SMOG problems need help

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Jan 16, 2014
i have a 1987 fj 60, Im active duty marine in camp Pendleton California and smog test in California are frustrating. I got the test and here are the numbers at 15 mph
rpm 1557
%co2 meas 13.4
%02 meas 0.1
hc (ppm) max 125, gp 313, meas 170
CO% max 0.79, gp 2.09, meas 2.36,
no (ppm) max 1062, gp 2017, meas 124
I hope my format on these makes sense, if not please tell me a better way to do it, I know a good bit about mechanicing but I know nothing about smog. anything will help, I already tried searching this in thr forums and what I found out is its different for each truck and its smog test results.
Since your O2 levels are low and CO is high, that's often an indication of a malfunctioning air injection system. Aka smog pump and or the ACV assembly.

A workaround is to first make sure that your smog pump is working by pulling a hose and feeling for air discharge while engine is running.

If no air, or just a trickle, the smog pump needs to be rebuilt or swapped.

If the pump is pumping air, then the likely culprit is that ACV valve assembly that it connects to.


The workaround is to route a hose from the smog pump outlet on the pump directly to the bypass pipe running under the bracket holding the ACV. That pipe runs along the fender and leads to the exhaust pipe. Air normally gets pumped through it when you're driving over 50 mph...below smog test speeds.

Take a look and you'll see where it connects. When plumbed like that, the air will get pumped downstream of all the restrictions that contribute to restricting the flow, and instead will flow directly into the CAT.

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You are not that far off from passing, so get the air injection system working properly and you will probably be good to go. Also make sure that your air filter is not clogged.
thanks a lot for the help guys. its good to know its not far from passing. I will try these techniques and see. one more question for output shaft, when you say the workout is to reroute a hose from the airpump to the check valve, is that to test something, or to pass a smog test? on the diagram to me I looks like it routes the air completely around the smog pump. I would love a little more clarity on this technique.
thanks again.
If you know the air pump is pumping air, rerouted a hose from the outlet on the pump to the "pipe" end shown in the drawing below. Test it like that. Make sure everything looks normal. Unmolested. Hook it back up to normal after the test.


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