I don't have a s-afc. If his problem is the same as mine (might not be but sounds like it) then it's not that the af readings are bouncing around, its the motor runs rich overall after a restart.
Constant Adjustment of A/F Levels
- Thread starter supraguy31
- Start date
thats possible too, however, in his post he said that with the motor running rich, he would lean it out on the low throttle map (a big no-no) and then it would go back to where it was before.
Shut off & restart= car runs rich, compensate by leaning mixture. Get home, car sits overnight (or until coolant cools all the way down) then the car runs fine so you have to richen the mixture to where it was before you leaned it out. As long as you never shut the car off warmed up & then restart= everything ok.
Buddafucco said:
Start Engine first time in morning engine Idles and Cruises at 14.4 to 15.0 runs great, I can drive it for a Hour and the A/F ratio wont change until I shut it off.
Shut car off, Immediately Start back up..... A/F drops to 11.5 to 12.8 and normal driving is same range. Lean it out with SAFC (-18 or so at 1000 and -22 or so at 2000) until It reaches 13.6 or so on Wideband monitor. Done for the Day.....
Next morning, Turn car on and it runs like total shit until I turn the low throttle maps back to the 0 position on the SAFC, Once back to 0, Purs like a Kitten and runs great
Repeat next day and so on........ Again, Problem only started when I went to a V-Band type setup with sensors that close to the Turbo. Before then, I never had this Problem and I was using the same Wideband sensor then.
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Doward said:
PowerDex does and most onboard standalones do.
Never said the 02 positions were the root cause just that they're in the wrong place and aren't going to last long there.
It's a pity no aftermarket WBs are using newer wideband sensors such as the Denso A/F sensor, shown in the factory position on my 2GR-FE. It needs to be hot (1200F) to work, and the powerful factory heater allows operation 10s after cold start.
Attachments
3p: Most WB sensors are original equipment at Crematoriums 
(I'm serious)
And this is why they don't cope all that well in an automotive application.
I'm guessing that Denso is designed for the job it's doing?
(I'm serious)
And this is why they don't cope all that well in an automotive application.
I'm guessing that Denso is designed for the job it's doing?
They are Picking up the Bungs today so they can do the welding up in the morning. I just Poped a code 21 while Driving so its a good thing Im going to move them Down stream.
Code 21..... Detection of Oxygen Sensor Detrioration (Oxygen Sensor Signal)
To close and too dam Hot.
Robert
Code 21..... Detection of Oxygen Sensor Detrioration (Oxygen Sensor Signal)
To close and too dam Hot.
Robert
You know code 21 just means that either the factory O2 sensor heater is open circuit, or its not cross counting during closed loop operation. Given you just replaced it, it should be obvious that the problem is not the sensor. The TCCS knows nothing about your wideband, so it will not set a code because the WB is too hot, or any other issue with it.
Try looking for leaks in the exhaust as JJ said in post #4.
Try looking for leaks in the exhaust as JJ said in post #4.
Only pops the Code when Im under Boost, Any other time I dont see it. If you remember earlier in this tread, I mentioned that I got a code once before and that was when I was under boost also.
Im using a O2 sensor from the Ford Mustang since its the 3 Wire O2 sensor that you all recommended as a Aftermarket replacement. If there is a Better one, Please someone let me know.
Im using a O2 sensor from the Ford Mustang since its the 3 Wire O2 sensor that you all recommended as a Aftermarket replacement. If there is a Better one, Please someone let me know.
It sounds like to me you have a tuning problem...follow MmmBoost instructions or find someone that knows what there doing if you don't know what he is talking about.
Sorry about that.
Well, Everything has been moved back a good 3 feet away from the turbo as the AEM Manual said. this is what Im getting now and Its pretty close to the Exact same thing as before.
Start the car up and It Idles correctly but when you Start to Drive it, It starts out running lean until the Temp Increases. Its like the warmer it gets, the A/F compensates and starts to richen up. Now once the Temp is up to normal and Im at a 60mph cruise It reads 14.5 or so.
Now here is the funny part of all this. Without stopping the car or Accelorating (ie Still at a Steady cruise) The A/F ratio will continue to drop into the Rich area very Slowly. Its like Im cruising and its showing 14.6, then 2 Minutes later its showing 14.3, then a minute or 2 later its showing 13.8 to 14.0 and so on and so on until I reached the 12.5 area. It just continues to go richer and richer with every mile I drive.
I ordered a New Wideband Sensor and it will be here on Monday. I just cant figure this out as Ive done everything that the Manual has stated so far. Only other thing I know to do is get another sensor as this one might be toast once it gets hot, Replace the Narrow band one Again or go to a Different Wideband setup.
Any Ideas?
Robert
Well, Everything has been moved back a good 3 feet away from the turbo as the AEM Manual said. this is what Im getting now and Its pretty close to the Exact same thing as before.
Start the car up and It Idles correctly but when you Start to Drive it, It starts out running lean until the Temp Increases. Its like the warmer it gets, the A/F compensates and starts to richen up. Now once the Temp is up to normal and Im at a 60mph cruise It reads 14.5 or so.
