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Discussion Starter #1 (Edited)
Hey guys just wanted to share what happened on my first datalog. Eventually when the car got up to temp it didn't want to idle normal I'd say it would stumble like it was gonna collapse but didn't. I noticed even starting the car it would idle pretty low around 600 and just getting into 550 rpm, it was normal idle for me but that is low I'd think (It's all stock except K&N and MSD Opti+coil). Now with the amazing EEHack program it told me it was ERR44 Left 02 Sensor Lean so I think I'll do the cylinder test on EEHack tomorrow. But my knock count was ridiculously high north of 6000 sometimes. There was no Knock Retard at all, and my Adv. Went up to 41 at one point on the highway so I would like to hear from anyone with thoughts thank you.

Cade
 

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The pics aren't loading for me either; and strangely I went to another thread and those pics loaded just fine; but not these.

First, CONGRATS on using eehack! The learning curve is steep but you're about to become a master LT1 mechanic.

One by one:
Knock count is just a counter that always starts at some random number; ignore whatever number it's at, the important thing is that it's not increasing. When it increases, that's when knock is happening.

Idle stumble: do you have stock injectors? How many miles on the car? Try turning on the AC and the headlights and see if the idle stumble goes away. If it does, one or more injectors can't handle the really short pulsewidths at idle with no load (take a look in eehack, they're probably 1.1 ms or so?) Your injectors either need to be cleaned or they're just junk. Stock LT1 injectors are not ethanol resistant and should be thrown in the garbage. You can certainly run fuel system cleaner through it. Walmart sells a big bottle of it cheaper than I've seen anywhere else, though I don't know how good it is relative to something like Chevron Techron.

Code 44: unless your exhaust manifolds have NO LEAKS and your AIR pump system is fully sealed off, O2 sensor lean/rich codes are just symptoms. The stumble at idle, if its an injector not opening due to really low pulsewidths, it's the injector, not the O2 sensor, that's causing that code. If you are still running stock exhaust manifolds (and that's not a bad thing), strongly consider removing them as soon as possible and having them planed flat at a machine shop. This will eliminate broken bolt problems for good.

Spark advance: what's the MAP reading when it was at 41 degrees? If the MAP is really low, that's why. Don't worry about it.
 

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CJ, I can see three pics but they are so small I can't read what your printout reads. Even with new eye glasses. It really wouldn't matter as I would not know what I was reading.:crying: Let's hope someone here can see & understand what you have going on.

Mark: Snowman-33
 

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CJ, I can see three pics but they are so small I can't read what your printout reads. Even with new eye glasses. It really wouldn't matter as I would not know what I was reading./vBulletin/images/ImpalaSSforum_2016/smilies/tango_face_crying.png Let's hope someone here can see & understand what you have going on.

Mark: Snowman-33
Haha they all say successful and I can see them but it won't let me see it in regular view where we can zoom in and scan and with the laptop screen waves it does not help I will keep trying to get the pictures up
 

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..... I will keep trying to get the pictures up

This type issue, combined with the unworkably low rez limits for direct copy on this forum, make this my automatic go-to;


IMGUR


Easy Simple Fast Free
 

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..... [snips]

First, CONGRATS on using eehack! The learning curve is steep but you're about to become a master LT1 mechanic.

..... Your injectors either need to be cleaned or they're just junk. Stock LT1 injectors are not ethanol resistant and should be thrown in the garbage. You can certainly run fuel system cleaner through it. Walmart sells a big bottle of it cheaper than I've seen anywhere else, though I don't know how good it is relative to something like Chevron Techron.



Code 44: ...... If you are still running stock exhaust manifolds (and that's not a bad thing), strongly consider removing them as soon as possible and having them planed flat at a machine shop. This will eliminate broken bolt problems for good.

......

Just to add that in a past life I considered injector cleaners as no more than snake oil. But, wife's SUV took to such instant cure with periodic CEL that I'm won over. Search showed Techron as most effective, and it boils down to the same ROI v. more quantity with 'The big cheap bottle' of SuperTech.



