AEM A/F gauge install - problem

[77srxdude]

I installed it and attached the power and ground to the same power (yellow - also added 10 amp fuse) and ground (black) coming off the headlight which I used for the stoich gauge previously on the sled.

Start it up, the guage lights up with some weird stuff and goes right out. I tried with the sensor unplugged and same result. I was in the garage so I didn't run it long. Around 30 seconds. Does it need to run longer?

Should I be tying into a different power source? The stoich required 12v, just like this AEM gauge.

One other thing - I just read this in another post not to shorten the wires to the sensor. Well I had to add around 12" of wire to all 6 wires. Did I just screw myself?


Thanks in advance.

 

[mbarryracing]

So the readout on the gauge goes out?

When I start my sled, my AEM AFR gauge displays a value like "P00" or something like that and then "14.8" until it starts to warm up, at which time it quickly cycles down to "10.0" then back to up "14.8" then slowly climbs to full lean "17.0" then "---".
If the sensor is unplugged it reads 14.8 continuously.

Yours does not do this?

BTW, I have the red power wires tied together and into the brown ignition power from the key switch harness. The blacks are tied together and soldered into a ring terminal and grounded on the chassis hoop.

You shouldn't shorted the wire harness for the sensor lead, doesn't matter for the wires coming from the gauge readout itself (like for the 0.5v output, serial output, power, and ground).
If your shorted the sensor lead, the calibration gets funky because the resistance is different thru the different distance of copper wire.

 

[77srxdude]

I get no reading at all. It just lights up and the bottom half of the numbers flash on then everything goes out.

I got to thinking and it was the light for my boost gauge that was attached to the headlight wires and the power for the stoich was tied in to a line I had going to I believe the key (along with the fuel pump).

I will try swithing the powwer over.

Any thoughts on lenghtening the sensor wires? IS that going to screw up the readings.

 

[mbarryracing]

Any thoughts on lenghtening the sensor wires? IS that going to screw up the readings.

Bad, like I said the resistance thru copper changes with distance.

 

[77srxdude]

For what it is worth - I just got off the phone with AEM and they are telling me if the wires are extended or shortened it shouldn't matter. What will matter is the splice job of the wires - if done well, then no problems, if not, then you have issues.

Gotta love this stuff.

 

[mbarryracing]

Make sure you ground the leads separately to the chassis somewhere, maybe even jumper the power directly to the battery pigtail to make sure the gauge atleast works correctly.

 

[77srxdude]

Thanks for the suggestions mbarry,

Talked to Jannety now too. He says the same as AEM, doesn't matter lengthening or shortening the wires to the sensor - just do a good job of soldering and heat shrinking.

Going to move the power and ground to where my stoich sensor was wired in previously and hopefully all should be good.