Just sharing something we were lucky enough to stumble upon recently.

It seems in CA they are changing the requirements for SMOG machines (I think they are going Wifi instead of the good old dial up they run on now for one thing, there may be other changes going on also)

Due to this, I have seen quite a few working SMOG machines coming up on the likes of Craigslist for very reasonable prices.

We bought this one from a shop in Oakland that had been using it until 2 days before we bought it



It was pretty grimy, so we set about it with some cleaner and spray paint, a new monitor and some vinyl graphics and it ended up looking like this :



This cost us the princely sum of $200. The guy we bought it from told us he bought it in 2004 and it cost $22k !! And that the new machine he had to get was $45K !!

So, for $200 we got a fully working 5 gas analyzer.

Some learning / info :

You often see these machines with gas cylinders on the bottom shelf. These gas cylinders are gases required for calibration. In normal use the machine needs calibrated every 3 days, otherwise it cannot be used to transmit legitimate SMOG results to DMV (Its "locked out" as it refers to in the manual) Now, you do not need to get these gases to use the machine. It will run just fine without them. It will just tell you its calibration is overdue and it's locked out from transmitting.

I decided to get these cylinders so I could do the calibration if I needed to. There are multiple online vendors who supply them. One such is partsqueen.com. The cost for the 3 calibration gases (zero gas, high gas and low gas), including shipping and hazardous handling fee came to around $200.

Our machine now passes calibration so should be within 5% of any other SMOG machine in the state.

I'm glad we got the gases because recently it failed calibration on NOX and we had to replace the NOX sensor. This is a consumable it seems and costs around $300 :-( There is also an O2 sensor which is a consumable for around $65.

One other thing to remember is for $200 we didn't get a dyno, so we just jack up the rear wheels of the car and drive it like that, having noted on a previous road test what RPMs we are doing at 15mph and 25mph. We then replicate these RPMs with the car jacked up.

All in all a very handy tool for your workshop!