Tchleung

So after I got my car running, I mainly drove around town, nothing major. No real high speed cruising or anything. After about a day driving, the first base map tune I whipped up VIA ZDYNE was pretty rich. cruising around town was around 12-13:1. WOT was around 10:1. then my CEL came on and it was throwing an O2 Sensor code. BTW, my car is OBD0 B16 so it has 2 O2 sensors. Anyways, I reused o2 sensors from my previous setup which worked fine. I did rewire the sensors but the connections are perfect as I double checked. I'm wondering maybe running overly rich the first day fouled one or both maybe? Anyways back on topic. So I am still throwing the code obviously, I noticed that whenever I take my car onto the highway for a period of time and am cruising in vacuum around 15-20in vacuum the car will all of a sudden hesitate and buck quite badly cruising. I look at my a/f gauge and it's deep in the 18:1-19:1's!!! I was like wtf. whenever I give it more then say 30% throttle it goes away but as soon as I cruise in that vacuum again for a bit it'll go super lean again. I thought maybe it was a fuel multiplier problem in 5th, so I get back into town and it does it in any gear at that load. Whenever I shut the car off, and turn it back on. the problem goes away. but as soon as I hit highway again. It's there again. damn lean condition... I can't just add fuel at those values because when it's not having the problem, it's running perfect a/f.s so if I add fuel it'll run pig rich. I also noticed last night I did quite a bit highway test runs setting up my boost controller and not once did it happen. It's as if the car isn't being pushed. then **** goes bad... I even tried and disabled open loop on the ecu and it still has the problem.. Could it just be that my O2 is really faulty? I'll be replacing both of them tomorrow. damn this was a long dragging post....

0mtber

iTrader: (2)

What wideband are you using ?

Tchleung

PLX M500

Alchemist

Im not sure what it is but here are some things to think about:

1.)When you decel while in gear, the AF values should go extremely lean. Maybe when youre on the highway your foot is actually easing off the gas and youre getting those decel values.

2.) Maybe you have an exhause leak at the wastegate or charge pipes and excess air is flowing in, throwing off your readings.

Tchleung

That's what I had thought at first, but when it does it after the highway in town at 15in vacuum. I'm no where near decelleration. No exhaust leak

Turbo E

10:1??? thats awefully rich. you may have fouled out your o2 sensors. take a peek at em.

also are you using OEM o2's or some NTK/bosch universal garbage?

Muckman

iTrader: (2)

Agreed 10:1 is awfully rich. And even 12 is too rich for light cruise. You can tune light cruise to 14.7 to save on gas and be safe.

dustin

Where do you have the O2 sensors? The OBD0 B16 ecus freak out if you remove the O2 sensors from stock location (on the correct runners).

Tchleung

I ahve them both on the downpipe under the oil pan. Same as my old setup which worked fine.. I'm hopnig I jsut fouled my seneors so I'll replace them asap.

Tchleung

Installed 2 new o2 sensors today. gonan test it out tomorrow morning..

Tchleung

So my CEl seems tob e gone.. but it still sputters etc on the highway. I notice it doesn't happen allt he time. maybe 50-75% of the times. It's as if I stay at a costnant load on the highway too long it'll do it. It also did it a few times crusing in 5th around town. I idled and it was idling at like 16:1 then out of teh blue it'll go back up to 14:1 and all of a sudden run fine... Any ideas? hwhen driving, it's almost as if the off throttle/deceleration fuel cut is comnig on too early MAYBE.. but I can't change that on zdyne.

jeremydde

My CRX with OBD0 B16a did these before too. CEL was on as well (o2's were burned out). I changed the o2's then after driving on the highway for awhile then going part throttle for a bit the air fuel would "hunt" unless i was over more than 20% throttle or so, then the car would richen up immediately. I traced the problem to wiring the o2 sensors backwards. There will be no CEL if they are backwards by the way. If they are backwards the ECU will constantly try to correct the wrong cylinders for fuel ratio and make 2 over rich and the other 2 lean and back and forth. If you moved the 02 sensors downwards then that could be your problem because one sensor monitor cylinders 1 and 3 I believe and the other monitors 2 and 4. Moving them down so that the exhaust gases are effecting them differently than factory will give you nothing but problems.

Unsivil_audio

Disable closed loop if not already done. Also try resetting your ecu.

J337_UNIT

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Turbo E &raquo;</TD></TR><TR><TD CLASS="quote">10:1??? thats awefully rich. you may have fouled out your o2 sensors. take a peek at em.

also are you using OEM o2's or some NTK/bosch universal garbage?</TD></TR></TABLE>

10:1 A/F ratio wouldnt cause an O2 to get fouled out.

Tchleung

I repalced the O2's alreayd and fixed the CEL. but still getting the majorly lean condition. I disabled closed loop to only run open loop and problem persists. I alsor eset ECU. I read in a thread maybe my map sensor took a **** and is giving false values when udner light load. so I'm gonna rehook back up my GM2 bar and see if it goes away. I don't recal having the problem with the GM2 bar, although I only ran it for a shrot period of time.. let you guys know this evening.

Tchleung

so put the 2 bar in today and retuned the car. it seemed to still abve the problem at first. then I drove on highway a few tiems and it hasn't come back yet.. I'll be on the highway for about 200miels tomrorow so we shall see...

Tchleung

welp. the O2 code is still being thrown. and it still stumbles very lean soemtimes. sometimes it doesn't do it. sometiems it does... I know the ECU always rememebrs the code until reset. but the CEL on the dash doesn't awlays go on right awya. noticed on my drive home, when the CEL went on for 02. I didn't ahve a problem with the lean condition where as before the lamp went on.. althought his could just be a big coincidence.. I'm gonan unplug the 02's next so it forces the CEL to go on and also keeps ecu in open loop to read off my maps and see if that fixes the problem.

Tchleung

I changed my fuel filter, also unplugged the 02 sensors and disabled closed loop and the problem has seemed to go away..

DurboDug93

That sounds a lot like the problem i have been having.

https://honda-tech.com/zerothread?id=1242732

johnzm

its his 02 sensors. sorry u gota mess with your wiring. you DID NOT disable them if its tripping a light for them.

unplug the o2's turn them off on th ecu, and throw them out. or u can converty to obd1


my car would do the same except the other way around BADLY it would drop below 10:1 cruising. ended up being 02 issue.

the dual 02 setup is nothing but troble, especially on a boosted car

dustin

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dustin &raquo;</TD></TR><TR><TD CLASS="quote">Where do you have the O2 sensors? The OBD0 B16 ecus freak out if you remove the O2 sensors from stock location (on the correct runners).</TD></TR></TABLE>

Tchleung

Hey, I'm a moron and forgot that my ZDYNE ecu is made from an LS ecu with vtec etc etc added, so it only uses 1 O2 sensor anyways like a stock OBD0 LS. I unplugged the O2's and disabled closed loop on the ECU but it still throws the damn O2 cel.. Maybe the ecu isn't disablnig it like it should. cause when I had the ecu disabled for o2 ensor and had them still plugged in, in bosot I ahd my tune perfectly. After unplugging the O2's. the car was a godo ponit leaner for some reason so I ahd to retun the car with no o2 sensors hooked up.. I dunno. this is weird... I got about 1000miles of driving over the weekend again so we'll see what's up.