Hello everyone. Hoping to get some input on this problem. I have an 83 4wd with a 22r.When I got it 2 years ago it passed smog. Don't know the numbers, but it wasn't a problem. Took it in for a smog 2 weeks ago and it failed. Prior to taking it in I did a tune up: plugs, wires, cap, air filter, rotor, and an oil change. Here are the first set of numbers: 15mph: HC- MAX-150 MEAS- 152 - FAIL CO- MAX-1.55 MEAS- .48 NO- MAX-1060 MEAS-428 25mph HC- MAX-130 MEAS-92 CO- MAX-1.36 MEAS-1.25 NO- MAX-962 MEAS-197 Stopped at a friends shop for advice and he asked about the thermostat. Suggested I replace that. Turned out it was bad, so I replaced it, and then went for a 20 min fwy drive to warm it up before the test. 2nd test results: 15mph: HC- MAX-150 MEAS- 150 CO- MAX-1.55 MEAS- .64 NO- MAX-1060 MEAS-310 25mph HC- MAX-130 MEAS-53 CO- MAX-1.36 MEAS-1.58 FAIL NO- MAX-962 MEAS-93 It had passed at 15, but now failed at 25. So back to my friends shop I go. He says to leave it there and he will take it to the shop he goes to for smog. 5 hours later, 3rd test result: 15mph: HC- MAX-150 MEAS- 150 CO- MAX-1.55 MEAS- .57 NO- MAX-1060 MEAS-480 25mph HC- MAX-130 MEAS-115 CO- MAX-1.36 MEAS-2.87 FAIL GROSS POLLUTER NO- MAX-962 MEAS-167 My friend is now telling me that he thinks it is a problem with the carb. May need to be adjusted, rebuilt, or maybe replaced. I am pretty well lost at this point. Haven't had a lot of diagnostic experience, and zero experience with carburetors. I would really appreciate any help or ideas anyone has. Thanks!
In the past, I've taken my truck into the carb specialty shop for a "pre-smog." They dial in my Weber, clean out the EGR tube and other stuff. I then I take it to the test only station. It's been a few years since I've gone this route, but it seems like you'll need to do this. Rick
Im in the middle of the same problem. All the numbers are good for me, except for the CO (in Ca., the passing # at 2500 rpm is 2.00, my 80' sr5 is blowing 4.3). Pretty frustrating, especially since a new carb is most likely in my future. The carb is stock, and if I have to replace it, I'll buy a rebuilt one. I'm going to try everything else first.
i like the idea, but if theres a problem with the way the carb is working(or any one of the 700 things it could be), I'd hate to have to keep putting band-aids on problems and just fix the issues. I'm going to replace alot of whats on the rig as it is. I just want to register and drive the damn thing.
And this is why I'm glad my truck will never have to take a smog test. In WA, cars over 30 years old they don't care how bad it is. They figure if you've kept it running for 30 years, then you know how to keep it clean.
