90 civic high hydrocarbons

[james kremer]

I just put my car through Aircare(emissions testing) and it passed everything exept for reading high on hydrocarbons on the idle test. Does anyone know how to bring these numbers down. It's a 1990 civic with the 1.5 litre, 245,000 kms. New sp-plugs,fresh filters(air-oil),new muffler and new oil.

[Smoghog]

Originally Posted by james kremer

I just put my car through Aircare(emissions testing) and it passed everything exept for reading high on hydrocarbons on the idle test. Does anyone know how to bring these numbers down. It's a 1990 civic with the 1.5 litre, 245,000 kms. New sp-plugs,fresh filters(air-oil),new muffler and new oil.

Wow 245k Hc's are raw fuel, so it could be...

Purge canister full
leaky inj
Fuel pressure reg

O2. See if it is baised lean
I think 90's have map sensor, check all vacuum lines. Yes, some can cause rich cond
Coolant temp sensor
octane in fuel, for emissions run low grade (unless specified) 87 burns easier that 92.

How bad is it? are you way over the limit or close?

SH

[arodg25]

i had the exact same problem. i adjusted the valves and fuel filter and then passed with flying colors. also go to the coquitlam aircare on united blvd. I never fail there. also change your oil. it never hurts.

[james kremer]

Max allowable HC's are 116 ppm. My car read 157 ppm. It's not extreme, but it's enough. Thought maybe the o2 sensor! Don't have alot of money to spend on it,or time, so any easy fix's! also has new fuel filter

[arodg25]

my car read around 260's when i failed. and went down to 30 when i passed. adjust your valves. its easy, free and only takes about 20-30 min

[arodg25]

also you could put a 1L bottle of methal hydrate into a half tank of gas. thats an old trick.

[james kremer]

I've never adjusted valvles before.Are there any quick tips. btw, thanks for the reply.

[arodg25]

if you've never done it before, just get a manual. all you need is a 10mm wrench, a flathead screwdriver and some depth guages. i cant think of any tips its pretty much how the manual with describe it. good luck.

[livinincalifornia]

adjusting valves...I wouldn't think that would make that much of a difference as far as HC goes. I would work more on the fuel managment system, go with the O2 sensor and work your way up from there. Also since it's at idle you might want to clean out your idle air control valve, if it doesn't help it's good maintaince anyhow. Also see if you're throwing any codes from the ECU..I was able to pass california emissions with an error code but it was way close, if you're throwing codes you'll burn rich.

[arodg25]

if your exhaust valves arent to spec then they could be letting unburnt gas into the exhaust giving you a high HC reading.

[james kremer]

How do i retreave the codes!

[livinincalifornia]

it's under the carpet in the passenger foot well...unscrewed the huge plastic screw things in the carpet, pull it back and there the ECU is...there's an LED in the middle of it, turn the car in the ON position and it should blink once to show it's working, if you see it keep blinking then count how many times it blinks and tell us.

[james kremer]

I did what you said and it only blinked once when i first turned the ignition on.It's not giving me anything else,which i hope is a good thing. I never knew it existed. I'll try replacing the 02 sensor and go from there. I just don't want to keep running back and forth to aircare at 23 bucks a pop! Btw where is the idle air control valve?,and thanks for the help so far.

[91CRXTC]

the iacv is on the back of the mannifold to the right of the throttle body. its got 2 hoses connected to the underside and is held on with 2 12mm scews. I was told to spray this unit with brake cleaner or degreaser, i guess u just have to watchout for the wire connector on the side. Ah shit if its a dpfi manny then i am probably wrong about its location, and hopefully someone here will let you know(sorry). G/L

[dfarres]

Buy a little red bottle of RxP.... i did a tune up and added a bottle, ran it for about 60miles and my numbers were cut in half.