Well i failed both parts of my emissions testing...ugh. I failed both the hydrocarbon test and the carbon monoxide. Wondering if this could be the result of a bad o2 sensor. Also, i was told my catalytic converter was new just before i bought it this past summer. Now, it also passed emissions in california, which i hear is pretty strict compared to other states. My head was just machined, because of a headgasket install. They must of had it apart because of the new valve stem seals that they installed. I don't get any smoke out my exhaust either when i step on it. Any help would be much appreciated.
failed emissions
- Thread starter huntin5L
- Start date
did they give you any more information? what state are you in?
do you have any fuel mods? what are your other mods?
do you have any fuel mods? what are your other mods?
hmm, well if your exhaust has a hole in it, that might be the problem... 
seriously though... are you throwing any codes? a bad o2 sensor also, could be causing you to run very rich.
seriously though... are you throwing any codes? a bad o2 sensor also, could be causing you to run very rich.found it. Getting code 11. Momentary interruption in power supply to ecu, which was probably caused when he disconnected the battery when it was getting worked on. Also, it costs 147 dollars for an 02 for the car, wondering if i should try going with the cheaper bosche one that they make. Also, it does seem like im getting pretty bad gas mileage, i wonder if this is all from my o2 sensor.
02 has ALOT to do with fuel mixture. You can put a new one in yourself for about $40-65. If the leak in the exhaust was serious, you would have come up with lean readings, and not rich ones.
Those #s sound backwards. CO% would be something like 0.80, and HCs like 105.
Calif Max HCs for my '89 N/A is 106ppm @ 15mph, & 81ppm @ 25mph.
CO% max 0.70 & 0.57....NOx max 762ppm & 701ppm
Those #s sound backwards. CO% would be something like 0.80, and HCs like 105.
Calif Max HCs for my '89 N/A is 106ppm @ 15mph, & 81ppm @ 25mph.
CO% max 0.70 & 0.57....NOx max 762ppm & 701ppm
check out the Group Buy section, there's a great deal on O2 sensors from MDCMotorsports right now... like 38 plus shipping or something like that. Then all you need is solder, a soldering iron, shrink wrap and a hair dryer/heat gun, and you've got yourself a new o2 sensor. The toyota one is more $$ because it has a plug that comes with it so it just snaps on... but what's 10 minutes of soldering to save 100.00? I would bet that's your problem.
I would bet that's your problem.i dont think the egr valve would be causing numbers that off.... are you getting bad gas mileage too? that's a sure indicator of a bad o2 sensor.
yeah, i think my gas mileage is pretty bad. I assumed that was normal, but now i wonder. Let me ask you this, if i hit fuel cut and don't clear the code do you think that might make me run lean. Better put does, the a/f get altered when you hit fuel cut?
huntin5L said:
EGR (working properly) won't effect fuel mixture. If its inop, it won't either. 02 will effect mixture. Fuel cut should not cause your mixture to change and stay lean or rich when back to normal rpms.
Your 02 can be bad, or starting to fail, and not set a code. My car ran much better with new 02. Bosch w/plug on wire. I passed smog test fine with old 02.
A good running engine should get at least 15mpg city.
huntin5L said:
If you back the timing to about 3-5* before the test, it lowers the NOx.:biglaugh: