How do I know if my car's been tuned?
 

Hi all!

I bought my car from it's second owner who knows nothing about cars and who never talked to the original owner. When I purchased it, the car had an AEM cold air intake, Kinetix Racing V plenum, headers (can't tell brand), and Tanabe Medalion cat back exhaust. What I'm wondering is how to find out if the first owner had the ECU reflashed. Any thoughts?

No way to know for sure except for getting a tune/retune yourself.

I was afraid of that. Is there a way to do this by datalogging without having to go through he expense of retuning?

You should look into getting a tune anyways. With all those parts it would be beneficially to do it anyways. You can get an Osiris UPREV tune for like avg. $550, in the world of G35 parts its not bad considering it takes full advantage of already installed parts. I got great results from UPREV. check out my thread 276HP265TQ SAE

Yeah. That's why I'd like to know if it's already been done. I don't want to show up at the tuner and get screwed for something that's already done. If it's not, I definitely want it! I've been reading a little more and looks like for about $200 I can get Cipher and cable. I'll be able to see my tune and actually change some stuff (idle rpm's, 2 degree timing) but, will I be able to compare my tune state to stock? Also, will what's available on Cipher be enough of a tune for my mods?

The Cipher is a good tool for data logging and diagnostic not really tuning as in actually making changes. While yes you can data log all different engine parameters there is not much you can do to change what is already programmed more just watch than anything. While yes you can clear learned fuel settings this really is not much control at all over the fuel system.

Also unless wide band(s) have been added to your car there is not really much you can do with the factory narrow bands for tuning other than checking if you mixture is rich or lean. Factory narrow bands really only display if the air/fuel mixture is above or below a stoichiometric mixture (14.7 AFR).

Wide bands will display your current AFR at all times from a range of 5.0-22 AFR usually. 5.0 AFR being extremely rich and 22 AFR being extremely lean. You can hook these up to the cipher (make sure compatible) to compare the AFR with other engine parameters (RPM, Knock, Air/Coolant Temps, Timing, etc...) which you can watch in real time and can also be log and referenced at a later time.

You might want to look into the Osiris Standard to start out. It does includes the Cipher and in addition it will also allow you to alter up to 5 different Maps. Some of the things you can control are AFR Targets, Ignition Control, Fuel Control etc. Check out UpRev's site.

Please be careful though, if your tune is not correct it can result in engine failure. A professional tuner would be your best bet.

Thank you very much for your input.

Nice post, just a couple corrections though.

Cipher/Osiris does NOT support 3rd party widebands at all.

On the other hand, 04.5+ G's and almost all Z's have dual factory widebands which are logged by Cipher (mine included).

Only '03 and early '04 G's have narrowbands only.

Sorry for my inaccuracies.

I did not know that 04.5+ come with factory wide bands. I have a 03 :( lol