Toadman1

I've been a member here for years but can't get the password to work but anyways my car isn't running good as usual. Since I started driving it I have been having issues with getting on the gas and the car sputters off an on. It does it full throttle and also just regular crusin. Also the SES light flashes for around 5 seconds. Also the exuast makes a funny thumping sound which I never heard before So I hooked a ODB test too it and got code P.1133: Manufaturer Control Fuel Air Metering. I believe this is my O2s from searching but not sure. I have Kooks longtubes and catted Y pipe for about 4 or 5 years. I have had the SES light every year go off an on but it never made the car run like this. What could be the problem and a remedy for it? Would unhooking the battery maybe fix this?

NoGo

iTrader: (2)

I don't have my ODBII book around, but I think that is the insufficient O2 switching code for bank 1.

I'm guessing you have a bad forward O2 sensor on the drivers side. I'm also guessing that the car is running discusting lean on one bank, hence the hesitation, exhaust popping and misfires (indicated by the flashing SES).

Toadman1

Should I just replace the left one then?

nmass399

yeah its the the H02S insufficient switching bank 1 sensor 1. Have you done anything to the car recently before you started having this problem, check wiring, pull out the 02 and see if it is in good shape.

Toadman1

I haven't done no mods for a few years. It sits during the winter and the battery died so I got the car started and left it run for 20 min. I have longtubes and catted y,slp airbox and slp maf mods done to the car.

JonCR96Z

iTrader: (33)

It's probably a dying O2. The switch points need to be tuned to make O2s work properly and improper fueling can lead to O2 failure.

I'm sure replacing will make your car run better for now.

Toadman1

I switched the front driver side O2 sensor. The ses light is still on and it still misfires and sputters. I noticed when turning the car on the exhaust sounds normal (evden after heated up) but after like 30sec its starts to make the sound again that kinda reminds me of popcorn or something. Does the car need to tune itself again? I only drove it 10 miles since the swap today.

NoGo

iTrader: (2)

Sounds like the problem is coming into play when it switches to closed loop - which happens in less then a minute after first starting the car.

In closed loop the car begins to reference the O2 sensors for fueling.

Try unplugging the front two O2 sensors and see if he car runs without the misfires. This will hold it in open loop (not referenceing O2 sensors). If the running cleans up then the problem is isolated to one or both of the front O2 sensors or related wiring.

Toadman1

Thanks for the info. Do I have to use the O2 sensors?

Toadman1

The O2 I took out was all black. i dunno if that would help pinpoint the problem.

NoGo

iTrader: (2)

All black just means the car is running overly rich....or poor combustion. It just backs up what was suspected: the a/f of the car is not correct.

You need the O2 sensors to pass emissions.

Did you try unplugging the front two on both banks?

Toadman1

I was trying to tonoight but had trouble since I didn't have the car up. I'll try when I'm off or it is light outside in the early evening. What I did notice was the misfiring sound through the pipes and followed it up to the top of my engine on the ls1intake manifold(I believe that whats its called.) Standing in front of the car at the airbox their is a sound coming from the left side of the ls1 intake manifold that sounds like a missing. The right side kinda sounds sounds like a paper in a fan while the left side has the sound but isn't constant. Whats confusing is if my ses light is from the drivers side but then why does my left side in the engine sound like a miss. Also everytime I start the car after sitting for a while it idels great but as soon I drive it even around alot it starts to miss and even sitting in it you can feel the car vibrating from it.

I could hook those up for inspection but if it is in sensor area can I run the car with no problem? Also how can I adjust the few mixture to even it out?

NoGo

iTrader: (2)

I wouldn't get rid of the O2 sensors. I still think the problem has something to do with one of your two O2 sensors or associated wiring.

Unplugging both front O2's for a little test will confirm it.

Once you find the issue, the fuel mixture and such will come back into line.

Toadman1

If it doesn't rain I'll unhook them tommorow and post.

Toadman1

I unhooked both O2 sensors and the car doesn't have the misfire while sitting. I took it for a short ride and it seemed good. I want to take it for a further ride though to see if the problem is gone. Whats my next step if it runs fine with them unhooked?

sunsetorang01TA

I've had the same problem a few years ago. Your best bet is to get new o2's. I would recommend Denso's. I just bought a pair of them. Many guys from the board here like them. Either that or you can run open loop all the time. I did it for over a year an a half. I'm sick of it now though. Your car will def run alittle richer and lose gas milage. Good Luck.

NoGo

iTrader: (2)

If the new O2's don't fix the problem then you have to start looking into the O2 wiring. Chaffed O2 wires causing a short happens on LT cars.

Toadman1

Should I hook each side up by itself and see which is bad or won't it show the problem that way?

NoGo

iTrader: (2)

I've never done that, so I'm not certain if it will work. If you loose the O2 on one side, I don't know if kicks the whole car to open, or just that bank....good question.

I say try it and see if it works.

Toadman1

I had the car out and it started to misfire and sputter again without the front o2s hooked up. So I'm guessing thats not the problem now. Could it be either my fuel filter,spark plugs of MAF causing this or any other ideas? It most noticable when in overdrive and tapping the gas or if ASR comes on and car shifts into second and trying to accerate.