Lean
07-24-2004, 09:06 PM
#1
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Re: Best Bang for the $$, exterior 'upgrades' ??
After i do about an hour of just normal driving the car gradually pulls me extremely LEAN. I have checked out all the fuel components and everything is working great.
In order to get the car out of the lean "mood" all i have to do is reset the ECU and then i am fine for a little while but the car will always pull itself lean. Now i noticed that if i reset the ecu and just drive the car FULL throttle all the time the car wont pull me lean. Its only when i am doing normal driving that the car will pull me lean.
Also when the car gets in the lean mood it doesnt not matter how much i increase the fuel on the SAFC or increase the fuel pressure on the FPR the car still be lean. I have even tried plus 50 % on the safc and i am still lean.
Just wondering if you could give me some idea's on what check for would a o2 sensor that is bad do this?
450 cc injecotrs
SAFC
AEM FPR
In order to get the car out of the lean "mood" all i have to do is reset the ECU and then i am fine for a little while but the car will always pull itself lean. Now i noticed that if i reset the ecu and just drive the car FULL throttle all the time the car wont pull me lean. Its only when i am doing normal driving that the car will pull me lean.
Also when the car gets in the lean mood it doesnt not matter how much i increase the fuel on the SAFC or increase the fuel pressure on the FPR the car still be lean. I have even tried plus 50 % on the safc and i am still lean.
Just wondering if you could give me some idea's on what check for would a o2 sensor that is bad do this?
450 cc injecotrs
SAFC
AEM FPR
07-24-2004, 09:44 PM
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Re: *SPLIT* LED stuff
im not sure if a o2 sensor would cause this to happen. the fact that it gradually changes is whats weird. anyway, it wouldnt hurt to check this out...
http://hmaservice.com/webtech/iindex.asp?i...0620#_394880620
http://hmaservice.com/webtech/iindex.asp?i...0620#_394880620
07-24-2004, 10:36 PM
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Re: *SPLIT* LED stuff
I'm not sure about with the SAFC, but I was reading that with the stock ECU if you are below like 60% or something of full throttle you are in closed loop mode. Which means that the computer uses the O2 sensor in the exhaust to regulate how much fuel to inject.
Once you go full throttle though it goes out of closed loop and follows the map points for fuel air ratios that are stored in the computer. Pretty much ignoring what the O2 sensor in the exhaust side has to say.
So assuming I'm remembering it right and given what you have said I would say there could be something wrong with the O2 sensor in your exhaust before the catalytic converter.
Although as tibby01 says, the fact that it changes gradually is bizarre.
Hope that helps.
Once you go full throttle though it goes out of closed loop and follows the map points for fuel air ratios that are stored in the computer. Pretty much ignoring what the O2 sensor in the exhaust side has to say.
So assuming I'm remembering it right and given what you have said I would say there could be something wrong with the O2 sensor in your exhaust before the catalytic converter.
Although as tibby01 says, the fact that it changes gradually is bizarre.
Hope that helps.
07-24-2004, 11:25 PM
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Re: Insomniac Thread
Yeah, I have been talking to Gary trying to figure this out. And it seems that the ECU is learning the curve and correcting back to normal.
I myself have never had a problem like this and have been running the SAFC in my car for about 6 weeks and mine is fine. I was thinking that the o2 was the cause but I have never seen a bad o2 not throw a cel.
:? :? :? :? :? :? :?
I myself have never had a problem like this and have been running the SAFC in my car for about 6 weeks and mine is fine. I was thinking that the o2 was the cause but I have never seen a bad o2 not throw a cel.
:? :? :? :? :? :? :?
07-24-2004, 11:29 PM
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Re: Lean
dude
i got my car dyno'd and my car is running really lean. I have the mods below. And i am changing that sensor in the downpipe of the Headers(exaust manifold) tommorow and also receting the ECU.
i got my car dyno'd and my car is running really lean. I have the mods below. And i am changing that sensor in the downpipe of the Headers(exaust manifold) tommorow and also receting the ECU.
07-25-2004, 12:07 AM
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Re: Stuck in 3rd gear
How lean are you going, it's normal to run kinda lean under normal driving while in closed loop, under normal driving on the highway my A/F ratio is at about 14.6-15.7 and this is normal, at full throttle at 12psi I'm at about 12.5-13.0.
07-25-2004, 08:28 AM
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Vehicle: 2000 Hyundai Tiburon
Re: Members
when the car goes lean, it stays lean. When i go full throttle the air/fuel richens to about 14-13 then takes a dive down to 16 8O . I have no idea whats going and need to get this fixed fast because i havent been able to drive it for over 6 weekds normally because of Detination.