Mongo

I took my car out for a little run this weekend and noticed something different this time around on WOT. Usually at WOT, I only have one light lit and that is the blue before the last one on the gauge. From what I have read, this is a normal reading at WOT.

Yesterday after a couple of WOT runs, I noticed that I had 4 lights illuminated this time. They were the same lights on all 4 WOT runs I did. The gauge read 1 yellow, 2 green and one blue with an occasional oscillation to 5 lights. The last light being a dim lit yellow. I didn't notice any power loss or missing on acceleration. I do have a slightly lumpy idle every now and then, but that is only on the first 15-20 seconds of a hot start which then settles smooth..

I know these gauges aren't 100% accurate and I bought it to see what was going on when I was having my LH problems. I am just curious if this thing is telling the truth and I am running a little lean on WOT now or if those 4-5 lights illuminated could be a fluke. These things read O2 sensor voltage apparently.

Below is the narrowband gauge I am using. I don't usually take my car out much anymore; twice a week at most now on the weekends usually and I get it up to operating temperature through mixed freeway and street driving. It may just need an old school Italian tuneup.

dprantl

You answered your own question. You really can't tell what is going on with the AFR accurately enough using that measuring device. Only a wideband O2 will tell you if you are getting dangerously lean or not at WOT. If I had to guess though, you are probably fine. You are not close to "Ideal" which is 14.7:1. As long as you are at 13:1 it is good. In fact, stock S4's tend to run very (too) rich at WOT in the upper RPM ranges.

Dan
'91 928GT S/C 475hp/460lb.ft

Mongo

Yes I am dying to upgrade to wideband so I can see in real time what it is rather than see something twinkle like Christmas lights when the car is at idle between lean and rich. With all those lights illuminuated, I am sure it is around the normal range. Thanks for the reply

dprantl

Why wait, just do it. It doesn't cost that much and really is easy to install. You don't even need an extra exhaust bung if you use nbO2 emulation.

Dan
'91 928GT S/C 475hp/460lb.ft

123quattro

What Dan said. Buy a wideband. That narrow band gauge will tell you nothing useful. Just rich, stoich, or lean.

AO

I thought I had posted to this thread yesterday, but maybe forgot to hit "submit"

What I had said is exactly what the others have said in that the NB gauge will only tell you grossly if your Lean, Rich or Stoich. You cannot tell with any kind of accuracy if your at 15.0 or 15.5.

If you're concerned, you need to have a WB. You can get on with a gauge for less than $200 these days which is a real bargain.

Good luck.

Cosmo Kramer

Mongo, this is the WB I am running. Under $200 shipped and works very well. The plug is a bit big so it is a tight squeeze going through the hole in the tunnel but it can be done.

http://www.enjukuracing.com/gaugetyp...er-p-7000.html

Mongo

Dan - I have heard that NBO emulation may conflict with the LH by delaying the time to send the signal from the O2 to it. AEM has emulation but I have not heard about any experiences with it. I have heard bad things about the Innovate ones.

PorKen

Colin says the new Innovate digital gauge sensor wiring easily fits right through the O2 hole. It has dual analog outputs like the LC-1. $199.

http://www.innovatemotorsports.com/products/MTXL.php

123quattro

AEM are better quality than Innovative. Both are much better than not knowing though.

dprantl

I have used nbO2 emulation on my TechEdge 2J1 and it has worked just fine for 1.5 years. I also passed an emissions test with the car in that configuration.

Dan
'91 928GT S/C 475hp/460lb.ft

Mongo

Good to know. I have a couple of items on the grocery list for when my tax refund arrives. Leftovers will be allocated for WBO now after hearing emulation works plenty fine.

Z

There were some problems with the narrow band emulation of the very early Innovates because their response speed was too fast for the ECUs in some cars. Since then, Innovate added the ability to change the response speed that's output to the car's ECU.

Mongo

Funny, I was just reading their manual for the MTX-L and saw that in there. I wonder what the response speed is for the LH?

Mongo

Oh and just out of curiousity, where are you guys running these WBO setups getting your 12 volts from? The O2 heater plug and O2 ground connections?