Dh a/f accuracy.

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.

But it is trying. There is that one initial jump where the afr goes way up, but as the commanded AFR goes down, the actual is following it, but there is that damn gap between the two. So either we are missing something with regards to the sensors and the Dashhawk is being fooled and showing bad data, or something is preventing the actual AFRs from getting to the commanded level. The command level keeps going down (to ridiculous lows IMO) and the actual is trying to get there but can't.
 
Here's a couple I did tonight. Hope they help.
 

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i red on the msd forums and ken though the afs in mazda pid was the commanded, according to my testes the only commanded af is the one that says commanded in the fueling table. All others are actual
 
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 :)


You've got it backwards.. At WOT the car goes into OPEN loop mode.. in this mode fueling is basically determined by preset fueling in the map.. it does not take into account the a/f ratios to determine fueling..
At cruise/part throttle the car is in CLOSED loop mode.. this is using sensor feedback from the wideband to help determine correct fueling..Our cars also idle in closed loop mode..

some people may wonder why his car isn't throwing codes for running so far off from the commanded afr.. since fueling issue occurs while he is in open loop mode.. the ECU basically ignores what the wideband is reading .. it doesn't care that it's that lean and will not correct for it.. It will just assume that the fueling of the car is following it's set fueling map..
 
Run 1 Pic
Run 2 Pic
Run 3 Pic



looks like my car is keeping up with the commanded AFR just fine.. Chris, when you installed your DP, did you have any issues removing your wideband sensor?

what are your mods and whats your boost pressure as well as your temps.

my mods are
i/tbe/3.5 ets/forge bpv/map clamp and stock boost control. Boost hits and holds 18-19psi. Temps are in the high teen low 20s. Elevation is about 800 feet
 
what are your mods and whats your boost pressure as well as your temps.

my mods are
i/tbe/3.5 ets/forge bpv/map clamp and stock boost control. Boost hits and holds 18-19psi. Temps are in the high teen low 20s. Elevation is about 800 feet

i/cbe/pg testpipe/ets 3.5/forge bpv and stock boost. Temps where in the low 60's and elevation is seal level. I was hitting 16 psi.
 
the second o2 sensor is a compliance isue it hax no efect on the ecu it just verifies that the cats are there and working if not it causs the idiot light to come on. was car all warmed up when you did these test as in had run for 15 min of driving beacuse it takes a little time tll cats are all warm. personale i think that the map clamp/ets is where the problem is beacus noone dose more testing for af and emisions and every other concivable parameter that a stock car will see is the OEM manufacture.
 
this car is pissing me the **** off. im a **** hair away from trading it for an 04 s2000(argh)

Before you do, sell me your PG pump (chair)(moon)

hahaa jk jk.. S2ks are alot of fun though... and actually HAVE and aftermarket
 
s2000's are weak oversteering bastards. Ill kick your ass chris. if you get anything it better be an 05 evo, if used, and if you buy new get a X! My next car will be a Evo x, or I just say **** it an buy the 04 cobra Ive always wanted. LOL
 
the second o2 sensor is a compliance isue it hax no efect on the ecu it just verifies that the cats are there and working if not it causs the idiot light to come on. was car all warmed up when you did these test as in had run for 15 min of driving beacuse it takes a little time tll cats are all warm. personale i think that the map clamp/ets is where the problem is beacus noone dose more testing for af and emisions and every other concivable parameter that a stock car will see is the OEM manufacture.


The mapclamp and the ets have nothing to do with it. Have you ever thought you might have an exhaust leak where the sensor is. Possibly the sensor is just gone bad? My car has had the same mods with zero issues and so has his.
 
Did you replace the 2nd O2 sensor to its design position (worth a try) and removed the map clamp...?

You need to take a step back, take a deep breathe, and configure the car back to stock regarding the ECU. Then run your tests.

I have all the mods you have except for the fuel pump and I don't have any issues.

(huh)
 
s2000's are weak oversteering bastards. Ill kick your ass chris. if you get anything it better be an 05 evo, if used, and if you buy new get a X! My next car will be a Evo x, or I just say **** it an buy the 04 cobra Ive always wanted. LOL

Screw 'em all. Build a kit and have a lighter, no compromise car with a hand picked engine, drive train and brakes.
 
Before you do, sell me your PG pump (chair)(moon)

hahaa jk jk.. S2ks are alot of fun though... and actually HAVE and aftermarket

I had an S2K before the MS3. Yes there is an aftermarket, BUT, you better have some deep pockets to play in it. Bolt-ons hardly get you any WHP at all. CAI you might get 2-5whp, /E will net you a couple more but some E's actually cause you to lose power.

The only real way to get serious power on the S2K is to go FI. A SC or Turbo will cost you 5k for the kit. Then you need it installed and Tuned. To hit 12's you're looking at an investment of about 10k after all is said and done. Add that to the price of the car and you might as well just go buy a STi and call it a day.

However, the S2K is a beast when done right. There is also a motor swap kit for the Supra TT motor. However, the weak link to the S2K is and always will be the rear end. If you did Turbo your car you would never do a launch unless replacing the rear-end is something you can afford to do. The guys that put down serious power on the S2K do not lauch ever. Sideways has one of the fastest S2K's out there and he (as last I knew) never has taken it to the track with fear of tearing out the rear-end.
 
Ok, here ya go, I hopefully I got the right pid this time.
 

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