Ground Point for AEM Wideband...datalogging issue

[JSchleim18]

I wired in to the pin 15 slot on the ECU to get a wideband reading through my datalogger (MMcD v1.8g). The reading is about .5 higher from the actual AEM wideband gauge.

Where is the best grounding point in the car to get a more accurate reading out of the datalogger and to avoid any noise interference from the radio? When I turn my radio on I get the ill-fated whine.

Thanks

 

[4thStroke]

When you tapped into pin 15, was that pin open on the harness side?

Mine didnt have any contact on the harness side, but it did on the ECU.

 

[JSchleim18]

I took the pin out of the ABS wire (blk/white) bc I don't have ABS. I then stuck that pin into pin 15 and clipped the wire. Then I wired in the white wire off the AEM gauge (0-5v) into the pin 15 of the ECU which is now a blk/white wire. The harness side is "hanging loose" aka not wired in to anything.

 

I have the SAME fricken problem. My wideband will also decide to not work for a couple hours and then work again. Irritating as hell!

 

[1990ggsxnj]

Which Wideband are you using Shiskibob? Curious if it's AEM

 

[spooling92vr4]

your supposed to ground the wideband to the battery itself according to aem's directions

 

[JSchleim18]

I may just do that to get a more accurate reading, but when we tested the connection on the battery, it still whined.

 

It's the AEM. I called tech about it and they said for $30/hr and shipping charges, they would diagnose the WB unit itself. I hung up.

 

[NateCrisman]

There is always talk on the DS-Map board that the AEM wideband 0-5V output is not consistent with the gauge display when using the volt = a/f formula or chart they supply. It may just always be off by a few tenths of a point due to AEM's incorrect data sheet.

 

[JSchleim18]

Well at least my radio drowns out the noise /ubbthreads/images/graemlins/dunno.gif. Looks like I am stuck guessing on the values. I appreciate the help

 

[onesickcrx]

My AEM wideband does the same thing. What I ended up doing was figuring out how far off it was. My gauge was saying 11.2 and dsmlink was reading 11.6 . I borrowed a innovative wide band to verify that the AEM gauge display was correct which it was. So now when I log I know 11.6 it is really 11.2 .

 

[iLLeffeKt vr-4]

Do you guys use the ecu input buffer from dsmlink? I have it in my car along with the AEM wideband and DSMLink and have no issues.

 

[JSchleim18]

^^^What is it exactly? I am only on a KD chip...no link here

 

[iLLeffeKt vr-4]

You can read more about the buffer here and here .

 

[JSchleim18]

Hmmm that seems like the possible answer. Anyone else have any insight on this?

And thanks Adrian I hope you liked the car

 

[iLLeffeKt vr-4]

I like the car. I don't know how it was when you first got it but I'm sure it came a long way. You were also set back when it was broken into and you did a good job fixing everything.

 

You also may want to consider using the sensors ground (pin #24) of the ECU as the ground for the wideband, since the ECU references everything to that ground.

 

[JSchleim18]

^^^I'll ground it there first and see if the noise goes away or I get a better reading. The "buffer" grounds it to that pin location as well. Thanks Jeff