Wideband O2 sensor

[Bitsyncmaster]

I did have a post on using the wideband in my DeLorean but I guess it was on the old crashed site.

When you buy a wideband unit it consists of the wideband sensor and an electronic unit to drive the sensor and provide an output. The unit I have is an LC-1.

http://www.innovatemotorsports.com/products/lc1.php

You program the LC-1 via a USB to RS-232 cable driver. The LC-1 has two analog outputs so you can program them to simulate what the narrow band sensor outputs (0 to 1 volt). I have one output programmed to output 0.5 volts at 14.7 AFR and the other output to output 0.5 volts at 13.0 AFR. I built a switch to drive one of those outputs into the normal one wire (signal) and ground inputs into the stock lambda ECU.

I also built a little circuit that takes the LC-1 LED fail code output to drive my stock dash LAMBDA light. So when you put the key on, my LAMBDA light will flash for about 15 seconds until the LC-1 has warmed up the sensor and is running closed loop.

The wideband sensor replaces the original narrow band sensor in the same bung. But that wideband sensor has a very large connector on the end of the cable so you can not run the wiring like the OEM setup unless you remove the connector. You can not pull the connector pins so I cut the wires and installed small pins that crimp onto the wires. You cannot solder onto those sensor wires. I think the wires are nickle plated.

I will look for some old photos to help if you want to do the same.

[dustybarn]

I can personally vouch for the LC-1. I have one, driving a dashboard A/F gauge (my car has the intake system from a Renault Alpine GTA, and it was invaluable for jetting the carburetors).

The LC-1 is VERY sensitive to ground noise. I found it was flaky until I ran a dedicated grounding wire that connects directly to one of the valve cover bolts, YMMV.

[Bitsyncmaster]

I see Innovate now has an LC-2 but that unit now incorporates an internal LED to show you status. I use that status signal (comes out on the LC-1) for my dash light status.

I could not find the photos I had posted on the old .com forum (late 2009). I must have saved them on my work computer which I don't have access to anymore.

[FABombjoy]

Another LC1 user here since 2008. I've experimented with tweaking K-Jet over the years and it's been very helpful in determining the results of each test.

[dmc6960]

I've had dismal luck with my LC-1. Unit works fine for a few weeks then just quits throwing error 8. Went through 4 O2 sensors, countless firmware updates and back revs, and even splurged for their fancy heat sink. Nothing would keep the sensor working for more than a few weeks.

After the second sensor quit I installed Dave's modification to hook up the unit to the Lambda light. Works well, to inform me of impending DOOM for the O2 sensor! :frantic:

Had been considering getting a different brand of wideband O2, but fool me twice; I saw the new version, LC-2 and bought it. Lots of other people do have good luck with their LC-1s, so I'm going on faith here that I just got a genuinely bunk unit.

I'm going to miss having the diag light readout in the dash since its built in to the unit now. Perhaps I'll build a little circuit to at least light up the LAMBDA when output 2 goes high imp.

This year may finally be the year I finish EFI tuning.

[Josh]

My LC-2 has been great. I will admit I am on my second one, but I fried the first with a flakely power connection (which was so bad it fried my Megasquirt).

[Bitsyncmaster]

My LC-1 just uses the power and ground tapped off the lambda ECU wires. I think only one time I saw an error code flash but turning the car off and on again cleared it. I'm still using the same sensor when the unit was first installed. I have stock exhaust.

You must remember not to ever run the engine without the LC-1 powered if your doing any work on your car. With it hard wired like I have it can't be turned off anyway.

[Horsebox]

This is genius.

If I've understood it right, at the flick of a switch, the stock lambda system targets 13:1 AFR as opposed to 14.7:1?

Do you notice a difference in the way it drives?

[Bitsyncmaster]

This is genius.

If I've understood it right, at the flick of a switch, the stock lambda system targets 13:1 AFR as opposed to 14.7:1?

Do you notice a difference in the way it drives?

I'm not an aggressive driver so don't feel much difference. I'm sure a run at the track or dyno would show better performance. You could probably do the same if you put a switch on your wide open throttle switch wires but that is not a closed loop AFR control.

Yes you drive the wideband output into the stock lambda ECU.

[Bitsyncmaster]

I lost the photos I took when I did the wideband install. But here are some of the switch I built to select which of the two outputs to drive into the lambda ECU. I guess you could just use a double pole switch to select which output but I used an SPST switch so made the analog driver board.

The first photo is me testing the AFR reading the tailpipe with an LM1 wideband unit. I can get the same reading that way because I have a gutted CAT. The LM1 has more inputs if you want to do on road testing but even the LC1 can output on road testing connected to a lap top.

[Josh]

I wired mine up with a simple relay.
It is worth noting I am running a gm obd2 computer but the concept is the same.
I have the stock 02 sensor hooked into the computer. However when 12v is applied to the relay (hooked in through my cruise control switch) it flips over to the wideband 02. I have the wideband 02 setup on the narrowband output, and it bounces from 15.5 - 16.5 AFR. I have been able to pick up 3 mpg on the highway as a result.

[Delorean Industries]

I wired mine up with a simple relay.
It is worth noting I am running a gm obd2 computer but the concept is the same.
I have the stock 02 sensor hooked into the computer. However when 12v is applied to the relay (hooked in through my cruise control switch) it flips over to the wideband 02. I have the wideband 02 setup on the narrowband output, and it bounces from 15.5 - 16.5 AFR. I have been able to pick up 3 mpg on the highway as a result.

Get ahold of me when you have a moment josh. I have something I think you would be interested in to further this project.

[Bitsyncmaster]

I wired mine up with a simple relay.
It is worth noting I am running a gm obd2 computer but the concept is the same.
I have the stock 02 sensor hooked into the computer. However when 12v is applied to the relay (hooked in through my cruise control switch) it flips over to the wideband 02. I have the wideband 02 setup on the narrowband output, and it bounces from 15.5 - 16.5 AFR. I have been able to pick up 3 mpg on the highway as a result.

I ran a little time with those high AFRs on my PRV but it just did not have enough power on hills in high gear.

[DMCVegas]

I ran a little time with those high AFRs on my PRV but it just did not have enough power on hills in high gear.

Is it just when running lean that you have a loss of power on the hills?

[Bitsyncmaster]

Is it just when running lean that you have a loss of power on the hills?

Yes, only noticed that as the problem running 15.5 AFR. I did not run it enough to see if the mileage got better. But you would need to down shift on a hill that normally I could stay in high gear with. My car running at 14.7 AFR seems to have plenty of power on most hills as long as your going above 50 MPH.

[Josh]

I ran a little time with those high AFRs on my PRV but it just did not have enough power on hills in high gear.

Thats were EFI comes in... You can run these PRVs very lean, very forgiving with the low compression. On my 3.0 I had a cruise afr of 17.0

[DMCVegas]

Thats were EFI comes in... You can run these PRVs very lean, very forgiving with the low compression. On my 3.0 I had a cruise afr of 17.0

But the the Eagle Premier does in fact have a higher compression ratio as well as displacement. If memory serves, a stock DMC-12 PRV is 2.8L running @ 8.8:1 compression, whereas the Eagle Premier is a 3.0L running @ 9.3:1

That's also not accounting for the more free-flowing cylinder heads, nor the massive variations in even just stock exhaust manifolds. Or the split-crank journals that switch over to even-fire. With all due respect, I would absolutely believe that you would have higher power outputs (along with NOx emissions), but that also comes to fruition by the other massive design changes which that engine benefits from, and not solely from just a change in a fuel delivery method.