91 CRX SI

I have a question. i have been trying to get my car smog for the past couple of mouths now here in California. And my question is if the smog test papers say 1.5 liter engine but my engine is a 1.6 liter will this keep me from passing. The reason I keep failing is because of high nox. I know my car does not have an egr valve but I think the 1.5 liter engine does. If the tech put the right engine would my MAX nox go up? I have attached all three tests to this post. Just to give you an idea of what I have changed to the engine to try and get it to pass.

Catalyst convertor
Spark plugs
Wires
Rotor
Cap
Oil
O/2 sensor
PCV valve
HEADERS (now have the stock headers)
Air intake (now has the stock air intake)
Timing to 16 degrees
Change thermostat.
Flush radiator and Change radiator hoses.
Fuel filter.
Sea form the engine a couple of times. And change the oil
I tested the vacuum lines no leaks.
did compression test it past
Smog with 91 octane and drove car for half an hour before test.


So again my question is. if i tell the tech that my engine is a 1.6 liter and not a 1.5 will this help me pass the smog test. And if there is anything else i can do to my engine to help it pass would be appreciated

 

I looked at the max allowable on my test and I have

Nox @15 846ppm
Nox @25 746ppm for the 1.6 in my 88 crx si

So actually the 1.5 has higher allowed max's

You have alot of O2 left over. These numbers should be 0.2 - 0.4 at 15
and at 25 they should be almost 0.0 or 0.1.

The cat uses O2 to break down the other elements.

Your cat either is not very efficient, or your A/F is not fluxuating for the cat to use the O2, or you have a exhaust leak. Check the exhaust manifold carefully for cracks also. Any leak before the cat is bad news.

I suggest you run lower octane as it burns cooler which will lower combustion temps thus lowering Nox.

Is your timing spec 16 or 18btdc? You have room to retard 2 degrees from spec. This will lower Nox abit too. Don't go pass 2 degrees or it is a fail for timing.

 

Do you have a stock muffler/pipping on there?
Did you ever upgraded the fuel pump?
was there a check engine sign for anything before?
when u installed the headers and anything with the exhaust did you properly put a gasket or flange where its supposed to be?

 

go to store and buy HEAT. I think it is guarantee you to pass.

 

alright guys i passed smog, nox went all the way down to 136(15mph) and 63(25mph) from 2000 something.

what i did i ended up doing anther seafoam but this time to clean the carbon out of the top of the pistons that what i think was in there from a valve cover leak when i took the spark plugs out the oil dripped down(long time ago about two years). anyways i put cap full of sea form in each piston(about 2oz) with the spark plug out let it sit(about 15min) then turn the engine over with the spark plugs out to push the stuff out. after i did this i put 1/3 of the stuff thought the vacuum line with the engine running. drove the car for 25min and did this two more times. i then took anther 1/2 bottle of the stuff and ran it thought the fuel line and then put the rest in the oil crack case. ran the car then change the oil. i also found i had a hole before the cat in the down pipe not to big smaller than 1/3 the size of the dime so i welded it. went to the smog place and i knew i passed becuase the computer wasn't sniffing to long.

ive notice after the seafoam my car responds alot better now.

timing was set back to 18 from 16.

i also told the smog guy to change my engine to 1.6 becuase he was showing it as a 1.5


i have attached the picture of the results.

thank you all for your reply's.

 

It's funny how we learn that after the first few smog tests.
The longer it takes = FAIL, the faster = PASS.