool.

It'* an Actron 9145. It can pick up the regular trouble codes, and pending codes. It will pick up the GM specific codes. I don't believe it picks up "enhanced codes".

My question is, can i still miss something crucially and crtitically wrong with the car because I won't get at least a hint from the codes? this assumes that I will do the proper visual and driving evaluations.

99% of the time you will never see anything majorly wrong just by scanning....unless there is a code

Maybe I'm off in the wrong direction with this scantool. let me back up. I want to run the cars to pick up the emission and available sensor data and see if any trouble or pending codes appear.

For example for the tranny.. I'll check the fluid, and for leaks, then drive the car for smooth but firm shifts under different gradient and speed loads. It feels good, fine. But then I want to check it with the scantool to see if there is some code(*) of something wrong with the transmission under the covers that I didn't (couldn't) pick up from test drive.

Is this a valid use for the scantool?

If there is a history code or new code, yes..it'* always helpful to scan it.

This past weekend I got my autotap and a buddy wanted to go look at a little truck. His friend had "told him everything" about it. When we got there and he saw the pc come out to be hooked up, a little more of the history on the truck came out. It scares most people into mentioning things they normally would "forget to mention".

Even stuff that doesn't matter...

If you have one that gives real time data, and you know what it means, it couldn't hurt to plug it in on your test drive.

If its an Actron CP9145 - you can plug it in and record your diag when your driving for review later.

http://www.amazon.com/gp/product/B00...333?n=15684181

Oh, yeah.... I pulled it out at a dealer today and plugged it in. Th expression on the salesman'* face changed to . In fact he almost left skidmarks when he took off inside "for a moment". I guess he wanted to ask the sales manager what i was doing. I was actually fumbling through it as im just getting used to using it and and this was the first OBDII car I had put it on. Got values for some diagostics, now I have to research their proper ranges. Didn't get any codes, but i didn't tell him anything.

That Autotap looks really cool. It'* way rich in info for my level right now. But someday...

I can get some realtime data with it, nothing like the tools the savy performance guys can pick up. I'll have to research the significance of the data, and that'll be a fun part of the learning process. Even if i do catch a code, I think that can be just a hint that can point me towards an involved diagnosis process to really know what the problem is. Or something very specific. Not that I would pursue it.. just so I know something is up before i lay down any green for the car.

OT- the tool was really helpful in figuring a problem with my wife'* ABS. There are 4 wheel sensors plus a nasty sensor on the transaxle. I needed to know if it was one of the sensors or if the actuator had crapped out. Which would have been a million dollar repair.

Autotap is nice, but 99% of the people in the world will never need the data or have a use for it.

My middle name is usually overkill ...

Yeah, i just need to know that a cylinder is misfiring. I don't need a count of misfires and analysis graph. But the Autotap software does give direction through a level or two of analysis when trouble comes up.