General engine questions/issues that aren't specific to the other categories
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By CaliEJ2
#71978 I failed my emissions test the other day because the NO.

the max that it can be at is 731, mine was 1342.

Any suggestions on what i can do?!?!?!!?
User avatar
By biretsu89
#72014 well .. we need a little bit of background info. How old is that cat? Does it need to be replaced. When was the last time it had a good tune up? (spark plugs, distributor, blah blah). I dont know what im talking about so...


http://www.civic-eg.com/viewtopic.php?t ... =emissions

There ya go... This guy knows what he is talking about... this should help out.
User avatar
By suspendedHatch
#72024 Most likely your base timing is off. Even if you've had the car "tuned up", often times if it's within spec they wont touch it. But there's a big difference in NOx output between 16 and 18 degrees. And if you are in fact at 16, try 14 and some 91 octane.

That or you could be running lean.

Once NOx get started they tend to go wild. It's like a slippery slope. It's not uncommon to see a Civic with over 3000 ppm, then make some small changes and bring it down to 500.

I'm a certified I/M tech btw.
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By OmarG
#72033 Where can I join the suspenedHatch fan club?






:lol:
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By CaliEJ2
#72040 i did a tune up right when i got it about 2 months ago. Oil change, oil filter, air filter, spark plugs and wires, disribuitor cap and rotor, water pump and radiator, new o2. I also want to change the fuel filter but idk, should I? When i got the results for the smog the timing was at 2 BTDC, i took it to the shop and set it right but not sure what its at. So i should run it on a higher octane?
User avatar
By suspendedHatch
#72331
CaliEJ2 wrote:i did a tune up right when i got it about 2 months ago. Oil change, oil filter, air filter, spark plugs and wires, disribuitor cap and rotor, water pump and radiator, new o2. I also want to change the fuel filter but idk, should I? When i got the results for the smog the timing was at 2 BTDC, i took it to the shop and set it right but not sure what its at. So i should run it on a higher octane?


Ignition timing at 2 BTDC?! That's not right. IDK if that's even possible unless you have the distributor on wrong. Timing should be 16 BTDC +/- 2 degrees on almost all Honda / Acura engines. Running overly retarded timing raises combustion temps.

What kind of spark plugs do you have? Pull one out and see how it looks.

If you've never replaced the fuel filter you should. Running lean can cause NOx.
User avatar
By suspendedHatch
#72332
OmarG wrote:Where can I join the suspenedHatch fan club?






:lol:


Sarcasm? I step on a lot of toes. Maybe yours?
User avatar
By CaliEJ2
#75300 i used seafoam about 6 days ago. i put it in the crankshaft, thru the brake booster vacuum hose and put some in my gas tank. of course i changed the oil, oil filter, and fuel filter. i havnt checked my spark plugs yet. About 20 days ago i went to the shop and they fixed my timing. when i went to go test it again it was at 25!!!!!! Whats going on!!??
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By CaliEJ2
#75302 ...i forgot to mention something else. my exhaust manifold is cracked i sealed it but theres still a minor leak. could this affect the NOx fail?
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By CaliEJ2
#76227 ????
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By biretsu89
#76256 No it wouldnt... the only thing it would do is make you fail the smog test because a crack in the exhaust mani is technically dangerous :lol: ..
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By CaliEJ2
#76347 since the catalytic converter is bolted onto the manifold i was told that the manifold cracked because the catalytic converter got clogged and then there was too much pressure so it cracked....is this true?
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By suspendedHatch
#76383 Most likely your manifold overheated. Rapidly heating and cooling will crack anything. Cat converters most often crumble apart and clog your muffler rather than melt internally and clog up.

But what's the point in asking? If the cat is right on the exhaust manifold pull it off and look inside.

Bad converter could explain your NOx.
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By CaliEJ2
#76387 what should i look for to know its bad?
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By suspendedHatch
#76519 Hold it up to a bright light and look through. You should barely be able to see out the other side. If a bunch of grayish crap pours out then scoop it back in and take it to a recycler. If it looks like lava inside take it to a recycler.

If the cat appears to be good perhaps just black inside and you have access to a blow torch blow it inside both ends of the cat converter and put it back on. Watch the pretty green and blue flames but don't burn yourself.