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sixfiveoh
08-24-2007, 03:33 PM
I'm using the A'pexi turbo timer which is also an A/F meter. Is there any DIYs or walkthroughs on how to hook one up? I assume you wire it to your o2 sensor? Anyone know how the A'pexi reads out A/F ratios? Will it show the actual ratio, i.e. 14.7:1? Or what does it read out?

[up]

dukez
08-24-2007, 03:47 PM
No idea about the reading, but when you connect it to the O2 sensor, its the sensor in front on the cat, and its the black wire. [:D]

sixfiveoh
08-24-2007, 03:56 PM
Just did some searching, and it appears that it will read out merely with the air ratio (10.00 being rich, 20.00 being super lean). I have an 01, I heard of some issues with the 01s and A/F meters, will I be fine with simply tapping into the black wire?

Another question, where did you run the wire from the A/F meter? Our cats are right below the exhaust manifold, right? Do you run it thru the firewall, then down thru the engine bay?

pac1085
08-24-2007, 05:38 PM
The 01's have a wideband O2 sensor which works totally different than narrowband o2 sensors. You can not hook it up.

sixfiveoh
08-24-2007, 05:46 PM
So why can't I hook it up? The A'pexi can't read wideband sensors? What will happen if I do hook it up, and what meter should I use that will work?

mike-2ptzero
08-24-2007, 06:12 PM
Because you can not just splice into the sensor wire of a wide band because it is self heading. If you want to hook up your APexi to read 02 readings you would need to use a narrow band 02 sensor. The other thing you could do is buy a wide band setup that has a analog output that you could then hook up to your apexi.

But the best thing to do is just to buy a wide band unit that comes with its own gauge, you can find a good price on ebay for a Innovate unit that comes with a digital gauge. This is the gauge setup.
http://www.innovatemotorsports.com/products/images/DBkit_Dual_700.jpg

sixfiveoh
08-24-2007, 06:27 PM
Oh, I see. So wide-band gauges actually come with their own o2 plug?

sixfiveoh
08-24-2007, 06:34 PM
Goddamn, those are expensive. I guess it's not something that's necessary, just something I'd like to keep track of every once and a while. Can vagcom log a/f?

bassed
08-24-2007, 06:40 PM
Oh, I see. So wide-band gauges actually come with their own o2 plug?

Yup you need another bung on you TP/DP to accommodate. Yes you can log with VAG, it's not as accurate, but for a car in stock form it's all you need. Save your pennies for now.

mike-2ptzero
08-24-2007, 06:41 PM
Goddamn, those are expensive. I guess it's not something that's necessary, just something I'd like to keep track of every once and a while. Can vagcom log a/f?

Yes you can log a/f with the vagcom, it is block 031 for lamda or 033 for voltage. You want to use block 031 and multiply the readings by 14.7 to get your AFR.


Yes those gauges are expensive, but they can be found on ebay for about about $260. Yes the wide band units come with their own 02 sensor, you just have a bung installed at the bottom of your down pipe.


If you are just looking to keep track of it now and then just use the vagcom, because a wide band unit must be on any time the engine is running or the 02 sensor goes bad and the 02 sensor costs $80 to replace.

sixfiveoh
08-24-2007, 06:42 PM
Wait, so in addition to the o2 plug that comes with the wideband gauge, you also need to keep your stock o2 plug and put it somewhere else?

bassed
08-24-2007, 06:52 PM
Wait, so in addition to the o2 plug that comes with the wideband gauge, you also need to keep your stock o2 plug and put it somewhere else?

You keep both OEM O2's in their respective stock locations and add a third bung like Mike and I said for the Wideband sensor. So you have 3 o2 sensors on the downpipe.

sixfiveoh
08-24-2007, 07:16 PM
Oh. You have to actually ADD a hole? There's no pipe you can get pre drilled for 3 o2 sensors?

urban96
08-24-2007, 07:29 PM
an exhaust shop shouldnt charge more than $15-20 to weld in an extra bung. also if you have a cat still it MUST go BEFORE the cat to get an accurate reading. also you dont want it welded straight up from the bottom, most companys recoment between 3 o'clock and 9o'clock so that moisture dosent kill the sensor

mike-2ptzero
08-25-2007, 12:40 AM
Doesn't really have to be before the cat, when you run on the dyno they put the 02 sensor at the end of the exhaust and still get a accurate reading.

urban96
08-25-2007, 01:50 AM
step 4 page 5

http://www.innovatemotorsports.com/support/manual/LM1_Manual.pdf

mike-2ptzero
08-25-2007, 02:33 AM
step 4 page 5

http://www.innovatemotorsports.com/support/manual/LM1_Manual.pdf

Yes but it also says to NOT place the sensor where there is going to be high temps or high back pressure. The area between the turbo and stock cat sees both of those.