Hello,
I've been trying to pass emissions here in Arizona. I'll list the parts I've fixed so far. O2 sensor, catalytic converter, spark plugs, vacuum leak in intake tube and purge tank and oil changed as well. Now I've failed with high emissions every time. I've checked my plugs today and they're black, covered in carbon build up. I don't think it's a lack of spark but not sure. Next on my list of repairs are, new plugs, new plug wires and a new distributor. Is there anything else I could be overlooking? I've heard my ignition timing could be off. But if anyone has had this problem before and found out what it was let me know. Any advice or questions welcomed. I've only had the car since July and the owner before me used the one time waiver and all the 3 day tags, soy car is parked until I pass emissions.

Thank you,
SLOWEF1990

 

I would do the wires and plugs before the dizzy. Are they telling you the exact failing reason? You said you did a cat but are you hearing any noises that might indicate that the " hive" inside is loose? Also, what is the law for classic car's in AZ and how old does your car have to be? Do they let you bypass it if you register it for a classic?

 

Spark plugs and wires are ordered in route now. And I did have a shop look over my car and they found that my old cat rattled really bad. I took it off and it sounded like a maraca lol. It had pieces falling out black burnt just horrible shape, so I assumed it was that. I replaced it and took it off recently to get to my O2 sensor (took off the cat and some of the other exhaust parts for easier access) the cat was in good shape still no rattling. But after I changed my O2 sensor and bolted everything back on, went to do emissions and it failed more than the first time. I do also have a hole on my exhaust right before the rear driver side wheel idk if that would effect performance at all but going to order a new exhaust pipe anyway. Here are my HC and CO test results. Loaded reading: HC:327/ standard is 220. Loaded reading : CO:4.66/ standard is 1.20 failed both. Idle reading: HC:770/ standard is 220. Idle reading: CO: 7.62/ standard is 1.20. So its it's pretty bad. As far as registering as a classic car I'd still have to do emissions I'd just get the historic plate, which isn't worth it lol. I don't want to register it out of town, doing that means no emissions but I don't like to cut corners.

 

those are some high numbers. Check your EGR valve as well. May not be doing its job properly and causing the unrecirculated gases to go out the exhaust and give those high-*** readings

 

What are the local emissions laws like in Arizona? I'm in Texas and any car over 25 years isn't required to pass an emissions test, just a safety inspection (lights, seat belt, etc.).

 

If your plugs are black, you have poor fuel control and not necessarily bad spark. First thing to do is set ignition timing dead on (red mark on crank). If you are advanced timing, you will fail emissions (ask me how I know). Second, set idle speed. Third, I would recommend E3 spark plugs as they tend to have a good burn characteristic. Make sure to reset your ECU after doing these changes. I would also check your idle vacuum. You should be close to 20-22in/Hg. If you have a vacuum leak it will show here. I would not change your plug wires unless they are very old or you have a misfire issue as well. Does your motor have aftermarket add ons? If so, what?

Also, make sure your O2 sensor is fully tight.

 

Update: I took my car to an emissions specific shop and had them run diagnostics on my EF. Turns out my verdict was my ECU is bad. I was told my sensors were not reading properly. I'm going to order a refurbished ECU from rockauto I guess that explains why I change something it makes it worse. I'm not too sure if they're correct but I'll change it anyway, new plugs, plug wires, fuel injectors are here waiting on my ECU. Is there a break-in or relearn process after installing a new ECU? No simple explanation online for my D15B2. Any advice is always appreciated. Also, my car passed emissions after running it really lean so that problem is solved for now.

 

There is a relearn but it is the same as if you reset your current ECU. Nothing unique. I hope they are right. I am assuming they checked your timing, etc? Did you have any check engine lights during these issues?

 

No check engine lights during the time I've owned it. They said my timing was good and everything looked good but I'm thinking about getting a second opinion before I spend $200 on a new ECU.

 

I would like to know how they came to the conclusion the ECU was the issue. I would get a 2nd opinion as well. You need a good quality shop - maybe one that specializes in imports.

 

The specialty shop in my area is booked for awhile. So I'm just replacing things I know need changed. I did clean off my air intake temperature sensor I believe it's called, and I noticed my car had slightly better acceleration. One bit of info I did forget to share was when I try to accelerate hard my car does seem to rev high and not engage as if my car was in neutral, I assume that's probably my trans slipping since it has over 238,000 miles on it, but if all these problems are related to my ECU could my transmission be affected by my ECU as well? Like I've stated in the past, new to the car game.