Hey guys. So, I just went to smog station today to get my car tested for registration and it failed. Just by 5 points of HC(PPM) Here's the result.



Here are the things I did before I went there.

- Tune up-Oil change
-Seafoam treatment to clean the intake/exhaust system
-Cleaned the fuel cap.
-Drove around for at least 1 hour on highway.

I had to go to the STAR station because DMV required me to get it tested there. As you can see, it failed by just 5 points of HC. The guy who did the test said I should replace the CAT. Is that the problem? The other guy who was at the counter said I should do the tune up again and change the timing to 10 BTDC. I don't know who to believe. So, please help.

If I posted in wrong thread, I'm sorry in advanced.

Here's the specs of my car.

This is 95 DX trim.
-D16Y8 engine
- manual transmission
- auto Y8 mani modded to work with manual. (drilled 3 IACV holes)
- GSR TB (FITV bypassed considering Y8 OEM setup doesn't require FITV. Coolant line from engine directly to IACV. FITV is closed with custom gasket)
- OBD1 stock ECU
- OBD2 distributor
- AEM cold air intake
- IAT drilled on intake. Not on mani.
- Stock Exhaust Manifold.

 

try cleaning out your throttle body and seafoam in the gas for a tank or so then try

 

Yeah. I did that before I did seafoam. I haven't done seafoam in the gas tank. Would that help if I did? I also forgot to mention that my fuel was almost empty when I did the test. Would that matter?

 

a buddys y8 wouldnt pass ar first. all he did was seafoam in oil/gas and change plugs n fuel filter, passed. just sayin

 

Seafoam is probably the best pour in the tank injector cleaner out there. The fuel being almost empty shouldn't really make a difference, your fuel filter should get the crap out from the bottom of the tank before it gets to the injectors.

If your HC levels are only 5PPM over the limit, running a tank of premium fuel may drop the HC levels just enough to get it within limits.

 

Premium doesn't lower HC. It's harder for the engine to burn.

OP, take your car for a nice long drive down the highway (30+ minutes, preferably an hour) before bringing it to the station, and don't let it sit there. Get it hot, have it tested hot.

 

Ok. So, you guys don't think I should replace my CAT? I did drove for a long time before I went there. I got there, stopped the engine for like 5 minutes. Talked to the guy. And put it on.

I will do seafoam into gas tank tomorrow. But the guy suggested that I should replace CAT. But CAT being an expensive repair, I'm asking state for assistance. Meantime, I wanna do some stuffs that will probably let me pass without costing a lot. I still have one more chance.

 

you need to get the right ecu mapping for the motor.

 

you said you're running the stock OBD1 ECU, which could be a P28 if your car is an Si with an unchanged ECU. if so, you need to get the ECU remapped with the D16Y8 basemaps because if I recall correctly, the Y8 and Z6 are about 80% similar, but they have minor differences in their fuel and timing maps.

 

Premium can lower the HC if his car was pinging.

I would retard your timing that maximum allowed and still be able to pass smog. If it is 10 like the other mechanic said I would do that. That should take 10 to 20 minutes.

Do you want to fix the problems causing high HC or just pass and get your sticker?

 

I didn't see that you changed your dist. cap. I see rotor, though. There might be carbon buildup inside the cap weakening your spark.