High Hydrocarbons / deq and idle issues!!

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duster97
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My tercel:: 1985 tercel 2wd

High Hydrocarbons / deq and idle issues!!

Post by duster97 »

Hello. My name is dustin, I live in Oregon and I am having some issues with a 1985 toyota 2wd that i purchased. hydrocarbons at deq is my main issue, but let me explain the process I have gone through so far..

I bought the car about two weeks ago. I had to wait for my license to get reinstated in alaska as it was suspended, so I did a little work on the car while I waited for that to go through. There was a tiny little valve knock when i purchased it, so i got rid of that noise by adjusting the rocker arms a little bit and sealed the valve cover back up with a new gasket and some rvt. replaced plugs, air filter, fuel filter, changed oil and filter. I noticed that my mechanical fuel pump was leaking - the gaskets are a little ripped. I couldn't find replacement gaskets in town so I ordered a new fuel pump and gaskets online, should be here tomorrow. Before I did this tune up the distributor was set all the way forward (towards the grill of the car). I noticed that after I did this tune up it was gutless under a load and wouldn't idle correctly until I advanced the dist. all the way back(towards the firewall) now I am hearing a clicking at a low to mid rev, goes away at a high rev. A misfire perhaps because of the dist? I tested all the wires and plugs. The plug on my first and third cylinders are coming out black and carboned up. Also the plug out of the first cylinder was a little wet with gas even. At the deq station I am getting huge amounts of HC at the deq station. like 847 at idle and 1400 at a higher rev. Co2 emission is within standards, but my HC is pretty High. Also now the fuel has started leaking even worse, so now Im not doing a whole lot till i get that pump and gaskets tomorrow. Would the fuel pump gaskets leaking affect the performance of the car?? Also alot of the emissions stuff has been taken out of the car. hoses are plugged, etc. But i have passed deq before with a car that had missing and plugged hoses/ emission parts. I have pictures but says the file is too large to bring into the thread

So i guess what I need help with mainly is getting my HC down to an acceptable level. Im almost certain I have a misfire going on and thats why my #1 spark plug is coming out like that. The thing idles rough as well. I am hoping that once I get the fuel pump and gaskets and seal up the valves covers, adjust the dist. and fuel to air mixture that I will pass the deq. Any insight on this would be greatly appreciated it
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dlb
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Re: High Hydrocarbons / deq and idle issues!!

Post by dlb »

if your first cylinder spark plug is wet with gas, the AAP diaphragm on the carb is probably ruptured. it is normally activated by manifold vacuum when the engine is cold so if the diaphragm is broken, the manifold vacuum just sucks the gas into the first cylinder runner on the intake. plug the AAP port and hose that goes to it until you can replace the diaphragm. this can be done without removing the carb but the only place to get the new diaphragm is in a carb rebuild kit, which is about $40. the AAP is located at the front right corner of the carb.

i'm not sure about the other stuff but there are actually several really good threads here on passing emissions requirements. other members in similar situations have posted their emissions #s and worked through it so use the search to look those threads up.
duster97
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Re: High Hydrocarbons / deq and idle issues!!

Post by duster97 »

Ok I plugged off the aap and my 1 st cylinder isn't getting excessive gas anymore. Plug coming out looks fine now. Still waiting on my fuel pump and gaskets in the mail. I suspect that it's still running a little rough because of that seal being compromised. Will report back once I get that in order and run through deq again
duster97
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Re: High Hydrocarbons / deq and idle issues!!

Post by duster97 »

Well I fixed my misfire I had going on, which was a bad spark plug. Ran through deq again and I'm just barley not passing. My hc is down from 1400 to like 296. I need to get it down to 200. You think just driving it around a few days will burn some of the residual unburnt gas I had in my cylinder that was misfiring and bring my levels down enough to pass?
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Re: High Hydrocarbons / deq and idle issues!!

Post by irowiki »

Are you getting the car up to full temp before doing the emissions test? 30-45 minutes of highway driving, get it hot!
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duster97
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Re: High Hydrocarbons / deq and idle issues!!

Post by duster97 »

I drove it for like 20 to 25 mins before the test, before I go next time I'll drive it for like an hour just to be safe. The first time I went my hc was over 2000. I fixed a bad spark plug which was giving me a misfire and adjusted the distributor and it running great again, but just need to shed like 100 more hc

These are my reading

Co std. Co+co2. Hc. Co. Co2

1st idle. 1. 6. 363. .0194. 7.9
2nd idle. 1. 6. 291. .0000. 7.9
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Petros
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Re: High Hydrocarbons / deq and idle issues!!

Post by Petros »

look for a gasket or vacuum leak, running too rich or too lean can result in too high h/c readings. you also might give it a seafoam and gum out treatment to clean out the combustion chamber of carbon build up. There should not be excess fuel lingering in the engine, the sourse of excess h/c is from some thing else.

Good luck.
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duster97
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Re: High Hydrocarbons / deq and idle issues!!

