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DIY Lambda meter?
StevieB - 22/5/09 at 08:12 PM

Evening!

Is it possible to knock together a cheap contraption that will enable me to know (even roughly) what my lambda reading is?

One of my SVA fails was emissions, and it;s the only thing that I currently don't know is fixed (engine was running rough, but the carbs have had a thorough clean, balance and setup which may well have made the difference)

prawnabie - 22/5/09 at 08:15 PM

I did see an "electricians" diagram once on the net on how to build a series of leds that should you how lean or rich you are running with "stoich" in the middle. I will try and find it.

Only thing you had to buy was an 02 sensor really.

speedyxjs - 22/5/09 at 08:16 PM

Is it an exhaust gas analyzer you want? If someone may be able to lend you one? Id lend you mine if you were closer.

prawnabie - 22/5/09 at 08:17 PM

StevieB - 22/5/09 at 08:19 PM

quote:
Originally posted by prawnabie




Can't be all that hard though

StevieB - 22/5/09 at 08:24 PM

quote:
Originally posted by speedyxjs
Is it an exhaust gas analyzer you want? If someone may be able to lend you one? Id lend you mine if you were closer.


Doesn't that just measure CO? My CO and HC readings were well within the tolerance (I think, anyway), so it's just the lambda that I want to get right.

I know I could take it to an MOT station to test, but a) I'd like the chance to be able to mess about for as along as need to on my own time (and money) to get it right and b) I just like the idea of having another tool

prawnabie - 22/5/09 at 08:25 PM

quote:
Originally posted by StevieB
quote:
Originally posted by prawnabie




Can't be all that hard though


Its only a few drivers, leds and resistors on a pcb!!

RichardK - 22/5/09 at 08:40 PM

Have you got a lambda bung welded into your exhaust?

Cheers

Rich

StevieB - 22/5/09 at 08:44 PM

quote:
Originally posted by RichardK
Have you got a lambda bung welded into your exhaust?

Cheers

Rich


No, but it could be sorted if really necessary.

BenB - 22/5/09 at 08:53 PM

You can buy a cheap wideband lambda sensor / controller for £120-130. You could probably sell it on Ebay 2nd hand a few weeks later for 90% of that....

RichardK - 22/5/09 at 09:06 PM

I've got a jaw wideband that I can lend you on a, you bugger it, you replace it arrangement.

Let me know, but unfortuantly I'm away until Wed.

Cheers

Rich

MkIndy7 - 23/5/09 at 10:14 AM

Presuming you've already got the heater controller etc,

Wouldn't a Volt meter either Analogue or Digital be capable of showing the 0-5V signal it gives off, then either remember or mark on the analogue guage the required voltages or range.

MikeRJ - 23/5/09 at 02:05 PM

Don't bother with any of the narrow band AFR meters, they are less use than a chocolate teapot. At least you can eat the teapot...