OBDII Data for healthy engine
 

Firstly, apologies if this is elsewhere and my searches haven't found it as I don't know the right buzzwords.

Please can someone show/tell/steer me to OBDII data logger output for a healthy 231 engine generating good power that I can use as a reference, primarily against data taken by an OBDII port dongle transmitting to a Netbook with appropriate DIY software or, if better, a Nexus 7 or an iPad with appropriate apps.

I know there is some data in the workshop manual, for example some for ignition timing, but what I can find falls short of what I want to check my car's data against.

I ask as I have a 2006 231, engine mileage unknown (car is 90k but the engine number doesn't match that on registration document) that I think is down on power despite service, new plugs, leads, coils, air filter etc, MAF clean etc) as the best times I can get are 7.8 secs 0-60 indicated and 5.4 secs for 50-75 in 3rd gear. Compressions are pretty healthy (all between 7.0 and 7.5 Kgf/cm2 normalised to 250 rpm), there are no fault codes, the cat is fine (I changed it to check) and there are no hesitations.

BTW please use simple terms and be nice to me as, despite enthusiasm and my best efforts, I struggle with anything containing software (my brain was finished before I met it and it always seems to go wrong for me).

Thanks for any help.

Ian;

Honestly the compression test is the one that many people rely on for basic engine health. Other than that, there isn't too much obd2 data can tell you about the overall health of the engine. OBD2 data is typically gathered from various sensors in the vehicle... this data can vary from car to car especially cars that have been modified as these sensors could have improper scaling.

Is there anything in particular you are looking to test for?

Thanks.

I was going to start with mass air flow and a comparison to see if anything stood out. About the only thing left for me to check physically is the exhaust for any blockage by taking it off and/or swapping it out, but that's a long shot as the original cat was in one piece and I can't get any rattles from the exhaust in situ. I've got wider wheels on and hence a heavier/greater inertial mass but they made less than 0.1 sec difference on my other RX8s (this is my 5th 231 (3 S1s and 2 R3s)).

What else are you looking for?

I just spent 15 min doing a reply on my phone then lost it all (typical frustrating experience for me) so my answer until I can get to a PC is "anything that I can check with DIY kit, ie not needing Mazda specialist kit".

Thanks, and apologies if my response is short, figuratively and literally.

Investigation temporarily suspended.

I found a user manual for my OBDII data reader yesterday. I used the netbook for an hour or 2 on other things, shut it down and opened it up a few hours later to follow the UM. Alas, the screen remained blank and wouldn't come to life no matter what I did. I then got a proper display by connecting the netbook to a monitor and I spent a miserable 2 hrs checking every connector and wire without success. I then spent another 2 hrs helping my mate investigate the problem until he, too, gave up. After a few tears of frustration and a beer I accidentally knocked it off a table. Now nothing on it worked so we spent another hour checking without success. Alas and alack, I'd had a really bad day on other things and in a moment of mad frustration I lashed out to close the lid and succeeded so well it crashed into a wall. I lost the plot and threw it on the floor. It was then completely f'cked and I cried for the first time since I can't remember when.

Someone please wake me from this nightmare.