Need '88 CRX-si Emissions Help

Failed emissions testing on CO only. I haven't looked at the car since the test, but am wondering if there is one common reason for this. Thanks for any help. Jim

The one thing I can think of you might try is cleaning the throttle body. I don't remember why, but when they get cruded up on certain vintage of "d" series engines, it causes emissions issues.

Unmodified Hondas usually pass with no problem. My dad's 85 CRX gets driven daily and passes with flying colors. Maybe run some fuel system cleaner through it and try again, make sure the cat is nice and hot. If it fails again check to see if the cat is lighting off or not. How does it run / drive? And what kind of mpg does it get?

easiest fix ? move to NC ... the only vehicles that have to pass are '96 and newer

wbjones wrote: easiest fix ? move to NC ... the only vehicles that have to pass are '96 and newer

Thanks. That was useful.

When my mercedes is tuned they use a CO meter to tune the mixture. I'm pretty sure the deal is Rich mixture = high CO, lean mixture = high NOx. Don't know if it will help you any, good luck.

I got to fight smog for 2 years and every month or two I had to get a temporary registration. By the time my car did smog I had almost every temp sticker you could ever want.

Yeah, high CO means rich mixture. I can smell in out the exhaust pipe. I checked out all the tune-up parts and everything is good. But I swapped them out for a known good set anyway - no change. Fuel pressure is correct. Air filter is clean. No trouble codes. I think tonight I'm going to clean the throttle body as was suggested, run Seafoam through it and get it re-tested tomorrow. I would appreciate any other tips/ideas any of you guys might have.

If it's borderline, fill it with 1 gallon of high-octane gasoline and 1 gallon of wood alcohol (A.K.A. Methanol). It will burn leaner due to the alcohol content, and generally cleaner as well. I did this with my girlfriends 88 civic wagon that wasn't passing due to NOx. It lowered the NOx due to the cooler burn of the methanol, but I noticed that it dropped the CO emissions a bit as well. YMMV.

Don't forget to drive it hard on the way to the testing station to get the catalytic converter nice and hot!

The one thing I can think of you might try is cleaning the throttle body.

Can't hurt. My buddy spent hundreds of dollars and hours upon hours trying to get his 1st gen. to pass. Finally cleaned the dog-snot out of the TB and it passed with flying colors!

Something came up and I couldn't work on it last night, but am wondering why would cleaning the throttle body make such a difference? BTW, my CO was 2111 on a 1512 limit. Everything else was way under the limit.