The out-of-plane manifolds caught my eye. First ever hearing this. I always figured the broke bolts are from factory over-tightening or bound-up spacers.
 

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Discussion Starter #8
I do have stock injectors which could be shot being so old and if they're not resistent to Ethanol which I didn't know, probably could be a suspect. About 138,000 miles, I got it at 120k. I'll try the A/C and headlight trick thank you. So Inj. Pulse width was left bank 7.28 and right bank 8.01 and O2 was left bank 648 mv and right was 120 mv at highway speed of 74 mph at 2253 RPM this is in the 1 of 3 pictures. Now for the MAP sensor say's at 38 degrees (the 41 degree's I didn't take a pic of but it's on the computer) 74.9 kpa. There are no exhaust leak's from the stock manifold's and my A.i.r pump is gone and manifold capped off. I actually had to cut off my two magnaflow muffler's which not sure when last owner's installed them but on both tubing of both muffler's they rusted through and can move them make them rattle (found my rattle and exhaust leak putter) but on some there was a clean plasma cutter circle around the tubing connecting the muffler which was weird to me so I'm waiting for new muffler's from spintech. I cut exhaust right where the two muffler's sit do you think that would set something wild? I've heard of not having O2 leaks anywhere near before or 12 inches after so just wondering. Thank you for your input and yes I'm absolutely willing to learn the curve and keep the LT1 it's done me good so I can't change it it's a great tame street car and for it's size it's very strong down low for stock everything.
 

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The out-of-plane manifolds caught my eye. First ever hearing this. I always figured the broke bolts are from factory over-tightening or bound-up spacers.
The outer cylinders warp outward. The machine shop said they were at least 0.020" out if not more. I will not reinstall another set of stock manifolds without having them planed. Cost of planing is cheap.

Cade - don't worry about your knock counts, but your BLMs are sky high. They should be around 128; higher numbers means the PCM is adding fuel. How's your fuel pressure?
 

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Good start. Now go to each image, click on the 'BBC Code' and Control-V into your reply. Voila!


 

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Post screenshots (or the actual datalog) of when the car is idling. You will be able to see if the car has an air leak by looking at the IAC's. BLM's and the voltage of the ICV. Your PCM is adding fuel into the trims on both sides, and its while @ cruise. This is usually an air leak. Put a vac gauge on the manifold and see what you see. A bad injector would affect one side and you're adding fuel to both sides pretty evenly.
 

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CJ, hi.
I find this confusing

EEHack program it told me it was ERR44 Left 02 Sensor Lean


your pic #1 in post 10 shows the O2 volts.
Left = .830
Right= .884

that's makes me think you have symptoms of rich condition not lean.

But as others have said, you need to figure out why there is too much or not enough fuel in the exhaust stream the O2 is measuring.

Just my .02.
-ALF out....
 

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CJ, hi.

your pic #1 in post 10 shows the O2 volts.
Left = .830
Right= .884
It could have been snapped on one of the swings of the 02's so we can't really tell anything from a screenshot. We need to see the actual logs. Ideally, a complete log that would include cold start, idle till closed-loop, drive around to operating temp, WOT, and then a hot idle.
 

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Discussion Starter #18
It say's "eedata" format is not allowed I tried to make a zip folder but it say's too large and it is 46 minutes long is there a way to trim it? BTW I ran the cylinder drop test and they all came out fine. 8cyl=22.5; 7cyl=22.3; 6cyl=22.4; 5cyl=22.1; 4cyl=22.2; 3cyl=22.0; 2cyl=21.0; 1cyl=20.6. I'm stoked to see all high number's this whole powertrain has been really reliable, I put stress on it sometime's but since it's stock it's not high stress. with 1 & 2 being lower I'm not worried cause I hear 8 and 7 make the most power because the air coming in can't flow or bend around for 1 and 2 cylinders. if it was any lower I'd ask about that.
 
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