Thread: Air Fuel analysis for diesel (portable)

let me know when you find out... I've heard rumour control of some people having some sucess with smog counters

For those interested........

After a few phone calls to various diesel tuners, I have ended up grabbing this unit. Got the top notch one as can data log then record to a SD card, has multiple Input channels etc. Will be an asset when I tune the many after market forced induction vehicles + the duel chipped CRDS we have here.
Grabbed the venturi (Sniffer) and extension cable, also analogue inputs for the older set-ups as in my supercharged Rangie.

LM-2 Wideband O2 Digital Air/fuel Ratio Meter



wasn't cheap all kitted out, but then..... nor is a blown engine.

not to shoot you down but from what I've just read it doesnt deal with oxides of nitrogen or particulate matter which are the key killers for diesel emissions OR

are you just after it to monitor the O2 levels so you can tell when you're overfueling? If so... how are you going to get in Pre DPF where you can read the numbers? My assumption would be that you're going to drill and weld on a fitting then blank off?

This sounds like an interesting project. A wideband makes sense.I was surprised in your initial post

The wide band plug in O2 sensor type are no use for this.

As most major CRD manufacturers use wide band sensors for emmision control.
Here's the link to the one I had thought of although unsure of diesel tuning capability.
http://wbo2.com/3b1/default.htm
If I remember correctly the availability and price of some replacement sensors can be a problem. The above unit uses a freely available reasonably priced sensor.

not to shoot you down but from what I've just read it doesnt deal with oxides of nitrogen or particulate matter which are the key killers for diesel emissions OR

are you just after it to monitor the O2 levels so you can tell when you're overfueling? If so... how are you going to get in Pre DPF where you can read the numbers? My assumption would be that you're going to drill and weld on a fitting then blank off?

I guess tuning and emissions are two different things. EGR's in the bin.

Most petrol engines are tested post cat (unless tuning each cylinder, then its at each exhaust runner) so I don't understand why you would want to go pre DPF.

Yea, not what I originally was after, but after talking to some diesel tuners that use this exact set up I have relented.
Obviously running the wide band sensor in a venturi at the tail pipe is not as ideal as the bung pre cat. But does work as a benchmark. I'm more concerned about air fuel ratio than the elements for the max performance tuning. Off road only right.
Will be sticking a bung in my old 4BD1T, the CRD (Non Landy) and the Rangie. I'll venturi the others. Since it has duel sensor inputs, we can compare the differences.
The replacement sensors are around 80 bux by memory. Not that bad. They'll last for years as only be used for tuning and not run full time.

The unit does data log via sensor inputs when plugged in and records to the SD card. Comes with a program to run on the lap top so we can analyse the intire run.

I can already see the rail, MAP and MAF sensor input/out puts with the tuning software on the CRDs

This sounds more interesting all the time. With the chance of getting alot of useful information from it. Especially with the huge changes in diesel technology over the last 10 years and the differances in different refinements of injection control (Nissan, Mitsubushi).

Comparing the results from two sensors would answer some questions I have had. I know pre cat will show misfire (partial or full) where as post won't but I would of thought on a good running engine Lambda should be the same post and pre.

Keep us all posted.

the other thing to watch is the DPFs that do constant partial regen. They burn up oxygen in the process so you might get caught on that if you're relying on a post DPF sensor.

Originally Posted by Blknight.aus

the other thing to watch is the DPFs that do constant partial regen. They burn up oxygen in the process so you might get caught on that if you're relying on a post DPF sensor.

Even that would give some interesting figures regarding Lambda post and pre DPF.
I would guess it would be closer to 1 post DPF???...Maybe