NEED To Pass CA Smog, Please Help!

[StrnWolf]

So I looked at the vehicle record of my 95 SL2 and it has a TON of failed emissions tests. In fact it has 18 failed and 6 pass. At 156000 miles it got a new converter and passed then 22,000 miles later it failed. It is due for another test soon and I would like to know EVERY possible component that can affect my emissions test so I can test and deal with. I already have plans to replaced some parts which are:

ECTS
Air Intake Sensor (it has original sensor)
O2 Sensor
PCV Valve Grommet
PCV Valve
Air Filter
Spark Plugs
Spark Plug Wires
Gas Cap
TPS
All fuel/emissions hoses
Inspect Fuel Lines
Clean Injectors
Check and Clean IAC Valve if good, replace if bad
Check Fuel Pressure Regulator replace if bad

Other than CAT, injectors, MAP sensor, coils and ICM, what else would there be that can affect emissions?

[billr]

A new cat is probably the only thing you really need to do. My CA pre-inspection routine is to take compression, check/gap the plugs, check that IAT and ECT read reasonably, and make sure the cat is good. Obviously, make sure no codes are set, too. The newer "3-way" cats take care of most problems. Unfortunately, many cheaper cats are only good for short use, to pass a looming smog check. At 22K miles, your existing one may already be shot. And, if the engine has had running problems in the past, it could have killed even a quality cat.

[StrnWolf]

Originally Posted by billr

A new cat is probably the only thing you really need to do. My CA pre-inspection routine is to take compression, check/gap the plugs, check that IAT and ECT read reasonably, and make sure the cat is good. Obviously, make sure no codes are set, too. The newer "3-way" cats take care of most problems. Unfortunately, many cheaper cats are only good for short use, to pass a looming smog check. At 22K miles, your existing one may already be shot. And, if the engine has had running problems in the past, it could have killed even a quality cat.

So then I best just replace the CAT, since it was replaced there has been oil in the exhaust and the car has been running rich for THOUSANDS of miles. Is there any place I can get cheaper than RockAuto which charges about 220 to 240 for a CARB compliant one, or is that as cheap as they go?

[fdryer]

Unless error codes are posted, we're all in the dark. It's too easy to simply point and declare the engine and exhaust system as faulty............

[StrnWolf]

There are no codes and the current CAT is, according to vehicle records, 47,000 miles old. On the unrelated bright side I now know my mileage is accurate.

[RobertGary1]

You should be good to go. Just make sure all hoses etc are connected.

-Robert

[fdryer]

So what do you mean when you stated "... 95 SL2 and it has a TON of failed emissions tests. In fact it has 18 failed and 6 pass"? I don't know about anyone else on these forums, but I'm still in the dark as you're making two different statements without any facts. I'm not clairvoyant so my guess is I'm clueless. Perhaps others having clairvoyance can help you.

[StrnWolf]

Originally Posted by fdryer

So what do you mean when you stated "... 95 SL2 and it has a TON of failed emissions tests. In fact it has 18 failed and 6 pass"? I don't know about anyone else on these forums, but I'm still in the dark as you're making two different statements without any facts. I'm not clairvoyant so my guess is I'm clueless. Perhaps others having clairvoyance can help you.

I looked up service records and 18 emissions tests were failed and only 6 were passed in less than 9 years of records which covers from when the car had about 60,000 miles to when it had 184,000 miles. Right now it is at 198,000 miles. My first post shows what I will replace and check but I am wondering what else can affect emissions results. Right now the engine is running rich and I am due for smog and I want to pass the first time.

[pierrot]

Originally Posted by StrnWolf

...Right now the engine is running rich and I am due for smog and I want to pass the first time.

I accept your statement that the car is running with a rich fuel mixture condition. It would be helpful if you could tell us how you know this to be true.

As you're already aware, the condition you described can result in damage to the catalytic converter. BTW, do you have to take your car to a "Test Only" smog station this year?

[StrnWolf]

Originally Posted by pierrot

I accept your statement that the car is running with a rich fuel mixture condition. It would be helpful if you could tell us how you know this to be true.

As you're already aware, the condition you described can result in damage to the catalytic converter. BTW, do you have to take your car to a "Test Only" smog station this year?

As always with my two Saturns they both MUST only go to a Star-Certified Test-Only station. As for Running rich the spark plugs only have about 9,000 miles on them and when I did a compression test the spark plugs showed theres too much fuel in chambers. Also the exhaust smells strong of fuel.

[billr]

Does anybody think live-data could help this OP? I have an old Snap-On scanner that will read live-data in this OBD1 Saturn, and live close enough for it to be a possibility...

