I'd probably only advise using data gathering / diagnosis is the car is heavily modified, otherwise you probably won't be looking at much interesting.

I've seen people get tangled up in looking for problems which aren't there, due to a minute difference from one reading from one day to the next. Plus the car is pretty reliable and faults are quite rare.

They are useful when you do a fault though - and really all you want to see is the voltages from the main sensors.

If you want to play with graphs and things then i'd suggest something laptop based. Never used any so can't give any advice there (i've never needed more than a fluke on a modern car)

There are some good books out there too - there was a Haynes one on engine management from memory.

 

I'll likely just stick with your initial advice then I think..

Cheers

 

for me I was interested in coolant, ign timing, fuel trims, map etc bit that's because the car is modified.