ted_dejong

Hey, I just went for Emissions testing today. Drove around for about 15 minutes before I got it tested. Im from Ontario and I have a 92 Honda Civic DX Hatchback with a D16Z6 Engine. I recently installed a new O2 sensor. My car has an aftermarket exhaust system with a catalytic converter and headers. Anyways I had my emissions test today and basically failed on all levels. Any suggestions on what I should do to pass. Here are my readings

At 40 km/h
HC ppm Limit 82 READING 132 FAIL
CO% Limit 0.45 READING 1.12 FAIL
NO ppm Limit 0636 READING 1215 FAIL

RPM 2469 VALID
Dilution 15.19 VALID

Curb Idle
HC ppm Limit 200 READING 219 FAIL
CO% Limit 1 READING 1.78 FAIL

RPM 1152 VALID
Dilution 14.86 VALID

Former User

When both HC and NO are high, it's a sign that the cat is bad, which almost surely happened due to the engine running rich.

Is the engine running hot/overheating? Is it running cold?

When was the last tune up (plugs/wires/cap/rotor)? Is the ignition timing set to spec?

ted_dejong

Car does run pretty hot but never overheats or runs cold. Plugs/wires/cap/rotor were all changed when I swapped the motor into my car almost 2 years ago. I believe ignition timing is set to spec. Is this when you check the timing belt with a timing gun? If not please inform me how I can check the ignition timing. Also if my car is running rich how would I go about correcting it? I will for sure be changing out the plugs / cap / rotor before I retest it. Thanks again your help is much appreciated

Former User

This will increase NO emissions so fix this problem. Have you replaced the thermostat? Is the head gasket blown?

You might benefit from replacing the spark plugs (NGK only) and inspecting/cleaning the contact points on the cap and rotor.

You are mixing up mechanical versus ignition timing. The FAQs sticky has a diagram that describes how to check/adjust the ignition timing. This is done after you do a tune up.

Start with what I mentioned above.

Any CEL codes?

ted_dejong

My engine light isnt on. I dont have a code reader but when I use the paper clip/ wire method to the connector I dont get any codes. The thermostat is a couple of months old and I dont believe the head gasket is blown although I am not entirely sure how to check this. The car seems to drive fine to me.

Former User

You can't use a code reader for your OBDI car. Does the CEL work? If there are no codes, the CEL should turn on and then off after 2 seconds when the key is turned from off to ON(II).

Describe why you think your engine is running hot. At full operating temperature, the temp gauge in the cluster should read below the halfway mark.

ted_dejong

Yes, when I start my car the CEL goes on for 2 seconds then shuts off.

I feel the engine is running hot because after driving it if i directly touch the valve cover it is hot to the hand. Never does the temperature gauge on the cluster pass the halfway mark, if anything when the engine is fully heated it sits just below the halfway mark.

Former User

The CEL and engine temperature are fine.

Focus on the tune up and ignition timing. Afterwards, if the improvement in HC and NO levels is still not enough to pass emissions, then the cat may be dead and need to be replaced.

ted_dejong

Alright, Thank you for your suggestions. I will definetely take your advice. Any thoughts about running seafoam ? How about the guaranteed to pass additive?

Former User

Couldn't hurt and might help. If you decide to do a Seafoam treatment, though, do it before you replace the spark plugs. Otherwise, you will foul the new plugs.

Forget additives that make empty promises or provide short term effects. Sticking with the basics is always the way to go.