I hate cars.

GTO has yet another issue, which we have narrowed down to the passenger side O2 Sensor...or so I hope.

Driving home from Philly the other day and all of a sudden it was a torrential downpour, standing water everywhere. Quite a few wrecks..so of course we're all of a sudden at a stand still or moving 10mph.

Car starts running horrible, misfiring, barely idling. Went from 30mpg to 2.6mpg, wasn't too happy with it so I limped it home from exit 27 in PA to the first exit in DE to RPM, we figured out the car worked fine after 50mph(no idea why) or 4k (when the MAF kicked in) so we turned them off in the tune and it ran fine, just dog piss slow until 4k lol

Waited until it was dry out to turn them back on, thinking it might've just been water in the harness.....NOPE. Runs like complete shit still.

I crawled under there today to check the wiring and its perfectly fine and just the way I had it when we did the header install.

On top of that, the tags are expired still (Temp tag expired tuesday) I haven't gotten a paycheck for the entire month of August so it's not like I can just buy the O2 sensor and then bam run it thru inspection.

I parked it until I get money again, and not even at my house..otherwise I'd be tempted to drive it.

Atleast it has company...



Melissa/Al....trying to get off that pass side O2?

If I had one I would give it to you Geoff. Sorry but it will work out.

Quote: Originally Posted by MVDCGTO... If I had one I would give it to you Geoff. Sorry but it will work out.

Thanks for the thought, Zach.

I threw a starter in the Jeep so I could atleast get to and from work, just sucks because I have no idea how long this engine will last, and I havent been able to start the rebuild of the 5.9 I picked up....it's still in the back of the truck.

Wait - so its the MAF or the O2 sensors?

Just unplugging one of the front ones will put the car into open loop - however it still uses the MAF and MAP sensor.

Unplugging the MAF will still keep the car in closed loop - it will use the MAP sensor and still correct with the O2 sensors.

Your MAF and MAP are used the entire time together under that 4k or whatever it is set at. If you are having problems under 4k only I'd look into your MAF. And how is it running like complete shit? Like is it missing? Knocking? Dumping fuel out the back?

Things I would try is disconnecting your MAF - if that keeps it running like shit disconnect an oxygen sensor (you don't need to take it out though) and reset the battery. And if it keeps that up by all means start checking shit like plug wires - cracked spark plugs, etc.

Also - if the O2 sensor failed it would throw a code and force the car into open loop (as long as the sensor 1 codes (the front o2 sensors) weren't turned off in tuning.

The passenger side front O2 sensor is the issue. and there is a code being thrown, CEL flashes at me occasionally.

Quote: Originally Posted by 3rdgenfan... The passenger side front O2 sensor is the issue. and there is a code being thrown, CEL flashes at me occasionally.

Ok, well for drivability sake you can just unplug the o2 sensor and that will solve the issue (with resetting the batter so you clear the shitty fuel trims). It won't correct the CEL obviously but its a good fix to get the car driving again if thats what it is.

However - I'm concerned that isn't the limit of it because when the O2 fails and throws a code it goes into Open Loop and consequently your car should run "fine" minus the light (like above).

Based on what you are describing I'm actually wondering if the MAP sensor is bad....

Quote: Originally Posted by andrewzpsu... Ok, well for drivability sake you can just unplug the o2 sensor and that will solve the issue (with resetting the batter so you clear the shitty fuel trims). It won't correct the CEL obviously but its a good fix to get the car driving again if thats what it is. However - I'm concerned that isn't the limit of it because when the O2 fails and throws a code it goes into Open Loop and consequently your car should run "fine" minus the light (like above). Based on what you are describing I'm actually wondering if the MAP sensor is bad....

It has the same exact symptoms of when the drivers side O2 went bad, we made it to where the O2s wouldnt effect the tune and the car ran perfectly fine, no misfiring, no CEL...nothing.

We turned them back on because we had originally thought it was an issue with water getting in the harness from the drive home with standing water and all. Originally BOTH sensors werent working intermittently, now it is just the passenger side acting up.

I don't have the money for a new sensor, and my tags are expired so I don't want to even bother driving it around..the way my luck has been recently, I'll end up getting the damn thing towed.

I'm sorry to hear this, good luck on the repairs. I know how you feel though.

It seems like my gto is in the shop every other week too. This time the back seat floor flooded again after a heavy downpour...and it shorted out the airbag connecter under the passenger seat. Of course the dealership claims they found the leak now, after my warranty expired. Oh well, we shall see.

geoff that sucks. if i had a spare O2 you know you would get it.

This is a deja vous thread. Didn't this exact same thing happen to you before when you drove through standing water? And then you posted about it running like shit and the bad fuel mileage you were getting?

Quote: Originally Posted by Jrzy Goat... This is a deja vous thread. Didn't this exact same thing happen to you before when you drove through standing water? And then you posted about it running like shit and the bad fuel mileage you were getting?

That time I hydroplaned and almost lost it, but yeah haha...this time it killed the other sensor.

Oh, and happened right before the Cecil shootout, too.

I think the appropriate title for this thread should be: "Cars hate me....because of what I do to them."

If you still need it @ the Cecil race i will pull the other one out for you

Al, I am hoping to have something soon, but I am not sure just yet. I'll let you know though, and appreciate the gesture more than you can imagine.

Ordered a few parts for the Jeep since my dad is covering the repairs on that, and returned the old starter for a core exhange...basically paid 3 bucks for a brand new OEM front O2 sensor.

Next on the list is either taking the tint off or having it 'passed'

Quote: Originally Posted by MVDCGTO... ... Sorry but it will work out...

And it did.

I returned my old starter because I forgot we had the core exchange on it. Got to NAPA, and the lady there applied that core return to my next purchase(since I am still getting stuff for the Jeep) I ended up paying 4 bucks for a brand new O2, installed it today and took off my tint. Passed inspection and tagged the car.

I am 100% legal now, and because of this...I bought myself a new vanity plate. Actual plate won't be in for a few weeks, but they put it on the stickers.

Behold:



404222 is the "old" plate number so don't worry about that.

That is gonna be the gheyest vanity plate to ever be put on a GTO.

GREAT news buddy!

Quote: Originally Posted by 3rdgenfan... And it did. I returned my old starter because I forgot we had the core exchange on it. Got to NAPA, and the lady there applied that core return to my next purchase(since I am still getting stuff for the Jeep) I ended up paying 4 bucks for a brand new O2, installed it today and took off my tint. Passed inspection and tagged the car. I am 100% legal now, and because of this...I bought myself a new vanity plate. Actual plate won't be in for a few weeks, but they put it on the stickers. Behold: 404222 is the "old" plate number so don't worry about that.

.cx