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Discussion Starter #1
I have just replaced my head, put in Farrea valve train, HKS 264 cams, new exhaust, new 02 sensor, new temp sensors, etc.... It seems that my car was running rich to begin with (before these mods). But now it runs really rich, IE my O2 meter is pegged at rich, the car smokes due to cylinder wash down. The car runs great. I have no power loss and compression checks are good. I think I am just getting to much fuel. I have a HKS Super AFR installed but it has been bypassed due to the fact the car won't start with it hooked up unless it is warmed up. Any help will be greatly appreciated.. Thanks in advance!!!
 

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^Obviously, the main O2? Since you feel you need to bypass the SAFR you probably are looking at that as being your culprit. Are you familiar with the SAFR settings? If not, it's easy to fool the ECM into a different section of the map. I would first check your eRPM and confirm that the SAFR is reading accurate.
 

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Discussion Starter #4 (Edited)
I replaced the O2 sensor that is by the transmission on the exhaust. I have a RMM down pipe and no cat. The AFR when plugged in, gives a good RPM signal. Could it be MAF??? At the risk of sounding stupid, is there another 02 sensor that I ahve missed?
 

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^Yes, there is another O2 but this one is mainly for catalyst protection. If the MAF is suspect you should still be able to run fairly well (A/F-wise) since default values will take-over. Since you have the SAFR out of the loop and it still runs rich, must be something else. You had the head off so begin double-checking hose connections I guess. Several conditions must be met for a code to register for A/F too rich. Can I assume that this condition is only at idle??
 

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Discussion Starter #6
Yes this is only happening at idle. It acts like the car is loading up. If I let the car idle for a few seconds it will start smoking. Then step on the throttle and rev a couple of times. It will clear for a few moments. I have been told that smoke can be seen when shifting. Thanks!
 

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Boost4fun
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I replaced the O2 sensor that is by the transmission on the exhaust. I have a RMM down pipe and no cat. The AFR when plugged in, gives a good RPM signal. Could it be MAF??? At the risk of sounding stupid, is there another 02 sensor that I ahve missed?
Wait a sec. Which one do you mean? Is it the one at the end of the tranny right underneath the gear switch? If yes this one will not affect your AFRs at all. The primary O2 sensor is close to the turbos BEFORE the DP begins. It is vera hard to see and even harder to get by when everything is installed. This one will affect your AFRs and could be the culprit if shot. If you have a narrowband display connect it to the appropriate pin at the ECU and check out the readings. If it tells you a too lean mixture it´s def gone and need to be replaced.

Gerd
 

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^Right. If you replaced the sub O2, you hit the wrong one. A drifting A/F only at idle is a sure sign that the main O2 is tired.
 

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Boost4fun
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Yeah, let us know.
 

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Discussion Starter #11
Replaced front O2 sensor. Less smoke but still there. I am going to put the car on a 5 gas analizer next week. I have a bypassed HKS super AFR. When I remove the bypass and plug it in when the engine is cold, the car will not start. Smells like fuel. If I plug the AFR in when the car is warm it seems to have better throttle response but no effect to smoking at idle or revving with no load??? Dont want to run the AFR without dinoing the car... Stay tuned!
 
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