Now here is the funny part of all this. Without stopping the car or Accelorating (ie Still at a Steady cruise) The A/F ratio will continue to drop into the Rich area very Slowly. Its like Im cruising and its showing 14.6, then 2 Minutes later its showing 14.3, then a minute or 2 later its showing 13.8 to 14.0 and so on and so on until I reached the 12.5 area. It just continues to go richer and richer with every mile I drive.
I ordered a New Wideband Sensor and it will be here on Monday. I just cant figure this out as Ive done everything that the Manual has stated so far. Only other thing I know to do is get another sensor as this one might be toast once it gets hot, Replace the Narrow band one Again or go to a Different Wideband setup.
Any Ideas?
Robert
I have Reset the ECU already but I havent unplugged to SAFC. Wouldnt that Affect the VPC since the SAFC is wired into it. If not then I will try that and see what it does.
Robert
Robert
Well, I just installed my New Wideband Sensor today. Absolutely no change in what the car is Doing. Still reading the say way as I said in the Above Post. I dont know what the hell is going on here.
I pulled the AEM controller and made sure that the settings were in the correct Spot. Turned the Key on but didnt start the engine and it goes through the Test Phase then it ready 16.0 on the Gauge. Started the car and just let it Idle and it Idled at 15.7 to 16.3 Waited for it to get to Normal Operating temperature and then Shut it off. Now after Shutting it off, I turned the Key to the on Position but Dont start the car, The wideband goes through its test Phase but then all of a Sudden reads 13.4 and the motor isnt even running. Start the car and it reads 10.5 to 12 when I press the gas.
So Im really confused now. this is with the new Sensor and all.
Help me someone Help me
Robert
I pulled the AEM controller and made sure that the settings were in the correct Spot. Turned the Key on but didnt start the engine and it goes through the Test Phase then it ready 16.0 on the Gauge. Started the car and just let it Idle and it Idled at 15.7 to 16.3 Waited for it to get to Normal Operating temperature and then Shut it off. Now after Shutting it off, I turned the Key to the on Position but Dont start the car, The wideband goes through its test Phase but then all of a Sudden reads 13.4 and the motor isnt even running. Start the car and it reads 10.5 to 12 when I press the gas.
So Im really confused now. this is with the new Sensor and all.
Help me someone Help me
Robert
One trick that helps is to use the blue wire (normally for MAF Voltage input) and hook it up to the Vf output pin on the ECU. That way, you can see if the ECU is happy or not just by going into The ETC... Sensor Check option on the SAFC.
Vf:
0 volts: full rich
1 volt: rich
2-3 volts: OK
4 volts: lean
5 volts: full lean
When driving around, this number should stay at 2-3 volts. If not, the ECU IS making changes by itself! The idea is to work with the ECU, still trick it some, but also cooperate at the same time.
Ok, I did some looking around and I took a chance at my VF Readings. Once I start the car up in the morning and let it warm completely up (5 Minutes) I check my VF signal and it reads .8v to .9v, Now if I turn the car off and switch it right back on, the VF signal jumps to 2.19 and this is when the A/F ratio goes really rich. The VF doesnt change regardless. I talk to a friend of mine and we went through everything. This is what we came up with and I hope you all Agree.
Fuel System.. MKIV TT Fuel Pump at consistant 12V
FPR... Stock Fuel Presure Regulator
Injector Size... Stock 440s
Turbo... 67mm
Was told that my Biggest problem is the Stock FPR with a MKIV Pump. I also had to running through the J-Tube which might be increasing the FP also.
Any Ideas or Comments.
Robert
Vf:
0 volts: full rich
1 volt: rich
2-3 volts: OK
4 volts: lean
5 volts: full lean
When driving around, this number should stay at 2-3 volts. If not, the ECU IS making changes by itself! The idea is to work with the ECU, still trick it some, but also cooperate at the same time.
Ok, I did some looking around and I took a chance at my VF Readings. Once I start the car up in the morning and let it warm completely up (5 Minutes) I check my VF signal and it reads .8v to .9v, Now if I turn the car off and switch it right back on, the VF signal jumps to 2.19 and this is when the A/F ratio goes really rich. The VF doesnt change regardless. I talk to a friend of mine and we went through everything. This is what we came up with and I hope you all Agree.
Fuel System.. MKIV TT Fuel Pump at consistant 12V
FPR... Stock Fuel Presure Regulator
Injector Size... Stock 440s
Turbo... 67mm
Was told that my Biggest problem is the Stock FPR with a MKIV Pump. I also had to running through the J-Tube which might be increasing the FP also.
Any Ideas or Comments.
Robert
Stock FPR is designed to work with the stock pumps flow rate. If you fit a larger pump with a higher flow rate you will get alot more fuel pressure. Do you have a pressure gauge?? I would hazard a guess that with 12v constant to the pump you will be up around 50psi at the rail. I have a Walbro GSS341 with my modified stock fuel pressure regulator I can't get my fuel pressure below 38psi at 9v. I'm in the middle of getting a SARD FPR.