My PP4 is finding it's way out of my tool box more and more.
While it does have some more useful features that the PP3 does not, there have only been a hand full of times I've used them. I've got other tests I use to verify driver integrity, and don't trust the accuracy of the meter enough to do min-max voltage testing. But once it's out of the box I'll use it all day. I'll be digging through test leads and figuring out how want to hook up my meter or use my test light without activating a ground side switched circuit and I'm just like "oh yeah, the power probe will do that!".
I have a pp3, use it ALOT. I've looked into the 4. It seems to me that at some point you cross a line to where a scope or dvom has to come out. In my opinion that point is between the pp3 and 4. Once I'm passed basic voltage. I like to have something deadly accurate. But, I dont own a 4. So my opinion may be nil. Just my 2 cents.
Power Probe isn't a great voltmeter, because they draw more current than s DMM or scope. All voltmeters put some load on the circuit and if the circuit is high resistance such as a speed sensor this will pull down the voltage. A perfect voltmeter would have s infinite resistance, a normal digital meter comes pretty close with a resistance of 10 million Ohms.
This why if you measure the voltage on wheel speed sensor with a Power Probe, a Scope and DMM you will get different readings but they will read much closer when checking battery voltage.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Eric O did a great video on the PP4. it's like an hour and a half long where he basically learns how to use it and does all of the functions on a live vehicle. I noticed he started using it a lot more after that video. You can download the user manual to see what some of the newer functions can do. I think it's a steal for $150.
I dont think there are big enough differences between the 2 to upgrade. If you were needing to replace then i would choose the pp4. I find it a great tool for quick tests and having several functions in the one tool is very handy but obviously for more critical work a scope is my goto option.
I really like my PP4 but if I already had a PP3 and knew what I know now I probably wouldn't have bought it. The extra features I don't really use. I see no good reason to upgrade from a 3 really. In my case the shop had a 3 but I wanted my own and for the small price difference I saw no reason NOT to get a 4.
Topic Author
I also own the PP3. I WANT a PP4, but can't justify it because of how infrequently I use the PP3. :silly: 