[fdryer]

Let this thread die instead of maintaining the same two threads.

billr, using an scanner can't hurt as you're most likely in the only position closer to the OP than anyone here. What hasn't been posted are copies of the emissions report that doesn't seem to be important enough to share so anyone following these threads can have an idea of what failed........... Your questioning whether or not the correct coolant sensor seems to be the only best guess along with rich fuel mixtures.

[Integral]

Originally Posted by StrnWolf

So I looked at the vehicle record of my 95 SL2 and it has a TON of failed emissions tests.

I experienced a very similar situation earlier this year.

See my thread: CA Failed Smog on Low Speed Test Only

This is what worked for me, your situation may be different.

The Cliff Notes Version:

1. Normal maintenance stuff:

Change;

oil and filter
air filter
change plugs

Clean;

throttle body
PCV
air intake

2. Fix

Find and fix any and all exhaust leaks. OldNuc has simple and effective method for finding exhaust leaks listed on my thread. Pay close attention to the flange. If there is a leak there make sure to clean the rust off of both mating surfaces, otherwise the leak my persist.

Replaced the old O2 sensor

3. Hack

Use a mixture of E85 (ethanol) and regular unleaded (87) to reduce the HC. A 60/40 mix worked for me.

Replace the IAT sensor with a 270 ohm resistor. Carefully snap the tip of the IAT sensor off and solder the resistor to the two wires (method courtesy of OldNuc and fdryer).


Good Luck. Please post the before and after of the smog results.

[StrnWolf]

Originally Posted by Integral

I experienced a very similar situation earlier this year.

See my thread: CA Failed Smog on Low Speed Test Only

This is what worked for me, your situation may be different.

The Cliff Notes Version:

1. Normal maintenance stuff:

Change;

oil and filter
air filter
change plugs

Clean;

throttle body
PCV
air intake

2. Fix

Find and fix any and all exhaust leaks. OldNuc has simple and effective method for finding exhaust leaks listed on my thread. Pay close attention to the flange. If there is a leak there make sure to clean the rust off of both mating surfaces, otherwise the leak my persist.

Replaced the old O2 sensor

3. Hack

Use a mixture of E85 (ethanol) and regular unleaded (87) to reduce the HC. A 60/40 mix worked for me.

Replace the IAT sensor with a 270 ohm resistor. Carefully snap the tip of the IAT sensor off and solder the resistor to the two wires (method courtesy of OldNuc and fdryer).


Good Luck. Please post the before and after of the smog results.

So the special fuel mixture and the modified IAT will increase chances of passing smog?

[Saturn Night]

Originally Posted by StrnWolf

So I looked at the vehicle record of my 95 SL2 and it has a TON of failed emissions tests. In fact it has 18 failed and 6 pass. At 156000 miles it got a new converter and passed then 22,000 miles later it failed. It is due for another test soon and I would like to know EVERY possible component that can affect my emissions test so I can test and deal with. I already have plans to replaced some parts which are:

ECTS
Air Intake Sensor (it has original sensor)
O2 Sensor
PCV Valve Grommet
PCV Valve
Air Filter
Spark Plugs
Spark Plug Wires
Gas Cap
TPS
All fuel/emissions hoses
Inspect Fuel Lines
Clean Injectors
Check and Clean IAC Valve if good, replace if bad
Check Fuel Pressure Regulator replace if bad

Other than CAT, injectors, MAP sensor, coils and ICM, what else would there be that can affect emissions?

1995 emissions standards were way less stringent than 2018/2019 California PPM level thresholds.

Replacing all of that is likely still going to fail, because the OBD-I system was programmed to conform to either Federal(less stringent) or 1995 levels of emissions.

From my understanding, California requires ANY vehicle to pass emissions based on Current thresholds for the 2018 model year specifications.

I am going to recommend running premium fuel, which will reduce NOx emissions at 2,500(or 2,000rpm, as I can't remember which rpm range they simulate driving).

As far as HS emissions, you are probably going to be pretty high, as Saturn engines tend to run a tad on the rich side with factory programming.

Hotter plugs may help with low-speed burning, which will reduce HS emissions(but will INCREASE NOx from increased combustion temps). This is why I recommend premium fuel, preferably Ethanol-Free, as ethanol blended fuels run richer than EFP fuel does, due to less energy density per molecule.

[Integral]

Originally Posted by StrnWolf

So the special fuel mixture and the modified IAT will increase chances of passing smog?

Yes, in my case that was the difference between just failing and just passing.

But it was the combination of all the things I did that took it from a badly fail to a just pass. The largest contributor was most likely fixing the exhaust leaks.