Help - Search - Members - Calendar
Full Version: O2 sensors
914World.com > The 914 Forums > 914World Garage
sunfloweryellow914
Regardless of fuel delivery system, wouldn't it be nice to have four O2 sensors, and 4 little guages that you could see in the cab? Seems like a reasonable request. Anyone ever seen a setup like that?
cnavarro
I think that a quad EGT gauge and its respective senders would be cheaper, and just as informative.

Charles Navarro
LN Engineering
http://www.LNengineering.com
Aircooled Precision Performance
ChrisFoley
agree.gif
DNHunt
To get any good info from them they have to be Wide band O2 sensors. These are expensive and pretty complicated. I have one with my fuel injection system and I've killed 2 in a year. Fortunately they're on a warranty but, the guy won't keep giving me new ones forever. Our exhaust streams are tough environments for sensors since we run pretty darn rich. A simple probe seems like a better solution.

Dave
kdfoust
I'm planning to buy this wide band setup for tuning my car when the engine goes back in a month or so.

Dave, what are you using?
Andyrew
Im using that innovate unit. Works like a charm so far.. A little trouble clearing the log, but I think thats computer related, not LM1 related.

Andrew
Brad Roberts
I was approached by a Lockheed engineer to help him develop a fuel injection system that measures cylinder pressure to determine the amount of fuel needed.

He also has a silica based suspension system that he is testing for the 911's and 914's. It is very similar to what the Mercedes and Corvettes now use. Basically it is active suspension with variable rate shocks/springs done with electronics. He uses a G sensor to detemine what the car is doing and whether or not the car needs more or less shock/spring on any given corner.


Should be fun testing.


B
airsix
QUOTE(DNHunt @ Mar 24 2004, 06:51 PM)
These are expensive and pretty complicated. I have one with my fuel injection system and I've killed 2 in a year.

YIKES! Dave, please give details. Which sensor model/brand? Are you running it full-time or is it only in the car during tuning runs?

-Ben M. (minutes away from buying a WB setup)
SLITS
Why not an EGT for each cylinder - much cheaper, mechanical and reasonably reliable.
DNHunt
Ben

I've been running it full time closed loop with a variable AFR target linked to load. The first one lasted about 3 months. The last one just died. I'm using the NTK L1H1 sensor with the DIY-WB controller. THere's a few of possibilities for the failures. 1) the heater circuit is bad and it is heating too fast. (last check this seemed fine) 2) the exhaust stream is very dirty and the sensor dies (this is my favorite) 3) the board is bad.

Good news is the engine runs fine open loop

I plan to use this to tune my new engine to tune but I'm gonna run open loop and plug the bung.

Dave
mightyohm
The wideband O2 sensors don't like to be mounted close to the head end of the exhaust system. They need to be able to use their internal heater to heat up HOTTER than the exhaust gasses they are measuring. So if you had 4 of them you'd have to mount all 4 pretty far downstream, like at the ends of the heat exchangers. Even there might not be far enough? Not sure.

With the cheapest WBO2 kits, 4 sensors and 4 meters will run you about $700.
phantom914
QUOTE(DNHunt @ Mar 24 2004, 06:51 PM)
These are expensive and pretty complicated. I have one with my fuel injection system and I've killed 2 in a year. Fortunately they're on a warranty but, the guy won't keep giving me new ones forever.
Dave

DNHunt,

Who did you buy your sensors from that replaces them for you and how much were they? I had nightmares trying to buy one from a place on the web called The Parts Bin and ended up getting one from Autozone for about $180


Andrew
mightyohm
$180???


GEEZ!!! Get a wideband kit that uses the LSU4 sensor. They are $25 ea.!
DNHunt
Bosch LSU4 is the way to go. UMS will use these and when I build anothe brain I'll pick that.

I get the NTK sensors used from a Honda wrecking yard. They come out of the lean burn Civics. It was the only choice a year ago and its nice to see the AFR readings on the laptop screen when you are tuning.

Dave
mightyohm
The kit I built uses the LSU4. It's the Tech Edge kit.

Disclaimer: I have yet to install it on my car. But it seems to work. Hopefully it will go in within the next few weeks.
SpecialK
Here ya go!


http://www.buckeyetriumphs.org/technical/C...r/AFMonitor.htm

Still waiting on my LM3914's to arrive (4) -

Gonna mount it in my console right next to my (yet to be purchased) Quad EGT Gauge mueba.gif
lapuwali
Special, that's for narrowband sensors, which are cheap and easy to make meters for (simple voltmeter). The wideband sensors require much more elaborate electronics (although they're still not that big a deal). Look up DIY-WB or WB 02. There are a few schematics and diagrams for the wideband electronics.

For the money, the Innovate gadget is just about the best thing, unless you really want to build one yourself, or you really want to have multiples of them.
TimT
The narrow band sensor just gives a YES/NO air fuel reading

Either its to rich or to lean... it doesnt tell you to what degree its rich or lean.

Look at the graph

a near vertical line at Stoi..

Stoi is good for emissions and the enviroment, but its not the most powerful air fuel ratio

Lambda graph
TimT
now the power graph
TimT
We like Power, with a narrow band sensor you cant target a/f's with any degree of certainty...

I built a tech edge wideband to replace my beat to crap FJO, Id just buy the innovate a/f instead of building my own

BTW I got the LSU4 for 29.99

on app is a 2001 VW golf
This is a "lo-fi" version of our main content. To view the full version with more information, formatting and images, please click here.
Invision Power Board © 2001-2024 Invision Power Services, Inc.