Hello everyone,

Definetely need some suggestions on passing my emissions test. I have come so close but ended up failing. So heres my info
1992 Honda Civic DX
D16Z6 1.6L VTEC Engine
New spark plugs, O2 sensor, Oil, Air filter, Catalytic Converter

Got it tested twice today and gave the following numbers
1st Test

40 km/h
HC ppm Limit 75 Reading 79 FAIL
CO% 0.42 Limit Reading 0.32 PASS
NO ppm Limit 576 Reading 510 PASS

RPM 2312
Dilution 12.76

Curb Idle
HC ppm Limit 200 Reading 37 PASS
CO% Limit 1 Reading 0.04 PASS

RPM 1153
Dilution 11.53

So after I got it tested I drove it around a little more and got it tested again somewhere else. They let it sit for a good 10-15 min before it went in for testing.

2nd Test
40 km/h
HC ppm Limit 75 Reading 113 FAIL
CO% Limit 0.42 Reading 0.41 PASS
NO ppm Limit 576 Reading 705 FAIL

RPM 1651
Dilution 15.00

Curb Idle
HC ppm Limit 200 Reading 65 PASS
CO% Limit 1 Reading 0.06 PASS

RPM 1146
Dilution 13.35

Can anyone give me some suggestions on how I can make it pass?

 

First test:
The engine was running rich (high HC). I think replacing the distributor cap and rotor and then adjusting the ignition timing to spec would have solved the problem.

Second test:
The HC is still high (rich) but now the NO is also high. This suggests that running rich has now destroyed the cat.

 

Ditto.

 

ya there is no way its in fuel control is it throwing any codes ? what kind of o2 sensor did you put in it ? any mod's to the engine ?

 

No codes Denso O2 Sensor and No mods to engine

 

i would check your timing , and test sensor's like tps,ect,iat,knock or its possiable you ecu is bad