AEM gauge flaking out

[kinger]

I'll try and test the sensor but all I get is "---" on the screen or 15.3 it flips back and forth. I dont get it worked great for 1500 miles this year now nothing. On start up it does sometime try to work then quickly goes to the above symptoms.

This what you guys typically see in a bad sensor, and how long do they normally last?


Running premium 91 fuel only no leaded race fuel ever unless Torco has it in which case I have used 3 - 32oz cans.

 

[mbarryracing]

The "---" is out of range, either below 10:1 or above 17:1.
When my sensor went bad it just read 14.8 and stayed there.

Unplug the sensor and the gauge should read 14.8 all the time, tells you if it's a sensor or wiring problem, etc.

Where is your sensor located in the exhaust? Check to see if the harness back to the sensor got smashed or pinched by the seat or tank, etc. I have seen broken wires in the harness to the sensor connector due to rubbing, etc.

 

[kinger]

I had it unplug once and it said 14.8 as well. ITs located just before the muffler in the rear. I'll pull it apart sometime.

What type of life do you get out of the sensor?

 

[zross1]

Check your ground. If that is good sensor could be out.

 

[mbarryracing]

I really can't tell you for sure. Just installed my new AEM AFR this season, only had 60 miles on it when it died, but I had been running 50/50 race fuel for a portion of that.
I just put a new sensor on and only have 40 miles on it so far, only pump fuel, so the jury is still out yet. Gonna get expensive if keep killing sensors...

 

[Nitrousman1]

I've heard of a few guys cleaning the O2 sensor with brake cleaner and having them start working again so it's worth a shot.

 

[mbarryracing]

I wonder how accurate the readings are after...

 

[kinger]

Its coming in the shop tonight, thanks for the suggetions I think i can at least do some easy things to see if its wiring or sensor related which helps a lot. I have all 3 gauges wired up to the same ground and power so its easy to spot bad grounds when they flicker (which I have had a ground loosen up on me once) but they have been fine. I sure hope I dont have to replace a sensor a couple times a year.

 

[grassracer2001]

Its coming in the shop tonight, thanks for the suggetions I think i can at least do some easy things to see if its wiring or sensor related which helps a lot. I have all 3 gauges wired up to the same ground and power so its easy to spot bad grounds when they flicker (which I have had a ground loosen up on me once) but they have been fine. I sure hope I dont have to replace a sensor a couple times a year.

mbarry.... got 1200 miles on my sensor this year, before you start the sled, turn the key on and let the sensor heat up, let it go though the numbers, this seems to take the moisture out, do the same thing when you turn the sled off. p.s.. your missing some good riding down here.

 

[mbarryracing]

Maybe I need to quit monkeying around here on this POS and get down there riding with you!

 

[kinger]

Found the problem it was a bad sensor, luckily I have a spare and swapped it in. So 1200 (nto 1500 like I thought) and its bad. running all premium fuel and 3 cans of torco with 87 gas is all it saw.

 

[mbarryracing]

Take grassracer2001's advice on allowing the O2 heater to warm up before firing up the engine. There is so much moisture produced in the exhaust from the combustion process in these sleds that the sensor located near the back gets douched pretty good. I get water actually spitting out the tail pipes on my Apex until it warms up fully.
In automotive applications, the sensor is closer to the engine so it see's less moisture in the exhaust at that point. The gasses havn't had a chance to cool and condense yet.

 

[kinger]

I will do that from now and see if it helps! Thanks!