[grovedogg]

I need a little advice from all you Toyota (and non-Toyota) guys out there.
My Runner has failed, everything looked good except the carbon mono.
Testing as a gross polluter.
The tech told me that there is a "fuel control problem" no idea what he means. Anybody have an idea? I tested the EGR among others which turned out fine.

[Billy D.]

the only ones I can think of are Throttle position sensor, Idol air control sensor, or O2 sensor good luck

[toyoder]

DO YOU HAVE A CHECK ENGINE LIGHT ON ? LOOK AT THE TPS AND O2 AS BILLY SAID

[grovedogg]

No check engine light... Is there a TPS and O2 sensors on a carbbed engine?
I was thinking it would it have something to do with the carb itself...?

[tfpets]

"Fuel Control Problem" is a very vague term describing just about anything in the fuel system...High CO is going to be a rich condition that can be any number of things, especially in a carb system...it should also be high on HCs as well if the CO is high enough to be a gross poluter...there are so many things to check on that I dont know where to start! If it were in front of me I could give you some opinions though!

[toyoder]

oh forgot you were carbed i think you still should have a o2 sensor . we used to have a 84 runner carbed and had problems smoging it one year cause it wasn running way to rich tryed to drill out the side of the carb to make a adjustment on the factory lean rich settings but didnt make a differance ended up buying a carb from auto zone around $275 ouch this was at least 5 years ago im sure there even more now

[grovedogg]

well here is the test...
test 1: 1k RPM
HC
41 (max is 150) PASS

CO
.02 (max is 1.2) PASS

test 2: 2,500 RPM
HC
203 (max is 180) FAIL
(gross pollute is 330)

CO
3.59 (max is 1.2)
(gross pollute is 2.7) FAIL

it is high on CO. when i bought it the high idle didn't work. I cleaned the carb (without removing it) with ... can you guess... "carb cleaner" .. sorry... had to raise my spirits... anyway ,the high idle came back and ran a whole lot better. Another important tid-bit ... the runner idles right around 1,100 RPM. it passed the idle test, but 2,500 ran really rich.

thanks guys for the quick posts. I have to get this figured out b-4 the 22nd.

This post has been edited by grovedogg: 31 August 2009 - 08:40 PM

[Billy D.]

you also may want to have the cateletic converter checked

[76 Patriot]

I had a similar problem with a (Mikuni) carb'd Ram-50. The garage told me they would have to hook it up to diagnostics for the small fee of $75.00, even though the printout recommended an adjustment to the fuel/air mixture.

I told them I wasn't going to pay $75.00 to have a machine confirm that it needed the mixture screw adjusted, so they labeled it a gross poluter. By doing this they became the only station that could re-test the vehicle (I found this out because I took it to a different shop and they confirmed all it needed was an adjustment, but they couldn't test it because it was in the system as a GP from the other station), and they refused to re-test it without the diagnostics.

I never went back there. Of course, that was over 10 years ago.

Any of this sound familiar?

[xj4life2]

It appears as if the air pump is not comming on (HIGH CO'S) check to be sure the air pump is working, it is controlled by the o2 .

PS tfpets was dead right "fuel control " is a blanket statement

This post has been edited by xj4life2: 01 September 2009 - 01:28 PM

[jdaudio12]

Billy D., on 01 September 2009 - 03:12 AM, said:

you also may want to have the cateletic converter checked

thats what i was thinking also. a good thing to do be for smog is get the cat realy hot be for geting there.

[tfpets]

Honestly though the cat wont be able to bring the CO down that far and it would probably be higher at idle if it wasnt working...the carb is dumping way to much fuel off idle...this is not a mixture adjustment or anything like that...it could be the MC (mixture control) solenoid is not working...this solenoid is controlled by the computer to adjust the mixture from rich to lean, like changing injector pulse on an EFI system...if it quits it goes to a full rich position...it is possible to get the idle to pass with this condition but there is nothing you can do to make it pass off idle...

[rsc71]

tfpets, on 01 September 2009 - 04:01 PM, said:

Honestly though the cat wont be able to bring the CO down that far and it would probably be higher at idle if it wasnt working...the carb is dumping way to much fuel off idle...this is not a mixture adjustment or anything like that...it could be the MC (mixture control) solenoid is not working...this solenoid is controlled by the computer to adjust the mixture from rich to lean, like changing injector pulse on an EFI system...if it quits it goes to a full rich position...it is possible to get the idle to pass with this condition but there is nothing you can do to make it pass off idle...

after reading all these responses i have to say i love my pre 75 toyotas:)

[grovedogg]

rsc71, on 01 September 2009 - 05:44 PM, said:

after reading all these responses i have to say i love my pre 75 toyotas:)

yeah, yeah... LOL

I will check the air pump, and check the carb. I also think I need a valve job, there is a slight valve chatter around 2000 RPM. would needing a valve adjustment be anything to do with the smog?

[FJ40Rob]

grovedogg, on 02 September 2009 - 06:44 PM, said:

yeah, yeah... LOL

I will check the air pump, and check the carb. I also think I need a valve job, there is a slight valve chatter around 2000 RPM. would needing a valve adjustment be anything to do with the smog?

I have to say that all this technical stuff about Smog's is confusing to say the least. I was'nt sure my e-350 Van was going to pass Smog? It was running rich and used a lot of gas we asked around about this and got now where with it so we made an appointment at Tom's Glass and Muffler in Red Bluff on main street and said can you do a pre Smog so it wont be a Gross Polluter we told him that it ran rich the tech said it would cost an extra $20 so my Wife said go ahead and do that.. We got the van back and it passed A little tweakin on his part and where good to go. The moral of the story is go get your self a bottle of GUARANTEED TO PASS it's a fuel cleaner and run your rig at 70 + and go get it Somged and don't forget to let your Wife take it in and say it run's rich I don't know what to do

[76 Patriot]

FJ40Rob, on 03 September 2009 - 07:30 AM, said:

I have to say that all this technical stuff about Smog's is confusing to say the least. I was'nt sure my e-350 Van was going to pass Smog? It was running rich and used a lot of gas we asked around about this and got now where with it so we made an appointment at Tom's Glass and Muffler in Red Bluff on main street and said can you do a pre Smog so it wont be a Gross Polluter we told him that it ran rich the tech said it would cost an extra $20 so my Wife said go ahead and do that.. We got the van back and it passed A little tweakin on his part and where good to go. The moral of the story is go get your self a bottle of GUARANTEED TO PASS it's a fuel cleaner and run your rig at 70 + and go get it Somged and don't forget to let your Wife take it in and say it run's rich I don't know what to do

I'm sure the extra $20.00 helps, too.

[grovedogg]

tfpets, on 01 September 2009 - 04:01 PM, said:

Honestly though the cat wont be able to bring the CO down that far and it would probably be higher at idle if it wasnt working...the carb is dumping way to much fuel off idle...this is not a mixture adjustment or anything like that...it could be the MC (mixture control) solenoid is not working...this solenoid is controlled by the computer to adjust the mixture from rich to lean, like changing injector pulse on an EFI system...if it quits it goes to a full rich position...it is possible to get the idle to pass with this condition but there is nothing you can do to make it pass off idle...

I had a local shop here in Redding look at the Runner. The tech told me the carb needs to be re-built, the air diverter valve and the cat need replaced. I agree with your statement that the cat wouldn't bring the CO's down that far. Any ideas on possible aftermarket carbs and your exp. with them.?

[grovedogg]

Is there another name for an "air diverter valve"? I have searched the FSM as well as the web and haven't found much. Could it be called the "air control valve" or something else?