Oxygen Sensor help........

[Rocket Man]

The O2 sensor seems to be always the "default" code for all issues so I replace the O2 sensor then the other one goes out. Apparently the 5.7 Litre has 4 O2 sensor's so what-replace them all or ignor?

First of all there’s no “default code” for all issues so I’m not sure what makes you say that. There’s 4 O2 sensors on most vehicles- 1 upstream of each catalytic converter, 1 downstream of each cat. The upstream ones are used by the PCM to measure AFR ratios so fuel mixture can be determined. The downstream ones are used by the PCM to measure how well the cats are working/ emissions data. They are designed to last about 100k miles give or take. Do you know how many miles are on them? The codes will tell you which sensor is throwing a code and why. But if they have 100k miles on them or more, you’ll probably end up replacing all 4 sooner or later and in fact your gas mileage might go up if they aren’t performing up to par. So are you getting a DTC and if so, exactly what is that code?

 

[dojrs]

Wow lots of information and differing opinions on this topic. I haven't had time to get back under the hoe and try putting an extender in there. someone referred to an EGT (exhaust gas temperature) sensor. it isn't that sensor. it is the upstream O2 sensors. I know sometimes knock off parts will work and other times they don't. At this current time it has some amazon specials in there (ECCPP) not sure where they're manufactured. coming from an engineering background so long as they quality of the parts is up to standard it should not matter what company name is on a part. however I may try getting some different brand O2 sensors and attempting that.
all that being said I do appreciate everyone's help in this matter. I'd love to see an increase in fuel economy, but with all the changes I've done, vehicle weight, and lead footed driving i have do get to drive it i know it has a slim chance in hades of getting better than 12-15 mpg lol.

 

[exp500]

This one or similar Denso makes AC mostly. About $20.
More Information for DENSO 2344012

 

[fasteddy]

BTW....I didn't see the codes it was throwing in the first post....was it just one? or both sides?
Sometimes a vacuum leak/issue can trigger both codes.
Big cams can cause vacuum issues.

 

[dojrs]

BTW....I didn't see the codes it was throwing in the first post....was it just one? or both sides?
Sometimes a vacuum leak/issue can trigger both codes.
Big cams can cause vacuum issues.

this is what im leaning towards also. yeah its throwing the code on both left and right sides. I dont know of any vacuum leaks at this time. however i do know when changing the cam it could have altered the amount of vacuum produced and therefore altering other things.
i think it maybe something i have to clear with my handheld scanner occasionally.

 

[swathdiver]

I know I'm not the sharpest pencil in the box but after reading three pages I didn't see what code(s) exactly are being thrown. Typically, when a heater code is thrown, either the O2 sensor is bad, the wiring or the ECM. That's it.

 

[Rocket Man]

I know I'm not the sharpest pencil in the box but after reading three pages I didn't see what code(s) exactly are being thrown.

Nope, 3 pages and the op still hasn’t shared the codes. It’s like the nuclear missile launch codes, all guarded and secret like.

 

[swathdiver]

Nope, 3 pages and the op still hasn’t shared the codes. It’s like the nuclear missile launch codes, all guarded and secret like.

Well, for all we know it could be a P0430!

 

[dojrs]

Well, for all we know it could be a P0430!

no secret launch codes here that im aware of LMAO I just dont remember the code number, just what the scanner said. Due to my frustration with totally dispising a check enigine light i cleared the code a week or two ago. i feel certain it will re-appear and when it does i will get the secret code for you all.

Four days ago I swapped the cylinder heads from stock 706 heads w/ chevrolet performance valve springs, and upgraded rocker arm trunions. the new heads are factory 706 castings that are CNC ported and polished, 2.00" intake valves, 650# valve springs, and the factory rocker arms with upgraded BTR trunions.

 

[Tonyrodz]

no secret launch codes here that im aware of LMAO I just dont remember the code number, just what the scanner said. Due to my frustration with totally dispising a check enigine light i cleared the code a week or two ago. i feel certain it will re-appear and when it does i will get the secret code for you all.

Four days ago I swapped the cylinder heads from stock 706 heads w/ chevrolet performance valve springs, and upgraded rocker arm trunions. the new heads are factory 706 castings that are CNC ported and polished, 2.00" intake valves, 650# valve springs, and the factory rocker arms with upgraded BTR trunions.

