View Full Version : O2 Sensor Help with HP Tuners!

04-09-2012, 09:40 PM
Alright guys well i have been having a problem with my bank 2 sensor 1 O2 sensor. At WOT bank 1 reads 851, and bank 2 reads 56.... im pretty sure this is causing my car to knock on hard pulls... We have been reading all of this on HPTuners also... Any ideas?!

04-10-2012, 04:35 AM
At wot you cannot use your narrowband sensors as an accurate reference really. But it does sound like you are way off on one side or the other. The problem is, its hard to tell which one is off unless you use a wideband to check each bank.

Old Geezer
04-10-2012, 07:35 AM
Swap the sensors side to side and look???

04-10-2012, 09:57 AM
Are your O2s OK at idle? Or is one going high and the other low?

04-10-2012, 10:28 AM
At times idle bank 1 will read perfect and bank 2 will run lean if I let my car sit it fixes its self

04-10-2012, 02:08 PM
Well, it could be that bank 2 is lean due to your tuning to compensate, or it could be that bank 1 is rich due to your tuning as well. Whenever I have this problem, I usually check spark plugs, then rockers, then wire, then coil packs then exhaust. A good sized exhaust leak can cause this to be off as well, but remember, when you go WOT, the O2 sensors have NO input. They are just a reference then. You are running off of MAF, VE, PE or a combo of those 3.

04-10-2012, 06:59 PM
Here is a screen shot I have from our testing.... I'm also getting some knock(only when bank 2 freaks)

04-10-2012, 07:19 PM
Doesnt appear to be ONLY when it wigs out. That happens over the entire run. Unplug the sensor and see what it does.....They are not used at WOT anyway.

04-10-2012, 07:55 PM
Sensor unplugged car runs better when it wigs

04-10-2012, 09:05 PM
Very interesting indeed. Runs better at wot? Or in general?

04-10-2012, 09:13 PM
well when the sensor wigged it would cause my car to like misfire kinda like and running super rich when wot i dont really notice it much but 3/4 throttle i can feel it and ses light turns on.... when unplugged the car runs fine in general(defaults to 500 or something like that!)

04-10-2012, 10:35 PM
Ok, then I would replace both it and look at your tune again. Something like that can cause all sorts of issues that will affect both sides of the engine.

04-10-2012, 10:40 PM
I can see if they will replace them under warranty at my work but they are barely a year old and bank 2 was already replaced.... Lol

04-10-2012, 10:43 PM
well then there is possibly something else wrong. if the O2s were bad, then they can mess up plugs too. With a good set of plugs and O2s, there should be a very very very minimal different in the ltfts while driving. If they are opposite, there is a problem, and if they are way off, there is a problem too.

04-10-2012, 10:50 PM
So should I try and get the o2's swapped out then replace the plugs and see what happens?

04-10-2012, 11:18 PM
Would be good start at least.

04-24-2012, 09:50 PM
alright sorry for taking so long to get back but i got the O2 sensors replaced and swapped plugs and wires... so far i have not had a problem but i havent had it hooked up to hp tuners yet....

Thanks for the input guys...