supra33202

I have a 1993 S13 Hatchback with 240K miles.

The previous owner failed the smog check yesterday.

The result:

M1. 15MPH
HC: MAX 88 AVE 21 MEAS 28
CO(%): MAX 0.52 AVE 0.06 MEAS 0.08
NO(PPM): MAX 704 AVE 150 MEAS 775

M1. 25MPH
HC: MAX 53 AVE 13 MEAS 24
CO(%): MAX 0.50 AVE 0.05 MEAS 0.13
NO(PPM): MAX 738 AVE 136 MEAS 507

My friend help me to do the regular maintenance services after I brought the car.

We did:

Change engine oil and oil filter
Flush coolant and fill in 50/50 coolant
Clean fuel and change fuel filter
Replace air filter
fill up 91 Octane

I just smogged the car today and it failed.

M1. 15MPH
HC: MAX 88 AVE 21 MEAS 41
CO(%): MAX 0.52 AVE 0.06 MEAS 0.12
NO(PPM): MAX 704 AVE 150 MEAS 784

M1. 25MPH
HC: MAX 53 AVE 13 MEAS 31
CO(%): MAX 0.50 AVE 0.05 MEAS 0.10
NO(PPM): MAX 738 AVE 136 MEAS 432

How do I pass the NO(PPM) with 15mph? Any suggestion? Replace O2 sensor, catalytic converter?

Thanks!

ryguy

iTrader: (1)

NOx could be a faulty EGR.

supra33202

I will check the EGR after work. Actually, can you tell me more about EGR? Do I just replace a new EGR?

supra33202

http://www.autozone.com/az/cds/en_us...rInfoPages.htm

"The EGR valve diaphragm should lift up and down without restriction."

How does EGR valve diaphragm look like? Is it like a gold-colored, round-shape metal plate?

I checked last night, but I am not should how high will the valve diaphragm lift up?

http://img233.imageshack.us/my.php?i...img4583rf5.jpg
http://img80.imageshack.us/my.php?image=cimg4565vd7.jpg
http://img136.imageshack.us/my.php?i...img4562js3.jpg
http://img338.imageshack.us/my.php?i...img4570dk9.jpg

supra33202

2 days ago, when my friend and I were under car doing regular maintenance services, we saw the whole exhaust has rust and a red color. My friend told me that could be high temperature from somewhere in the engine. He remembered that his friend's new car has this red exhaust system problem, and they brought the car back to the dealer. And the dealer person told them that the cause of the red exhaust system problem is from high temperature from the engine or some sort.

If that is the case, what should I do?

I don't how old is the whole exhaust system. I think it is at least 5 years old because of the rust and stock looking.

Assuming, the previous owners never replace the exhaust system. I believe I should just replace the cat.

Would replacing the muffler help the emission?

Thanks!

supra33202

Do you think using seafoam would help passing smog check in my case?

http://forums.********.com/zerothread?id=126583&page=1

supra33202

THis is what we did last night:

1) We tried to remove the EGR valve entirely, but we don't know exactly how. Basically, we just removed the EGR valve vacuum hose and spray some Pryroil Carb&Choke Cleaner in it. We also sticked out finger in the bottom of the EGR valve and lift up the diaphragm while the engine is running. The engine stumbled, so we believe the EGR valve is working. Is there a easy way to remove the EGR valve from the car entirely? I want to clean the inside parts of the EGR valve. What nuts do I have to remove first? And what other parts do I have to remove first?

2) Then we seafoamed the car. We followed his steps:

33% gas tank, 33% crankcase. 33% intake manifold through brake booster line. I have a question here. Why the brake booster line will connect to the intake manifold? What is the purpose? And why there are other vacuum lines connect to the intake manifold?

http://forums.********.com/zerothread?id=126583&page=1

Compare with other cars on youtube, my car doesn't have alot of smog coming out from the exhaust. Do we need to pour one more bottle of Seaform? If we decided to pour 1/2 bottle to intake manifold and 1/2 bottle to gas tank, do we have to do oil change and change the oil filter again? My friend said we don't have to change the oil and oil filter, but I argued that the seafoam will make the engine oil thinning. So, changing the oil and oil filter is needed after each seafoam regardless where we pour into.

That is all we did.

3) "ok, do this, add a bottle of isopropyl alcohol to about a half filled gas tank, drive it around a bit to get it mixed and in the fuel line. alcohol lowers combustion temperatures thus NOx levels will be lower. also, nox resolved from running lean which is one of the symptoms. get the highest percent isopropyl alcohol and try again, get around 90% because the other 10 percent is water, though water is not combustable, it will dilute enough to not cause any harm. also, try retarding your timing a few degrees. that may help. these are just cheap/money free possibilities. the alcohol wont hurt your engine, just dont use more than 1 bottle..about 16 ounces

Let me know if this works for you. i bet it will. pm me or something"

Do you thing pouring alcohol in the gas tank will help emission?

Thanks!

supra33202

My car has 240K miles instead of 24K miles.

supra33202

1) Will high octane gas and octane booster help emission in my case?

2) Will retard ignition time help emission? How does it work? And how do I adjust the timing?

Thanks!

nk4e

What would always be good if you don't know what your doing is:
Buy the Chilton's Book for the Nissan 240sx
It helps alot, though I thought the usual lift points would be on the side but I guess I was wrong since I look for the rivets on the skirts. The Chilton's Auto repair and Diagnostic book is always helpful.

shrimpscampi

Just find a crooked smog guy...

RMS13FU

High NOx is the EGR.. or you are running lean.

Either way, it is caused but high combustion temps.

You need to find and download an FSM. There is a good chance your EGR valve could be fine, but the EGR solenoid or BPT valve could be wasted...