California Testing: I'll have to check, but apparently the emission standards categories (ESC) are different for the 1985 and the 1989. You're right about AVE being the average emissions for passing cars, but only for those in that same ESC. The purpose for AVE is to emphasize how failing by "only a little bit" is really pretty dirty compared with a good running car in that same emission control technology class. As far as model year vs technology, the XR4ti EEC-IV was exceptional in 1985, but not in 1989. Feedback carbs were normal equipment for most of the new car population in 1985.

The ESC tables are published on the California Smog Check web pages at <www.smogcheck.ca.gov>. Look in the information for technicians.

There can be variability in the way the test is performed, although there are many algorithms in the software to keep the tests consistent. Control of "acceleration excursions" was originally tighter, but technicians new to the BAR97 dynamometer systems were unable to perform the drive trace without making errors which caused the test to abort. Therefore, some test even on the same vehicle will have higher emissions, but usually still well within the emission standards.

Fixes

For those of you who have failed a smog test b/c of too high of a NoX reading. I had a full tune up and every thing was balls on but I failed with too high NoX by over 1000ppm. I rechecked every thing and I found nothing wrong. Then I remembered reading that Methanol had really low NoX levels. And from another article that Methanol could be added to your car without any ill effects by up to 3%. So I added Trick racing methanol to a full tank of premium unleaded for a 3% mixture. I tested again and passed. HC and NO levels came up slightly but my NoX levels droped by over 1000ppm and I PASSED! :)

Results

	RPM	%CO2	%O2	HC(ppm)			CO%			NOx(ppm)			Result
				MAX	AVE	MEAS	MAX	AVE	MEAS	MAX	AVE	MEAS
1985MerkurXR4Ti,5sp,stock no mods,168000mi
15 mph	2887	14.9	0.3	163	43	30	0.85	0.18	0.05	2170	394	702	Pass
25 mph	2517	15	0.1	113	24	28	0.65	0.13	0.19	1970	397	297	Pass
1989MerkurXR4Ti,5sp,stock no mods,120000mi
15 mph	2678	13.9	0.5	141	30	68	0.74	0.14	0.6	9999	206	504	Pass
25 mph	2463	14.5	0.1	91	12	41	0.62	0.07	0.12	9999	194	159	Pass
1989MerkurXR4Ti,5sp,stock,no mods,96000mi
15 mph	1455	8.2	9.4	141	30	108	0.74	0.14	0.18	1992	209	238	pass
25 mph	1679	7.8	9.8	91	12	80	0.62	0.07	0.21	1792	194	293	pass
1985MerkurXR4Ti,5sp,stock no mods,168000mi
15 mph	2887	14.9	0.3	163	43	30	0.85	0.18	0.05	2170	394	702	Pass
25 mph	2517	15	0.1	113	24	28	0.65	0.13	0.19	1970	397	297	Pass
1985 Merkur XR4Ti, 5sp, big valve NA head, 8.5:1 compression, SVO EEC & VAF, IC, 96,000mi, 12° advance, ported everything
15 mph	2817	14.9	0.1	163	43	1	0.85	0.18	0.20	1670	394	208	Pass
25 mph	2508	14.9	0.1	113	24	2	0.65	0.13	0.17	1470	397	251	Pass

BTW, the Smog Check Inspection Manual has an appendix (K?) that says that intercooler retrofits are permissible without an ARB E.O. if installed on an engine with OEM turbo. Count me in!