BlackDB8

98 Honda Civic EX.. Not passing i'm real close but not close enough here are my numbers and suggestions on what i should replace and look at here are the numbers

15mph HC(PPM) Meas:72 Max 60 -- Failing
25mph HC(PPM) Meas 33 Max 43

15mph CO% Meas: 0.20 Max 0.53
25mph CO% Meas 0.16 Max0.51

15mph NO(PPM) Meas 222 Max 459
25Mph NO(PPM) Meas 78 Max 746


I'm only off by 12 which to me seems real close maybe not and suggestions and advice is appreciated

Former User

How old are the plugs, wires, cap, and rotor? Is the ignition timing set to spec? Engine running cold?

BlackDB8

Plugs were just done but wires haven't been replaced in awhile fuel filter and cap and rotor bout 8,000 miles ago buddy said might be my fuel pressure regulator since it passing at 25mph and not at 15mph? but what i'm reading its mainly my ignition is weak?

Weizhang115

Have you check your pcv that can be the cause some time. Timing should be ok unless the smog tech you other wise they have to check is part of he smog check

Ps also try some sea foam could hurt!!!!

Former User

Replace the plug wires and check the ignition timing.

BlackDB8

So i'm going nuts I've changed the plugs, wires, distributor, rotor, new oil, filter, and new pvc valve and I'm still failing the HC part of smog timing i'm being told is fine i cant check it myself what else should i do get at universal cat done at 300 bucks and pass? im slowly getting my bank milked please help

BlackDB8

I also ran some iso heet this time around if it counts my numbers were worse and failed both 15 and 25mph test not just the 15. At 15 mph there was a 2 point difference higher 25mph doubled from original 33 to 61 what about running some gtp additive and test again

Blacknight117

iTrader: (1)

Also check for leaky injectors. That's why mine kept failing.

BlackDB8

ok so my ignition timing is 13 BTDC which is off from what i'm reading is this my problem

TunerN00b

BlackDB8

bleh as much as i want to try the GTP stuff i dont want to fail again without any concrete info so tomorrow or monday ill be getting a new universal cat unless i come up with something

Former User

If the cat were bad, the NOx would also be high.

Is the engine running cold?

Any signs of an exhaust leak around the primary O2 sensor?

Is one of the fuel injectors stuck open?

Have you measured the fuel pressure and tested the FPR?

TunerN00b

You can always ask for a pre-test. They'll test the car normally, but the results are not submitted. Prevents a failure from being recorded in the system.

Yeah, you end up paying for 2 tests, but pre-test and if it passes immediately do the real test, and never have to worry about being flagged as "Gross polluter" or anything.

rhymeshark916

O2 sensor(s).