Hello hT! I've been having a problem trying to get my accord to pass smog. It fails the 25mph idle test on CO% with a 0.99 (max is .49) everything passed with flying colors. The smog dude says I need to replace my cat but it's only 3 and a half yrs old, also replaced 02 with an oem one 2 yrs ago last smog. The car runs pretty rich,I estimate 18-22 mpg and it hiccups slightly during idle. And also the tires were super low on air pressure.
Stuff I replaced:
-new distributor with cap/rotor
I am going to change the oil and filter as well as the plugs tomorrow. I will clean my 02 sensor with lemon juice (it works perfect on 200k mile junkyard bosch lsu sensors for my wideband)
Also thinking it might be my ect because one of my radiator fans wont kick on.....not sure.
Car is a 1993 accord lx with 160k
thanks again any help is greatly appreciated!

 

Post your complete readout.
If you are in Calif, post your 5 gas readout.
Just because the other gas readings 'pass' doesn't mean they are correct for your application.

 

 

I completely missed that I also failed HC too

 

Yup.

Verify that your exhaust manifold and exhaust is not cracked or leaking allowing false air getting to the O2 sensor, this would cause a false 'lean' condition and the ECU will dump fuel calculating that the engine needs more fuel when it doesn't.
Even though it is running rich your NOx is high at 25MPH.
With 160K miles your EGR ports are most likely clogged. You will need to remove the plugs in each individual runner and clean them of carbon. Usually the EGR main feed does not get clogged, its just at the runners.
https://www.hondaaccordforum.com/for...ned-t2t013.pdf
Replacement EGR runner port plugs are P/N 17199-PT3-AHM
Or located similar sized 'freeze' plugs from your local auto parts store.

 

Today I got to work on the car and inspected for cracks on the manifold and found none.I also inspected the filter and it was filthy, it had sticks and bird feathers in it.
I also got a pic of the o2 sensor, it seems to look okay. Also pulled on the egr valve to see if it stalls (apparently that shows that it works) it only hesistated slightly but no where near a stall. Im gonna start to drill out the egr plugs tomorrow.....I got it started today, but i ran out of sunlight and could not get a screw tapped through. One last thing I noted is that the car is starting to run rougher and rougher ,it wants to stall as soon I throw it in reverse or drive, but it seems to run better when I pull a vacuum line off.

 

just got the plugs cleaned out and 2/6 were pretty clogged. car drives really good now, I also adjusted the idle via throtle body cable and it feels steady but still has a rough idle at 8-1000k rpms.......maybe sparkplugs?

 

Idle is not adjusted at the TB cable.
Back that off. Do not touch the ilde stop screw either, that is set at the factory.
Idle(when hot) is 700rpm ±50rpm. (650-750rpm)
If the idle is low the TB may be coked up and need some simple cleaning, use a clean rag soaked with TB cleaner and wipe the ID of the TB and the edges of the TB butterfly.
Remove the IACV and inspect that the filter screen is not clogged with carbon and soot.
DO NOT SPRAY CLEANER INSIDE THE IACV. This will get past the seal and strip the coil of insulation killing the IACV. Same with the engine off, don't spray anything in the IACV port, only down the TB throat to clean out any gunk.
If the idle bounces around, you may want to look at the FITV, FAQ at the top of the page has a How-To.

 

Ok finished cleaning and backed of the throttle cable bolts, the idle stays at 700 rpm but its rough, I'm tthinking because the plugs are fouled that it wont burn the fuel completly. I'm going to change them real quick and see if it helps.

 

I just changed the plugs and now it feels like a completly different car. The idle is much smoother and the transmission engages better. My guess is that it is running rich due to a weak spark.