1999 Tercel's emissions results

An emissions history of Tegger's Tercel back to top

Gallons are US.

		ASM2525 (25mph cruise)			Idle
Date	Item	Limit	Reading	% of limit	Limit	Reading	% of limit
Aug 2003 44,675 mi April's mpg: --- (87 octane)	HC (ppm)	76	41	53.9%	150	23	15.3%
	CO (%)	0.42	0.05	11.9%	0.70	0.02	2.9%
	NO (ppm)	580	52	9.0%	N/A	N/A	N/A
Mar 2004 48,837 mi April's mpg: 30.71 (87 octane)	HC (ppm)	76	6	7.9%	150	6	4.0%
	CO (%)	0.42	0.01	2.4%	0.70	0.00	0.0%
	NO (ppm)	580	13	2.2%	N/A	N/A	N/A
May 2006 71,956 mi April's mpg: 31.30 (91 octane)	HC (ppm)	82	19	23.2%	150	16	10.7%
	CO (%)	0.45	0.01	2.2%	0.70	0.03	4.3%
	NO (ppm)	636	543	85.4%	N/A	N/A	N/A
May 2008 99,205 mi April's mpg: 30.72 (87 octane)	HC (ppm)	82	20	24.4%	150	11	7.3%
	CO (%)	0.45	0.04	8.9%	0.70	0.02	2.9%
	NO (ppm)	636	5	0.8%	N/A	N/A	N/A

Notes:

O2 sensor is original
Catalytic converter is original.
There is no EGR system.
Oil consumption is currently about 8,000 miles per US quart
Fuel brand is unknown. 87-octane except for 2006 test, which was done on 91-octane.
Oil was changed just prior to 2004 & 2008 tests
Car was driven almost cold onto dyno for Aug 2003 test
Car was driven for one-hour highway speed immediately before 2004 and 2006 test were done.
Note the inexplicably high NO reading for 2006. I'm quite certain this was a one-time glitch that will not be repeated, much like the one I experienced in my Integra.

More history and details:

Car was purchased just before Labor Day 2003. It had to be given an emissions test before ownership could change hands, and then it had to have another one done according to my wife's birthday. Absolutely nothing except oil changes and the high-speed prep was done to the car between the first test and the second.

We have all the gas fillups going back to the purchase date, so we can determine what the exact fuel mileage was at any point.

Driving is mostly urban, with commutes to work several times a week for a half-hour. Most trips are less than a half-hour.

The car's history is mostly unknown as it was owned by Toyota Motor Credit prior to our purchase. In other words, it was an off-lease vehicle. It was the only one out of about 20 cars I looked at (over the course of a year) that had actually been maintained. The coolant and transmission fluid were clean and fresh, and the coolant was the proper Toyota red. The interior was immaculate, and from the state of the engine, I'm guessing the previous driver really did look after it.

The fuel tank is kept to as nearly full as we can all the time. Wife will take several days to run the tank down to 3/4 or 1/2, at which point she fills up. I bug her to fill up more often to minimize moisture in the tank, helping to keep water out of the fuel system. Dirt is not the enemy of your fuel system, WATER is. Water gets past fuel filters.

Spark plugs were replaced in 2006, along with air filter and plug wires.

PCV valve was changed in 2005. The original was not plugged. There is an amount of varnish visible in the oil filler cap opening, so I surmise that oil change intervals could have been a bit shorter that whatever they were. Mine took 200,000 miles to develop such varnish. Oil is now changed every 1½ months, as wife only drives about 500 miles per month.
Pictures of this engine's top end are here: http://www.tegger.com/hondafaq/misc/tercel_valves/

The car is started and allowed to sit for no more than 30 seconds before starting out, even in the worst cold weather.

The throttle body was cleaned in 2007. There was almost no carbon in it. The air filter was changed when we bought the car.

The end.