dare628

Hi everyone,

just picked up a 1993 22re for almost nothing expecting some issues with it. well took it to get smog check today, and it failed with flying colors.

Ive done some research on here and it seems like everyone has different issues depending on the results of the test's. Before I jump into buying a cat ($$) Im wondering if the following would help the truck pass?

so far I plan to do the normal routine of replacing

air filter - replace
plugs/wires cap/rotor - replace
02 sensor - replace
check adjust valve clearance
check timing

here are the results from the test below:

15mph - (rpm) 1577
(CO2 measured) 13.8 (O2 measured) 0.6
(HC PPM) max 95 (AVE) 38 (MEAS) 202 FAIL
(CO%) max 0.53 (AVE) 0.08 (MEAS) 1.23 FAIL
(NO PPM) max 552 (AVE) 97 (MEAS) 1416 FAIL

25mph - (rpm) 1711
(CO2 measured) 14.0 (O2) MEAS 0.7
(HC PPM) max 60 (AVE) 24 (MEAS) 171 FAIL
(CO%) max 0.63 (AVE) 0.09 (MEAS) 0.81 FAIL
(NO PPM) max 805 (AVE) 120 (MEAS) 1367 FAIL

From these results, it looks pretty much like a whole replacement of things, any direction on where to start would be great. Im not a toyota guy, just honda and datsun. Excited to have a little pick up to lug around stuff. thanks everyone.

Stevesk88

You'll probably pass with what you have on that list. But if you have the means to cut your cat out and put it back in properly I would cut it out and make sure it's not in chunks in there. Check overall condition and if its plugged bite the bullet and find an el cheapo universal to melt under it. If you really want you can pull it out and clean it with cat spray. Haha just my 2c

Terrys87

iTrader: (1)

What you have listed is a good start. I have heard that aftermarket headers can cause you to fail. The Plenum gets dirty from the EGR. I would give the whole intake system a cleaning. Here is some info on cleaning the EGR https://www.yotatech.com/forums/f199...l#post52146627 and the intake system and some on the next page. Just give it a glance to see what all is involved and how to tear it down and clean it. I don't have to deal with emissions but have gotten several EGRs working.

I would also do the Sea Foam Treatment as well when I had everything back together.

dare628

Thanks Terrys87/Stevesk88

I will post outcome, hopefully at the end of this, this will help someone else out.

Cheers.

Old_ blue

the high N0x kind of indicates that your EGR isn't working. take it out and clean it along with the passage behind the head. make sure you have vacuum to it and that you can open it with a vacuum pump. plugs, wires, intake and 02 will help with the smog definitively. you can also plug either the 1500 or 2500 exhaust readings in a lambda calculator to see if your running rich or lean.

dare628

Ok so here are some results.

Changed plugs out
Oil change
New denso o2 sensor
New cat

Passed.

Results now are
HC 3
CO 0.00
NO 2

Thanks everyone for your input and I hope this can help somebody else out!

Terrys87

iTrader: (1)

It is great when people post what helped fix their issues. It doesnt always happen and it will give the next guy some ideas of where to start. Luckily I dont have to deal with emissions. I know it can get costly if you dont know where to start or have someone else to fix it for you.