1988 GT 2.8L V6 with Rodney Dickman's 210F on fan switch; otherwise stock replacement repairs; 174000 miles. The Cataclysmic Perverter is not the original, but I don't know when it was replaced. Before any testing I replaced the O2 sensor, EGR valve and solenoid due to code 32; it idles between 900-1000 (typical wandering) when warm so I assumed the EGR tube was okay.

1st test passed all but NOx
Test: reading - limit - result
HC: 99.2 - 168 - Pass
CO: 0.69 - 1.08 - Pass
NO: 1986.6 - 1208 - FAIL
CO2: 14.03 - N/A - N/A

I read about using ethanol (denatured alcohol) or methanol online; so I thought I'd try it. I mixed about 0.75 gallons of E85 (85% corn ethanol) with 1.75 premium unleaded and added to my tank when low (not exactly sure how low, the gas guage is off a bit). I estimate that I had another gallon or two maybe more in the tank resulting in somewhere less than 15% ethanol for the second test. I also removed the rodney dickman fan switch and replaced with original.

2nd test passed all but NOx
Test: reading - limit - result
HC: 78.5 - 168 - Pass
CO: 0.70 - 1.08 - Pass
NO: 1556.1 - 1208 - FAIL
CO2: 13.05 - N/A - N/A

Since it got me half way there, if I double my ethanol mix, should I pass? My next guess is to replace the cataclysmic perverter? Can I just pick one up that will fit, or do I need to special order? Any other tricks, tips, thoughts, etc. all appreciated.

Thanks

Running methanol through a Fiero's engine isnt a very good idea. For one, it has a tendancy to make rubber gaskets disappear. And there's a rubber hose in the fuel tank that's already old enough to fail. Fair bit of work to change it.

Anyway, did you get tested right after a long drive to get well up into temps, or after sitting around for a half hour, letting the engine cool down? Makes a big difference.
A bad cat will bring up NOx readings, but there are people here without cats who still manage to pass. So something else is probably not quite right. I don't know the V6 well enough to say what though.

Yes, I took it for a good long hard drive at high RPMs. Got it all warmed up at high speed, then let it idle while in line for a while, kept it up to temp and never shut it off before the testing. Still no dice. Any body else.

I know that methanol / ethanol and rubber don't mix, but I really need to pass Echeck before I tear into the front end, so I gave it a shot. I am not going to run it long term.

Retard your timing.
Move the ignition timing down about 2* (if 12* set it for 10*, If 10* set it for 8*)
Spray throttle body cleaner spray down the throttle body and plenum.
Verify the EGR tube is not cracked.
Install a cooler thermostat like 165* or 175* (Or just remove the thermostat for the Echeck.)
fill gas tank with premium gas.


NOx is caused by high head temps. You are probably running a little lean and the EGR can't compensate.
Retarding the timing and cleaning out the intake should help alot.
The catalytic really doesn't do much for NOx so I doubt yours is bad.

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http://www.ohioecheck.org/
When a vehicle has failed at least one emissions test and the owner has made efforts to have that vehicle repaired, a waiver may be issued at an E-Check test facility. The motorist must bring all original emissions-related repair receipts, as well as the vehicle, to the station in order for a waiver to be issued. Repairs may be performed at any repair facility or by the vehicle owner. In the case of self-repairs, only receipts for parts will count toward a waiver. An owner may not submit receipts for her/his own labor. Tampering-related repairs do not count towards either waiver option. Note: waivers are not transferable to the new owner if the vehicle is sold. Warranty repairs do not apply to the waiver limit requirements.

Option 1 - Applies to the Tailpipe Test Only:

CONDITIONAL PASS WAIVERS are issued after the initial tailpipe test. To qualify for this waiver, the vehicle must be a 1995 or older model year and must show:

a) at least a 30 percent improvement from the initial emissions readings for which the vehicle failed without causing initially passed readings to exceed state standards; AND
b) eligible receipts for emissions-related repairs totaling at least $200. Tampering-related repairs do not count towards this option. Receipts will only be accepted for repairs performed within sixty days of the initial inspection.
The above type of waiver applies only to vehicles tested via the tailpipe test.

