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Old 08-26-2020, 03:10 PM   #1
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Thanks for the nice explanation Blue62!
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Old 08-26-2020, 03:47 PM   #2
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Agree! Thanks for posting the explanation.

Could not find vacuum leak and the SAI pump/fan turns on and off. So I was thinking it's something else.

But appreciate the response and will looks more closely at the SAI system as a whole. Lots of good info on here to research.
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Old 08-27-2020, 06:22 AM   #3
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Originally Posted by Zzorro View Post
Agree! Thanks for posting the explanation.

Could not find vacuum leak and the SAI pump/fan turns on and off. So I was thinking it's something else.

But appreciate the response and will looks more closely at the SAI system as a whole. Lots of good info on here to research.
I think with 175k miles on your car that the plastic hoses, connectors, one way valves and vacuum canister on the SAI system are in need of replacement.

I watched the video you posted the link to in your other post.
He shows the layout and parts involved pretty well.
The SAI system is fairly basic you would just be replacing a few parts.
I would think you could replace everything but the pump for around $200.00
$250.00 ??
I would think you could find vacuum hose and tee or y type connectors at an auto parts store or hardware store that would work.

If your not afraid to turn a wrench I thing you can fix the SAI issue with a little time and a bit of cash.

Let us know how you go.
I am always interested in out comes of those I try to help
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Old 08-27-2020, 06:57 AM   #4
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Thanks again. Yup, the SAI seems an easy enough job. I'll add it to the list!

Might take a while to get to it. But I will post up results and findings. I too like seeing how issues got resolved on here. Helps folks in the future.

I've got a couple of O2 sensors ordered already. So I'll swap the one that throwing the code seeing as it needs doing.
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Old 08-27-2020, 07:44 AM   #5
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Zzorro

You said the Air pump works so I am going to assume you triggered it with your Durametic to check it.

So you need to make sure the air pump kicks on when you first start the car from a cold start. Confirm that it kicks on from cold start before going further.

This is why.
One of the things the DME/ECU looks at on cold start is coolant temp.
If the coolant sensor shows close to ambient temp. (cold engine). it triggers the SAI air pump.
If by chance your coolant temp sensor does not show close to ambient temp. at cold start.
Then the DME/ECU is going to react as if the engine is already warm so it will not trigger the Air pump. Thus possibly triggering a SAI code.

So a faulty coolant temp sensor that still operates but not properly can trigger other codes without triggering a fault code for a faulty coolant sensor.

Damn
I hope that makes sense
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Old 08-27-2020, 08:48 AM   #6
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Originally Posted by Zzorro View Post
Thanks again. Yup, the SAI seems an easy enough job. I'll add it to the list!

Might take a while to get to it. But I will post up results and findings. I too like seeing how issues got resolved on here. Helps folks in the future.

I've got a couple of O2 sensors ordered already. So I'll swap the one that throwing the code seeing as it needs doing.
You may as well change out all the O2sensors you have replacements for at once.
As after rereading your first post I see you have codes for adaption range issues on both banks.
Those codes could be caused by the SAI issue.
Or the O2 sensors could be causing the SAI issue.
But with 175k miles if the O2sensors are original then replacing them first may be more prudent.
Easiest things first.

Last edited by blue62; 08-27-2020 at 09:21 AM.
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Old 08-27-2020, 05:13 PM   #7
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Thanks Blue62

One clarification, I have 175k kms or 108k miles. But same difference. The car is up there in age and miles and stuff needs replacement.

To answer your specific questions:
1: yes, will swap O2 sensors. Explanation of my rationale below.
2: yes, I can turn on SAI pump with durametric.
3: yes, SAI turns on on cold start, have confirmed it.

I am suspecting O2 sensors over the SAI because:
-all the other codes thrown
-smells to me like it's running rich on idle. Totally subjective opinion
-engine bogging issue (and subsequent CEL) happens after the car is warmed up and in higher revs.
-you pointed out that one of my O2 sensor heater elements is probably pooched anyways.

For the benefit of those joining in the conversation:

Based on my research on here and other places, the primary culprits are 1) MAF, 2) vacuum system (which the SAI plays a part in) and 3) O2 sensors.

1) I already replaced the MAF (and that made a huge difference). 2) The SAI functions and I could not locate a vacuum leak easily (idle drops when oil cap is pulled off and starter fluid sprayed near the hoses and parts did not blip idle at all). 3) Next on the list is the O2 sensors.

Should note also that I replaced my AOS already and that did get rid of blueish smoke on startup.
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Old 08-27-2020, 05:44 PM   #8
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Quote:
Originally Posted by Zzorro View Post
Thanks Blue62

One clarification, I have 175k kms or 108k miles. But same difference. The car is up there in age and miles and stuff needs replacement.

To answer your specific questions:
1: yes, will swap O2 sensors. Explanation of my rationale below.
2: yes, I can turn on SAI pump with durametric.
3: yes, SAI turns on on cold start, have confirmed it.

I am suspecting O2 sensors over the SAI because:
-all the other codes thrown
-smells to me like it's running rich on idle. Totally subjective opinion
-engine bogging issue (and subsequent CEL) happens after the car is warmed up and in higher revs.
-you pointed out that one of my O2 sensor heater elements is probably pooched anyways.

For the benefit of those joining in the conversation:

Based on my research on here and other places, the primary culprits are 1) MAF, 2) vacuum system (which the SAI plays a part in) and 3) O2 sensors.

1) I already replaced the MAF (and that made a huge difference). 2) The SAI functions and I could not locate a vacuum leak easily (idle drops when oil cap is pulled off and starter fluid sprayed near the hoses and parts did not blip idle at all). 3) Next on the list is the O2 sensors.

Should note also that I replaced my AOS already and that did get rid of blueish smoke on startup.
Your p1128 and p1130 codes for oxygen sensing range 2 are interesting in that one code is saying your at the lean limit on one bank and at the rich limit on the opposite bank. So replacing the O2 sensors may very well take care of those two codes.

Also if you have faulty O2 sensors the SAI can fail it's self test because the ECU uses O2 sensor reading to confirm air injection (lean condition) in the exhaust when it triggers the air pump for the self test.

Watching with interest
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Old 08-26-2020, 03:49 PM   #9
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Thanks for the nice explanation Blue62!
Thank you NewArt.
Just trying to help the community where I can.

The more you understand a system, circuit, sensor.
And how they relate to other systems, circuits, and sensors, the easier issues with them are to resolve.
That's what I tell myself anyway.

I do wonder many times when I try to explain something via this venue.
Does it make sense to another person that reads it? Has it helped?
Could I have explained it another (better) way ?
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