Hello,
I recently got an 81 2wd Toyota truck that is in decent shape. I live in California and need to get it smogged. I took the truck to a repair shop expecting it to fail the smog test based on what the previous owner told me. The repair shop tested it and it passes on their machine, but based on goofy CAlifornia smog regulations I need to smog it at a different shop to be legal. I drove down the street about 80 yards from the first shop to a second smog shop where it failed the test. Nothing changed from one the first shop to the second except for that the dynamometer at the first shop is raised out of the ground and the vehicle is tested with the back end raised in the air a couple of feet, and the second shop the vehicle is tested flat.

the test numbers were as follows

________Shop 1___shop 2
co2_____13.21____12.2
o2______2.02_____2.4
HC______54______128
CO_____.35______1.55
NO______51______77

The truck only failed the smog test under carbon monoxide, and it only just failed. The high CO reading means a rich mixture. Could having the back end of the truck up in the air for the first test, when it passed, have done something weird with the floats in the carb and caused it to lean out a little bit?

If anyone has any ideas or things that I could check that would be a big help.

-David

 

do a tune up on it, play with the settings on the carburator. my old 66 chevy would pass smog in cali(wanted it to be clean, so made sure it would, wasnt necessary though, pre1975) with a simple carburator adjustment. i would tell ya how to adjust the carburator, but i have no idea on those carburators, only carburator i know how to adjust are the old 350 engines and up. for the record, my carburator was a holley 850 racing carb, and it passed smog. if that can pass smog, there is NO reason why a yota cant. you get me? best thing to do is lower the performance of the carburator, get it to pass, then re-adjust. here is a site that may help you out, i just hope you have the 22R, not the 20R, since the page is for the 22R.
http://www.bluebassdesign.com/boonin/carb_faq/
good luck
BTW, a lot of people here have carbs in their truck, and could help you much more than i could. welcome.

 

Thanks for the link, I think that might be a little helpful.

I don't really have any idea how to adjust the carb either, which is why I was asking here. I figured that someone might have an idea.

How does the fuel level in the float bowl affect mixture? When the truck is flat and running the fuel is right at the bottom of the sight glass, when I have it in my driveway with the back end up then the fuel level is about halfway up the sight glass. The angle of the truck was the only difference between the two smog stations. Does this make any sense at all?

-David