Post by duster97 »

Some time has passed since my last post. I've still been having some issues with hydro carbons. Since my last post I also installed a new weber carb and she seems to be running great, but still can't get it to pass deq. When my dist. Is turned all the way clockwise it seems to run smooth, but hc levels are thru the roof. When I turn it all the way counter clockwise it runs gutless under a load, but my hc levels drop significantly damn near passed. I believe I have some sort of misfire going on still. When I unplug the wire from the 4th cylinder there's really no noticeable difference in the running of the engine though. Ive checked the cap, rotor, and plugs. I know that the plug is good though because I've switched it around with other plugs in the motor. I've tinkered around with the dist a whole lot and my roomate who is also an avid toyota mechanic suggests that I re time to stock and maybe do a compression test as well I still haven't tried the sea foam suggestion, but I think my issue is timing or perhaps a weak spark or something. What do you guys think? Also I'm running no vacuum lines whatsoever, everything is plugged up. I got the weber because when I bought the tercel it had no tvsv and no spider lines. Almost all the lines were plugged already anyway
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dlb
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Re: High Hydrocarbons / deq and idle issues!!

Post by dlb »

do a compression test. no point throwing more parts at it if the cylinder has no compression. if that appears fine, try switching the wires around to see if the 4th cylinder wire is to blame.

turning the dizzy clockwise advances the timing, counter clockwise retards it. retarded timing decreases HC levels, advancing it increases them.

have you checked for vacuum leaks?
duster97
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Re: High Hydrocarbons / deq and idle issues!!

Post by duster97 »

I have my vacuum lines all plugged off currently, but I'll do a double check in the morning. Does the brake booster run off vacuum? I'm asking this cause my e brake light is always on. I currently have no vacuums going to my carb. Everything is plugged off
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dlb
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Re: High Hydrocarbons / deq and idle issues!!

Post by dlb »

oh you have a weber. well, check #14 in the faq:

viewtopic.php?f=2&t=7442

and yes, the brake booster runs off of vacuum. a big hose goes right from the intake manifold to the brake booster. that wouldn't cause your brake light to be on though. check that out asap. make sure your brake fluid level is within spec, and if it isn't, find that leak and fix it.
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Petros
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Re: High Hydrocarbons / deq and idle issues!!

Post by Petros »

check your brake fluid level, if it is low, that is usually the reason the brake light stays on. The brake booster draws vacuum for the #4 cyl. intake runner, if the line or the booster leaks it will make the #4 too lean to run and may be the reason for the high HC (too lean or too rich causes high HC). It would not be good to drive withut the brake booster because the brakes are barely adequate as it is, but to just pass emissions it may be what you have to do.

You should always run the spark timing as far advanced as you can make get without pinging or detonation. but it will not pass emissions with it advanced, the thing to do is find out and fix why you have no power in one cylinders, corrected it and than pass emissions with the timing retarded. After that reset the timing to 10 or 12 deg. or as much advance as you can get without pinging. You get better fuel economy and power with more spark advance as long as you are not getting pinging. Retarding the timing should reduce NOx emissions, perhaps the others as well. It is bad for the engine to run for very long with the factory spec retarded spark timing, it will cause the valves to over heat and break off, trashing the engine.

You also might get a set of weber jets (they do not cost much) and swap them around to lean the mixture a bit and see if that brings the HC down, there is a weber thread where people share what jet and air bleeds they are using. Webers are never jetted perfectly for the car they are sold for, so some tinkering is required to optimize the air/fuel ratio.
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duster97
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Re: High Hydrocarbons / deq and idle issues!!

Post by duster97 »

My brake fluid is defiantly full. I haven't bled anything since I bought it a month ago. Been working on this deq stuff. I'm at work right now but when I get home I plan on getting some hoses and running some vacuum lines according to the advice from the thread that was posted. Maybe I need a new break booster? I'll check the lines when I get home for leaks. I won't need to run a new pcv line since I didn't have to remove the spacer under the carb to fit the air cleaner. I just need the charcoal canister lines put back in it appears. And the intake and advance lines. All that stuff.
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Re: High Hydrocarbons / deq and idle issues!!

Post by dlb »

if your brake fluid is good, the problem is in the brake fluid cap, the park brake button, or the wiring for either. should be easy to figure out which it is. a bad brake booster would not make the brake light come on. besides, if the booster was bad you would know it because you would have very little braking power.
duster97
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Re: High Hydrocarbons / deq and idle issues!!

Post by duster97 »

Yah my booster is not bad. Checked the hose as well by taking it off and plugging it with my thumb. Made the engine vibrate alot and run rough with it unplugged, so I came to the conclusion the booster isn't bad or leaking.

As far as deq goes I re installed two vacuum lines one to the carb and one to the upper advance. I retarded the dist all the way I could. Ran gutless. Took it to deq. My hc passed at idle, but was like 60 ppm too high at 2nd idle. I drove the thing for like 40 mins before going too. My co levels went up with the retarded timing however and were not within parameters. Still trying to find that sweet spot with my timing and air fuel mixture. Kinda frustrating, but I'm going to go buy a compression test kit today and see how it goes.

When I unplug the 4th spark plug wire I can hear and feel the tiniest difference in engine running, like it does make a difference, but it's very very small. I switched the 3rd and 4th cylinder plugs on the dist to to see if it was a wire. Hopefully the compression test goes well. I hope it's not a lower end problem.

Here in oregon I guess you can transfer plates between cars for like 5 bucks, so if I can't get this thing to pass my roomate has a kia that he doesn't use with good tags that he will sell me the plates and I can just transfer the plates to my tercel
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