I need help here guys. Every time I hook up my Air Fuel gauge my check engine light always comes on. I have spoken with another maxima guy and he gets the same thing. I already tried hooking it up to the rear O2 sensor and front. Is there a certain way to install these with out that light coming on?

Thanks,

NeL

 

Does the guage work? Maybe you grabbed the wrong wire. If you have cats you can't use the rear O2 you must use one of the fronts but it will only read 1 bank. I have a test pipe and hooked mine up to the rear O2 with no prob. BTW, what year is you max?

 

Thanks for the quick responce.. My car is a 97 SE. The gauges are Auto meter Phantoms. I know the gauges aren't broken. What wire did you hook yours up to on the front O2 sensors? I hooked mines up the blue one. Thats the only one that i'll get readings from.


Thanks again,

NeL

 

Well I hooked mine up to the rear 02 because I don't have any cats in my car but you probably do so you'll have to use one of the fronts which read exhaust before the cats. See if you hook it up to the rear the guage won't read rich/lean, it will stay in the middle because the rear 02 sens is after the cats and is used for catalyst effeciency testing. The easiest way is to go to the ECU (under the center dash kick panels) and splice into -do not cut- the 02 sig wire. Left front is ECU terminal 51 and R/F is 50. I have a pic of the ECU terminals. I will try to EM it to you if you like because the site I use to host photos is down right now.

 

You can splice them up to the factory ECM wiring behind the radio on the floor. You can approach it from the passenger side. You can splice them to either #51 or #50 IIRC (you will need the diagram but I don't have it scan in and available)

 

Thanks guys for the replies..Maximus75 if you can send me that pic that would be great. If you'd like just email it to me Nelson_Burgos@yahoo.com

Thanks,

NeL

 

Hey, is there an echo in here? Chunger, is that a carpet on your dash? Anyways, PRPMax, you've got mail.

 

LOL... no just a constant server busy message... you beat me getting though... Yes... I have a dashtopper thingie..

Someone should post the ECM wiring diagram on the FORUM as a sticky!

Send me the diagram too and I'll put it on my webspace for reference.

 

No prob though its kind of a sh!ty pic. Give me your EM adress

 

When you check engine light comes on, you should try to see the error code. You can do that by turning the screw on the ECU clockwise then counter clockwise (after 2 seconds). What I suspect might be happening is that the gauge is loading the sensor altering its output slightly. If you have a multimeter you can check this by probing before and after you attach the wire. The ECU will think that you are running too rich or lean based on the reading from the sensor output. If you check the error code, I might expect a 114 code (I think) too rich or lean (don't know code for lean).

HOWEVER, I have not heard of other people having this problem. You may want to check your ground wire to make sure it is properly grounded.

I have just installed the gauge but not actually hooked up the connections yet .

 

 

uh, i wired mine straight to the ecu, but i didnt use either of those you mention, i use one on the row beneath it. I get great results, no problems......

 

Thats for the rear 02, won't be accurate if you have cats.

 

Hehe! A/F ratio gauges are rarely accurate anyway! EGT is the best IMHO.

 

I know last weekend I hooked my a/f gauge up to the rear bank o2 sensor. I tee'd of the black wire at the connector leading toward the o2 sensor and the gauge works great, jumps all over the place, but works none-the-less. However, if I would have known to hook it up to the ECU...I propably would have gone that route. I may be making a change this weekend...

-Josh

 

This is true

 

i tapped into the white wire (one of 3) of the connector in the front of the car. is this right? whats the difference between 50 & 51?

 

what about dogs?
anyway, basically you have a y-pipe w/o a cat, just a pipe there right??

 

Jeff,

whats the best spot you think to tap into for the AF gauge. Im really not looking for the most accurate, just the most convinient spot to grab the readings from

Ant

 

You know I tried spliding into the ecu and just could not find the right wire and I consider myself capable of this type of work and more but it just did not work...I saved myself the headache and wired it directly to the 02 sensor lead wires...the non-shielded ones in the engine bay just above the exhaust bank.

 

On my car i have two separate plugs right in front of the valve cover. One of them has 3 wires in it, a red/black, blue and white someone told me to use the white wire off that harness for the AF gauge. Also i noticed that those 3 wires go down into another wire wich looks exactly like an o2 sensor wire headed tword the exhaust-manifold so im hopin that this white wire will do the trick for me

Guess ill run a lead off that white wire into the AF gauge while im under the hood just to test out if thats the one or not.

thanks,
Ant

 

If you have a Y-pipe, I would install the O2 sensorat the end of it right before the cat. This way you'll pick up both banks and the signal won't be altered by the cat.

 

it looks cool though