[electrickrypt]

I have an O2 sensor that has gone bad so I went to get a diagnostic and it read Bank 1 Sensor 1. I know there are three O2 sensors but I am not sure which one is Bank 1 Sensor 1. I Googled and searched the forums and found nothing. Also checked the manual and nothing. Anyone know exactly which sensor Bank 1 Sensor 1 is? I am hoping it is one of the two that are in the front by the engine/firewall and not the one on the exhaust under the shield that is held in place by rivets.

Thanks
electrickrypt

 

[JimD]

That sensor is in the exhaust manifold (very close to the head) for the RH bank which is the firewall side of your engine.

 

[electrickrypt]

So that sounds like the one I was hoping that it wasn't... underneith the car.. Under the rivitted plate. I'll have to look into it and match up your description with the manual's when I get to it.

 

[Ranger]

No, it's not under the car, but you'll wish it was. It is on the exhaust manifold (between the engine and the firewall).

 

[electrickrypt]

Two of the sensors are 'upstream' and one is the 'downstream'.... So bank 1 sensor 1 is the one downstream sensor correct?

 

[JimD]

What part of Post #2 are you having trouble understanding or believing???

 

[ewill3rd]

Sensor one is closest to the engine, so no it is not downstream and it isn't the one behind the shield.
As Ranger said, you'll wish it was.
You probably can't even see it from under there very well, follow the pipe up to the engine and look around in the manifold of the rear bank. That's it!
Good luck.

 

[electrickrypt]

Its the one ahead of the catalytic converter, on the top of the rear exhaust manifold. That's what the guys at the auto shop told me anyways.

Im not a mechanic and know very little about cars so im just trying to make sure im changing the right one.

The manual explains near to nothing and the pictures are so close to the O2 sensor to where you can't see where you're looking at. Would make things a lot easier if the book labeled the sensors. Two upstreams and one downstream, that's all it basically says... and how to remove them.

 

[Submariner409]

Your engine has 3 O2 sensors: one in the collector section of each exhaust manifold and one just after the catalytic convertor (the one up above the riveted heat shield). So you have two sensors upstream of the cat and one downstream.

The O2 sensor in question is the one in the top of the exhaust manifold nearest the firewall. As posted earlier, you'll wish the bad one was the one behind the cat/heat shield.

If your manual explains nothing, then you need to find a GM/Helm Factory Service Manual at eBay or www.helminc.com. Haynes and Chilton's are far too generic for anything beyond oil changes.

You don't need anyone else to do your own diagnostic code reading: it's already built into the car. Read the sticky at the top of the page entitled "Got codes? Look here" or "How to pull codes". You're looking at the OBD-II code procedures.

 

[electrickrypt]

I found the O2 sensor. lol. Low, behind the engine, on top of the exhaust manifold. lol again. I totally see what you guys were trying to explain to me now.

I've been on it for three hours now, dropped the engine a little bit to gain more access to it. The problem is, trying to get passed the two solid radiator fluid tubes that wrap around the back of the engine.. blocking access for the 02 sensor ratchet extension from getting into position in order to remove the sensor itself. haha. Looks like I'll be busy for a while along with purchasing more radiator fluid.

It would have probably been a lot less stressful just driving the car the way it was... Wish me luck!

Thanks,
electrickrypt

 

[electrickrypt]

Finally, I got everything in place. Still get the same results as it was before replacing this O2 sensor. Perhaps try and replace the other 'upstream' sensor? :bomb: The one I replaced was the one you can see by looking straight down behind the engine, on TOP of the manifold, between the engine and firewall.
It sure was a long day.

My left muffler shakes and causes my car to rumble along with rattling something underneath... not sure if that would help.

 

[Ranger]

That is Bank 1 Sensor 1. No sense in replacing others if they are not throwing codes.

 

[ewill3rd]

Clear the codes and drive it.
If you didn't clear the code the light will still be on and the code will still show until the code runs and passes several times.

 

[electrickrypt]

Yea I cleared the codes. Then the light disappeared, but only because there were no codes. After driving around for about 10 mins, the light came back on along with the code. PCM P0300 current.

Before replacing the sensor, the diagnostics test at the shop read bank1 sensor1 - low response,... which I am pretty sure that is what the P0300 is.

Im not sure if it will help but I still need to replace my spark plugs and will be doing so when I get the chance. Maybe the bad spark plugs are a contribution to the low response on bank1 sensor1? Not sure, but they need to be replaced anyways.

 

[Mark C]

P0300 is a misfire code. won't tell you which cylinder, but you have a problem with a plug, wire, or coil.

 

[ewill3rd]

The O2 isn't going to cause the misfire.
You have another problem.
Look over the plugs really well.

 

[Smokey727]

Any tips on this replacement have same issue on 2001 eldo

 

[Submariner409]

Not bad for a 9 year old thread. Tips? Engine warm, up on a 4-point lift. Correct slotted O2 sensor socket, long fingers, patience. Do not unduly twist or bend the new O2 sensor wire harness. DO NOT touch or get anything on the sensor tip.

You may have to use a transmission jack and lower the rear side of the engine an inch or so.

All covered in Post 59 and others in your Eldorado thread on the same subject - "Stored 7 years ......".