Option 2 - Applies to Both OBD II and Tailpipe Tests:

REPAIR CAP WAIVERS are issued to motorists when they have spent $300 or more towards emissions-related repairs on a vehicle and still do not pass. In the case of the tailpipe test, this waiver does not require any improvements in the pollutant(s) for which the vehicle failed. As with the base waiver (conditional pass), tampering-related repairs do not count towards this option. Receipts will only be accepted for repairs performed within sixty days of the initial inspection.

Waivers are issued at the E-Check test facilities. For the E-Check test facility nearest you, contact 1-800-CAR-TEST.

Oreif has it correct. nox is high head temps. you may want to verify that the egr passages are not clogged solid with carbon, a very common problem. aftermarket egr valves sometimes use a restrictor gasket for differrent cars, these clog easily.
retarding the timing a few degrees will also help lower the temps.
if all else fails, forget the methanol, get a bottle of octane 104 emmisions cleaner, in the green bottle. that should do the trick.

Thanks for the input everyone, I'm trying again tomorrow morning, keep your fingers crossed for me.

Gokart, I have read that many times in the last two weeks. Unfortunately, even though I installed my new EGR components within 60 days, I purchased them nearly two years ago. That's almost $200 that doesn't count.

Oreif, I don't know how to set timing. Is there a thread that can explain it well enough for me? Before any testing I replaced cap, rotor, wires, plugs, rodney's SS vacuum lines, the EGR valve and solenoid. How do I verify no leaks in the tube? The idle is normal (900-1000) and it has the sheilding intact. I held a hose to my ear and tried to listen for leaks, but I didn't notice anything (very untrained ear). My cooling system is working well. Do coolant temperatures really affect combustion temperatures enough to make NOx a problem?

I had the intake out to put on the vacuum lines, and although I didn't clean it fully as I should have, I made sure the EGR passage wasn't bloked shut. If its not the catalytic converter, what's wrong with my car? I don't want it to run lean and blow up.

tjm4fun, I removed a restrictor gasket from the EGR system when I replaced it and I made sure the passages weren't plugged completely. Where can I get this, "octane 104 emmisions cleaner"?

lost all the goodies inside my 2 year old napa cat, caused it to fail just like that.

goodluck

I thought using premium fuel in the Fiero hurt your chances of passing especially in a high mileage engine since it doesn't have the compression necessary to burn it efficiently. I recall my first experience with 93 octane in a 2.8L; immediately higher operating temperature and noticeable loss of power on acceleration.

Ha HA! I passed, thanks to ethanol...now I just have to get that crap out of my car and change the fuel filter, etc. I still would like to know why my car is running lean, and how to fix it? Should I try another new O2 sensor?

3rd test passed all including NOx
Test: reading - limit - result
HC: 39.1 - 168 - Pass
CO: 0.55 - 1.08 - Pass
NO: 1050.9 - 1208 - Pass
CO2: 14.29 - N/A - N/A

Thanks to all who gave advice - ethanol or alcohol really works.

quote Originally posted by TG oreiF 8891: Ha HA! I passed, thanks to ethanol...now I just have to get that crap out of my car and change the fuel filter, etc. I still would like to know why my car is running lean, and how to fix it? Should I try another new O2 sensor? 3rd test passed all including NOx Test: reading - limit - result HC: 39.1 - 168 - Pass CO: 0.55 - 1.08 - Pass NO: 1050.9 - 1208 - Pass CO2: 14.29 - N/A - N/A Thanks to all who gave advice - ethanol or alcohol really works.

Congrats on the pass. Now to fix the lean issue, I would check the fuel pressure regulator, fuel filter, and the fuel pump for proper pressures.
You could also pull the injectors and have them cleaned and balanced. (They clean them out and adjust the fuel spray so each injector sprays the same.) I would look at fuel delivery before swapping more sensors.

Thanks Oreif, what pressure am I looking for? I know the fuel filter is old, and now that I've run ethanol its probably quite plugged. I already have a new one and I will replace it. While I am in there I would like to check the fuel pressure. Where can I get a guage that will screw on where the filter goes and about what pressure am I looking to get?

Where are you from in Cleveland... I live in Parma by Pearl and Brookpark. I have a few sets of pressure gauges and an extra Fiero repiar book to lend out.