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Tuning advice


Old Aug 8, 2018, 08:43 AM
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Tuning advice

I have a 2014 GSR with stage 3 mods and a tune from Rick at rallinspired.com. My idle is a bit off when rolling to a stop so I bought an AEM Wideband sensor in hopes of getting a better tune.

The mods are:
- MXP short 3" downpipe
- Ultimate Racing HFC
- Cobb cat-back
- AEM intake
- RRE boost solenoid
- Cobb Accessport v3
- AEM Wideband

I followed these directions to log my new wideband sensor:

Epic fail!

First off, my car doesn't have yellow and orange wires on the rear O2 sensor harness but pins 3 and 4 are red and green respectively. This is to be expected as it changes over the years. So I followed the directions and grounded the green wire (pin 4) and connected the white wire from the AEM Wideband to the red wire (pin 3). Nothing. No voltage to the ECU from the wideband and no CEL.

I then read on another forum that I need to reverse this. The green wire (pin 4) should be connected to the white wire on the AEM wideband and the red wire (pin 3) should be grounded. I did this and I got voltage to the ECU! I changed the monitor in the Accessport to AEM Wideband and it looked ok at first.

But problems.

After restarting the car, I got a CEL. Code P2252. I flashed to Cobb stage 3 just to make sure it wasn't something in my tune too but that didn't help.

I tried taking the ground off of pin 3 and that code went away but now it had a different code. I forgot the code but it was something about the O2 voltage was too high. The Accessport still logged the wideband but it was off. It was .5 to 1 off from what the gauge said.

So, I disconnected the wideband from the rear O2 sensor and put it back to stock so I no longer have a CEL.

I dug up an old netbook with Windows 7 on it so I'm thinking about selling the Accessport and getting a Tactrix cable and going with an open source tune. I'm not trying to make 500 hp from this car. I just want it drivable, reasonably quick, and reliable.

- Are there "off the shelf" open source tunes I can start from and then tweak as needed?
- Should I just stick with an e-tuner to reach my goals or is this something pretty simple to do given my mods?
- Maybe I should just stick with the Accessport and I just need to wire up the wideband differently?

What do you guys think?
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Old Aug 8, 2018, 12:54 PM
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The ground on your 4-pin connector should be the SAME location as the AEM gauge to prevent any voltage offset/discrepancy. Since you're dealing with 0-5v a small offset will cause issues.

p2252 indicates a negative signal is being fed. So at that point it' was hooked up backwards but with the right pins.

I'd try the wiring dance one more time and see if you can get it to work since quite a few others have had good luck.
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Old Yesterday, 09:00 AM
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I got it "working" sort of but it still had a CEL for voltage too high. The rear O2 sensor has a range of 0 to 1v while the AEM has 0-5v. So, it should be expected to throw a code for too high of a voltage.

But with a CEL, it doesn't really work.
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