Question is, whats your commanded AFR than?
Dh a/f accuracy.
- Thread starter laloosh
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Question is, whats your commanded AFR than?
my commanded at idle is 14.2 and thats what actual is. Ken over at msd suggested that the a/f ratio is also dependant on the cat temps. NOw that i think about it i have that cheap spark plug fouler mod that removes the 2nd o2 from the stream in order to eliminate the p0421 code....i wonder if htat has anything to do with it.
Exactly, they are all 6's... Which leads me to believe, although the car is seeing a high AFR, the computer is doing something to keep the engines from blowing. what its doing is unclear, but something is happening.
Maybe its time to get all of the DH guys to start logging timing, cmd afr, oem afrs and rpm. We can start a new thread with this data. Maybe our cars are doing different things across the U.S.
Is the wideband at the top of the exhaust manifold in the middle of the heat shield if you were looking at the top portion of the engine?
So you tricked the primary 02 that is under the car somewhere towards the pre-cat which is in the upper neck region of the DP? There should be an additional 02 that follows after the primary cat that would be triggering the CEL. Its basically just a 02 sensor that reads a set heat index. That is the one you usually trick when going with race pipes, not the primary 02. Its a resistor with a diode that plugs in the connector.
I havent put a lot of time into looking at the under side of the car because its such a pain in the ass to get on ramps. So, if there are a total of 3 O2 sensors, the last one if the one you need to put that mod on. From my experiences with Fords, you have 2 02's for each side of the exhaust. The CEL Eliminator plugs connect to the rear most 02 sensors, not the primaries.
Spark plug fowler mod.. what is this? Same thing as a CEL Eliminator? I need more info on your mod and if its something you constructed on your own or something bought and tested that eliminates CELs on the 02 sensors. We may be finding the source of your problem right here.
The car has 2 o2 sensors. The main one is in the downpipe btwn the primary cat and the turbo. This is the wideband sensor. The second sensor is in the downpipe after the primary cat. This is the sensor that is slightly pulled out of the stream.
Spark plug non fouler mod is basically two spark plug non foulers that screw into each other and into the stock location. This acts like an extension which just removes the sensor from the stream and lowers the values it reads thus eliminating the no cat code.
Spark plug non fouler mod is basically two spark plug non foulers that screw into each other and into the stock location. This acts like an extension which just removes the sensor from the stream and lowers the values it reads thus eliminating the no cat code.
Hmm, well i dont see that as your problem unless mazda is actually pulling data out of that sensor which i cant see being the case. That sensor is only used for OBD-II complance to report the converter not operating correctly due to heat measurement. All a MIL Eliminator does is takes a resistor and a diode, wraps it into an 02 sensor connector and tricks the output to whatever voltage the ecu is looking for in normal operating conditions. I think its 3 volts but im not 100% sure. You have done the same thing by taking the sensor out of the direct path of the exhaust, allowing for the temp difference.
Here is a datalog of a quick run I did on the way home yesterday.. ambient temps were 30 degrees F .. far cry from the -25 we were seeing a couple weeks ago, but the data was the same... I have never seen my afr's or commanded afr's in the same range during boost as Laloosh is showing in his datalogs..
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Thanks Chris, that was what i was trying to gather. My car doesnt do what his is doing either. It might be a possibility his wideband is dying out too. Several people had to have theres replaced under warranty.
I can do some logs on my way home, just one question though. I just got my Dashhawk last week and am still learning all the parameters. I know which to use for CMD AFR, RPM, and OEM AFR, but TIMING? which do I use for that? (Sorry if this is a stupid question)
Thanks, I found it. I'll do a couple logs on the way home, plus I have to run to Tacoma later so I can get a couple pulls on the highway too. So Laloosh and/or Haltech, would you like to see those 4 parameters? (rpm, cmd afr, act afr, and spark advance) Or are there others?
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ok heres my idea. The rear o2 sensor monitors the cat. If there is no cat, the car will throw the p0420 code which mean the rear o2 sensor is picking up too much fuel being that the cat is not doing its job. now if u take the rear o2 sensor out of the stream it will read very little of the actual fuel and it will relay a lean condition to the ecu and in return the ecu commands more fuel?
My assumption is the ecu will believe the readings of the more noble sensor. The narrowband should not be able to over ride the wideband, right?
its not reading fuel big dog but rather heat. Those rear o2's are for one purpose, failure of the main converter. If the converter fails, the heat going down stream from the sensor is lower and thats when it throws the CEL. Think of a catalytic converter as a ceramic oven. ITs main job is to trap unburnt fuel and stuff and heat it up so it burns. The ECU in closed loop mode ( WOT ) will compare the measured air/fuel ratio to the target air/fuel ratio and automatically increase or decrease fuel delivery accordingly. In open loop ( Idle/Part Throttle ) mode, the ECU will still use the oxygen sensor to read air/fuel ratios, but will not adjust fuel delivery as in closed loop mode. What does this mean? The Wideband is the main 02 sensor in our car as we dont have a narrow band
this car is pissing me the **** off. im a **** hair away from trading it for an 04 s2000(argh)
some1 needs to explain to me why my a/f ratios dont follow commanded a/f ratios despite no loss in fuel pressure and no increase in injector pw. The car knows its not following the desired and its not doing s*** to even try.
some1 needs to explain to me why my a/f ratios dont follow commanded a/f ratios despite no loss in fuel pressure and no increase in injector pw. The car knows its not following the desired and its not doing s*** to even try.
It is complex, not a pos. lol. It will do great things in the hands of Cobb...I hope. Hold out till cobb.
