AFC idle issue

I put the 440cc's back into the car as it makes the gasket sit tighter.

Just buy some throttle body cleaner and spray near your injectors, if the RPM changes, you need new insulators. If not, spray everywhere until you find the leak.

Ya thats what I will do with some brake cleaner! Ill let you guys know!
 
Ya thats what I will do with some brake cleaner! Ill let you guys know!
Brake cleaner will eat rubber and plastic parts...dont use brake cleaner.
Now Carb cleaner is what I have seen used for ever and will not et all of the plastic.
This is what I suggest using.
 
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Brake cleaner will eat rubber and plastic parts...dont use brake cleaner.
Now Carb cleaner is what I have seen used for ever and will not et all of the plastic.
This is what I suggest using.

Lots of people seem to be using brake cleaner as well, but thanks for the tip. Can you fin carb cleaner anywhere like at Walmart? Whats is carb cleaner make for by the way? Cleaning up carbon deposits?

Thanks
 
Lots of people seem to be using brake cleaner as well, but thanks for the tip. Can you fin carb cleaner anywhere like at Walmart? Whats is carb cleaner make for by the way? Cleaning up carbon deposits?

Thanks
Ummmm...Cleaning Carberautors.

its very similar to brake cleaner, just not as strong. i think
Not the same..GO ahead and start spraying Brake cleaner around your engine bay....Lets see what kind of problems develop.

This could be a fun game.
 
Bump. Did you figure out what the problem was? I'm having the same problems running lean at idle. It starts out normal but slowly goes to 18 and then the car tries to stall.
 
check your bov's i was having the same problem as you guys, at first i thought it was the afc. But i changed my bov, I had a greddy type s and i put on a greddy rs, and i haven't had the code return yet and i no longer run lean.

I took the greddy type s apart and it had a huge rip in the diaphram, I'm assuming it was leaking too much for the car to compensate and it was going too lean.
 
Bump. Did you figure out what the problem was? I'm having the same problems running lean at idle. It starts out normal but slowly goes to 18 and then the car tries to stall.

I tighted every possible clamps, but havent got to check with the brake cleaner yet! My car is running much better since I changed the O2 sensor tough. It is still a bit lean for a few seconds when I idle and then starts to oscillate back and forth which is the normal behavior and that is with the AFC plugged it. Sometime it still wants to stall a tinny bit, but the CEL is gone so my guess is that it is my EGR valve or a small leak somewhere. For now, I can live with it and will try to figure it out more whenever I have some free time.

My new O2 sensor is working pretty well tough even if it is a generic one from Mazda. A lot cheaper (only 100 $CAN) and from what I read its gonna get paid by itself because I am gonna have a much better A/F ratio for now long so the economy on gas will eventually pay for it.

So for now I am a happy camper, but will still check deeply whenever I have the time for a leak and maybe also clean up my EGR valve.

You should start looking for a leak as it is mostly that (or clean up your EGR valve), if not you can change your primary O2 sensor. Even if this is not the problem you still get better mileage!
 
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I tighted every possible clamps, but havent got to check with the brake cleaner yet! My car is running much better since I changed the O2 sensor tough. It is still a bit lean for a few seconds when I idle and then starts to oscillate back and forth which is the normal behavior and that is with the AFC plugged it. Sometime it still wants to stall a tinny bit, but the CEL is gone so my guess is that it is my EGR valve or a small leak somewhere. For now, I can live with it and will try to figure it out more whenever I have some free time.

My new O2 sensor is working pretty well tough even if it is a generic one from Mazda. A lot cheaper (only 100 $CAN) and from what I read its gonna get paid by itself because I am gonna have a much better A/F ratio for now long so the economy on gas will eventually pay for it.

So for now I am a happy camper, but will still check deeply whenever I have the time for a leak and maybe also clean up my EGR valve.

You should start looking for a leak as it is mostly that (or clean up your EGR valve), if not you can change your primary O2 sensor. Even if this is not the problem you still get better mileage!

Update:
My car is still running lean and stalling sporadically. The past days were better because my A/C was practically always on so the idle was always a bit higher so the car was running better.

EGR seems very plausible, but apparently its a pain to remove it because of the restrictive space so I will see what I will do.
 
I was reading this too just now, and i picked up on a change that im not sure if it is the difference in the V1 and V2 used, but under the settings for Output Settings, the "PWM Mode" was set to 0-30psi/3vdc FS, and in the stock supermap that i downloaded from here, it was set to 5vdc FS, i still haven't extracted the map from my afc to compare, and im not sure the difference in settings if that makes a difference, but im guessing it might.. hopefully someone from the original thread will post something about this.
 
I was reading this too just now, and i picked up on a change that im not sure if it is the difference in the V1 and V2 used, but under the settings for Output Settings, the "PWM Mode" was set to 0-30psi/3vdc FS, and in the stock supermap that i downloaded from here, it was set to 5vdc FS, i still haven't extracted the map from my afc to compare, and im not sure the difference in settings if that makes a difference, but im guessing it might.. hopefully someone from the original thread will post something about this.

Do you have any infos on that, because I still have the same lean problem at idle... and it is starting to bug me a bit hehe!

Anybody else with the same problem by the way?
 
not much, i found out after that it is the 3vdc and not the 5vdc, i guess it had changed at some point but lately my idle has been pretty good, around 700 i think (first actual bar is 500rpm right?) but it dips down and catches itself here and there but nothing too bad, i think with other idle issues that people have has to do with the O2sensor maybe being a little clogged since it runs normally really rich and shows in the exhaust being really black all the time lol, but either that or the egr maybe instead so much for the AFC, but that might be true for some people, but I can't think of much else so far, i noticed also that when you have better dedicated vac. lines like the solo line going to the wga, and the vac lines coming off the BB line it runs a little better... other than that i dono.. i haven't really had to much time to play around with it..(school work is killing me)
 
I've got the same problem too.

I've got a Wideband and at startup it'll run down to 18 where the CEL will come on p0171 running lean.

but once warmed up all is good.

i think I also have a vac leak on the little silicone hose that comes off the afc, stupid thing is soo thin I've caught it binding on itself a couple of times.

what is the best way to clean a o2 sensor?
 
I think i remember someone saying they used like break cleaner or something like that.. or possibly a egr cleaner or something, i would double check with autozone or something like that..

and ya i know what you mean about that small vac line coming off of the afc, i made sure mine was rounded and not bending at all anywhere, and i also used some electoral tape to support the hoses connecting so there wasn't such a sharp ending after the connection. if that makes and sense.
 
i've got wire loom on it now which prevents it from bending in sharp angles along the hose but where the hose goes into the box usually gets bent.
 
ya i just have it looping around, and the tape with the connector helps it so it doesn't bend so sharply, I would suggest trying to just take some electoral tape (has some "body" to it) and just tape it along either end of the connector and just tape it along the rubber tubing from the afc side so it supports the tube a little better and gives it a little more sturdiness to it.. and it shouldn't bend so much at the afc connection part, if i can get a pic of it sometime soon ill post it up to show you what i mean.
 
Something else to check, not sure if it was posted, is the egr nut on the Exhaust Mani. I know someone who was having leaning out issues with teh afc and he recently discovered that his egr nut was on ther but not all the way. it will cause it to lean out. I guess the nut side gets stripped out easy so make sure its really, really tight.
 

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