Ca. Smog/machine rpm pick up problem
 

I am in Ca. and am trying to get a pretest. My system, wires are new and there is no problem with the engine. The guy said he could not get the rpm to read correctly as he throttled up on the machine. My thoughts are he may be inputing the TAS smog machine incorrectly and or just using the incorrect set of plugs. I am going back next week and need some input if there's anyone who has run into this before. Thanks

I feel for you on the smog thing its sucks. call tri point they know a guy who can test a rotary right they won't do anything illegal but will give you a fair test .

They are screwing up somewhere. Back when my car was completely stock, a technician who didn't know a rotary from a lawnmower was able to get my test done without a problem.

Might want to post this on the west forum also.

i just got a pre-test yesterday (i failed!), and at first the guy couldn't get an rpm reading also. he left that rpm sensor (which i was told works by sensing the magnetic field created by the spark plugs) on the windshield. he then popped open the hood and put it somewhere else in the engine bay, i didn't get to see. being that the motor is mounted much lower in the 7, that might be why. hope this helps

I had the same problem when I lived out in San Jose. They had a hell of a time getting a timing signal off the plugs due to the trailing plugs also generating a magnetic pulse. If I remember right he found the just the right place to put the engine bay but he didn't actually attach it to one of the plug wires.

I have to hook the timing signal up every time. They always screw around for 15 mins trying to make it work and then I have to walk out there and do it...

Same RPM reading pickup problem with the smog station
 

I would greatly appreciate any insight on where to exactly place the smog check tachometer pickup in my 1986 Mazda rotary engine, so I could help get the smog tech unstuck! Thanks!

Assuming they have the pickup that clamps around a spark plug wire, I think it would probably go one one of the trailing spark plug wires. Those will fire once every 360 degrees, which is the same as a 1980s or 1990s engine with wasted spark. Similar settings as they might use for a 1990 Miata or 1990 Eclipse.

The main challenge is spark plugs make a lot of electrical noise, and there are other spark plug wires nearby making noise that can interfere with the signal they want to read. Plus I'm sure their clamping pickup is old and doesn't get used much anymore. Most cars on the road in California are new enough that the technician plugs into the OBD2 diagnostic port and trusts whatever data it's receiving from the factory ECU.