Emission

[fusion27]

Can anyone help, I got a 1989 accord that kept failing emission co at motor vehicle inspection sta., what is there to replace, as far as getting the car passes, it just had a tune-up and there is no check engine light.

Thanks
Roy

[jeffcoslacker]

Can you post the trace graph from the test? Without knowing at which points it's spiking, I can't tell you where to look.

In general, if you retard the timing slightly, and lean the mixture, it helps, but not always. Depends what the problem is.

[Igovert500]

Yeah in general that works. Another thing to try. At Pepboys they sell this stuff that gaurentees to pass emissions if you have all your stock catylitic converters functioning. I think you dump it in your gas tank. I don't really remember much about it, except that it had a red 3000gt on the can/bottle. If you ask at Pepboys though, they will know what you are talking about. I have never used the stuff, so I don't know how well it works, but that maybe a cheap way to pass.

[fusion27]

Originally Posted by jeffcoslacker

Can you post the trace graph from the test? Without knowing at which points it's spiking, I can't tell you where to look.

In general, if you retard the timing slightly, and lean the mixture, it helps, but not always. Depends what the problem is.

Thanks, I'll try that and see what happens.