Are they Castech heads?

 

[dojrs]

Are they Castech heads?

original GM heads. was castech one of GM's suppliers for their cylinder heads ?
i ordered these from allied motor parts in Austell GA. they have great turn around time and were extremely helpful and knowledgeable.

https://www.alliedmotorparts.com/?m...MI9LmT143b7wIVmuCzCh31XA8OEAAYASAAEgJxq_D_BwE

 

[Tonyrodz]

original GM heads. was castech one of GM's suppliers for their cylinder heads ?
i ordered these from allied motor parts in Austell GA. they have great turn around time and were extremely helpful and knowledgeable.

https://www.alliedmotorparts.com/?matchtype=e&network=g&device=c&keyword=allied motor parts&campaign=933839433&adgroup=48181143538&gclid=EAIaIQobChMI9LmT143b7wIVmuCzCh31XA8OEAAYASAAEgJxq_D_BwE

Yes, but Castech heads are highly prone to cracks. It's a known defect with them. Iirc they crack around the headbolts.

 

[dojrs]

Yes, but Castech heads are highly prone to cracks. It's a known defect with them. Iirc they crack around the headbolts.

do you remember the casting numbers that castech supplied? the ones that came off were 706 castings. the ones that I put on were 862 castings. all the research I read said the largest difference between those two castings was the casting material(s) used. one had minimally smoother interior surfaces, If I'm remembering correctly the 706 castings were the ones more prone to cracking. I had a set i traded for that wound up having a hair line crack between the 2nd & 3rd cylinders so i was not able to do the porting and polishing myself on those heads. that's when a friend advised me of Allied. I very well may have been able to keep looking locally and eventually found another set that were usable, but everywhere i called either did not have any or wanted more than a cleaned remanned set from Allied. So I just said the hell with it and went balls to the wall and got the CNC heads from them.

 

[Tonyrodz]

do you remember the casting numbers that castech supplied? the ones that came off were 706 castings. the ones that I put on were 862 castings. all the research I read said the largest difference between those two castings was the casting material(s) used. one had minimally smoother interior surfaces, If I'm remembering correctly the 706 castings were the ones more prone to cracking. I had a set i traded for that wound up having a hair line crack between the 2nd & 3rd cylinders so i was not able to do the porting and polishing myself on those heads. that's when a friend advised me of Allied. I very well may have been able to keep looking locally and eventually found another set that were usable, but everywhere i called either did not have any or wanted more than a cleaned remanned set from Allied. So I just said the hell with it and went balls to the wall and got the CNC heads from them.

Yes. Castech heads were the 706 and if I remember correctly also 862's. Not all 706 heads were Castech heads. The non Castech heads are fine.

 

[Rocket Man]

do you remember the casting numbers that castech supplied? the ones that came off were 706 castings. the ones that I put on were 862 castings. all the research I read said the largest difference between those two castings was the casting material(s) used. one had minimally smoother interior surfaces, If I'm remembering correctly the 706 castings were the ones more prone to cracking. I had a set i traded for that wound up having a hair line crack between the 2nd & 3rd cylinders so i was not able to do the porting and polishing myself on those heads. that's when a friend advised me of Allied. I very well may have been able to keep looking locally and eventually found another set that were usable, but everywhere i called either did not have any or wanted more than a cleaned remanned set from Allied. So I just said the hell with it and went balls to the wall and got the CNC heads from them.

Here’s the TSB.
http://ww2.justanswer.com/uploads/Bluegorilla/2008-12-05_142924_Coolant_loss_5.3.pdf

 

[dojrs]

Well the codes appeared again. They are....... 0053. I also have just experienced a weird limp mode type of thing going on. The T/C came on by itself. Dry asphalt road 80 ish degree evening. Random as hell, trans doesn’t act right like it’s fuel starved maybe ?.?.?... plugged in my cheap little code reader nothing. No nothing at all. Cleared the O2 code and the 0455 Bc I’ve got an evap leak somewhere also. Won’t take fuel so I’m thinking its between the charcoal canister and the fuel input possibly. Anyone else ever had this T/C happen to them? Any ideas ??