kpro question/ oxygen sensor

[Bishops223]

So i had my car tuned a few weeks ago and my tuner left my car run in open loop, he said it was because i needed a new primary 02 sensor, and now im throwing a code for air/fuel ratio sensor....if i replace the primary 02 sensor do i need to change the settings in kpro to closed loop? or keep it running in open loop with the new sensor just wanna get this straight so i dont spend $220 on a 02 sensor that does nothin for me, i hope this is the problem my air/fuel ratios are jumping all over the place sometimes

[Bishops223]

or can i keep it running in open loop and just replace the stock o2 sensor with a wideband 02 sensor?

[WPB EP3]

You need a working primary sensor to run in closed loop and to display correct A/F ratios. A solid, complete tune will run well in open loop.

[AKEP]

you can set in kpro, where you want open loop to kick in, usually WOT column. so you can still put it in closed loop and partial throttle will tune itself, assuming other parameters are set correctly. I don't want to drag this out, but basically if its partial throttle it only needs to be close, but you want wot tuning perfect.

you need a normal oem primary to do anything. aftermarket widebands are for visual reference.

[Ba82Ep3]

:facepalm: You think this might have something to do with the issues in your other thread??

Check the plugs and wiring to be sure the sensor is connected. If it is, spend the coin for a new OE wideband sensor. $220 is a lot cheaper than a new engine...

[AKEP]

:facepalm: You think this might have something to do with the issues in your other thread??

Check the plugs and wiring to be sure the sensor is connected. If it is, spend the coin for a new OE wideband sensor. $220 is a lot cheaper than a new engine...

and yeah since you're boosted, things like this happen. if kpro isnt showing afr's then just get a new o2. you dont wanna be hitting boost without knowing how much fuel you're using. this is where a good tune is saving your ass. the tuner probably left your maps a little fat on fuel so you dont blow the motor if something like this happens.

[Ba82Ep3]

By the way, the OE primary o2 sensor IS wideband.

If you got tuned, THEN added the aftermarket fuel pump, you will see variations in your tune. In KPro you can change injector sizes (say 440 to 650), but even though you are informing the ECU... your tune will be off because there are variations with injector delivery.

In your case (depending on the health and cleanliness of your fuel system), adding your Walbro fuel pump could have really thrown the tune you paid for way off. Now youre running open loop on a tune that is probably choking on fuel.

Please pull your fuel rail, clean your injectors and rail, flush out your fuel feed line, check your FPR for proper operation, and be sure the fuel in your tank doesnt have crap floating around in it. If it does, then that slit in the fuel feed line you referred to before has allowed crap in your fuel system... which will make your tune worthless in open loop.

Once all of that is checked out... and is OK... THEN change your primary o2 sensor and check the box for closed loop in KManager. Drive the car and see if it is any better...