P0300 & P219A codes

[asilverblazer]

I'm a little inclined to suggest drive the hell out of it for a bit, let the PCM have some time to read sensors and adjust things. Lots of parts have been changed potentially 'surprising' the PCM with new readings that it hasn't fully adjusted to.

 

Drive it an hour in varying conditions, then check the miss fire counts and long term fuel trims. If after doing so, like above, you have what seems to be an obvious fault on cylinder 2. Put one of the other injectors on it and repeat.

 

Since the MIL isn't flashing the problem isn't TOO bad... I would be concerned about killing the catalytic convertors with a significant miss fire over fueling.

[ktuck]

5 hours ago, newdude said:

 

 

 

Are you buying these?  8pcs Genuine 12668390 GM Fuel Injectors For 14-19 Chevrolet GMC 1500 5.3L FJ1217 | eBay

 

I hope not...Those are NOT "Genuine GM", especially not for $140 for all 8 of them.  Those are counterfeits/aftermarkets made to look GM.  The packaging alone isn't even correct.

 

12710481 is the current OE number.  There are many legitimate places they can be purchased from at a discount, but are about $80-110 each from legit sources.

 

Here's the labeling on the OE injectors:

 

 

 

 

Compare that to the ones in that Ebay link:

 

 

 

The GM logo is incorrect, the font for the "A" and the font of the casting # on the body don't match.

 

 

 

 

Yes, I must that due to the cost savings, I unknowingly fell for the $140 set of 8 "GM" injectors. Below I posted a pic of one of my original injectors and then one of the ebay specials. On the original factory injector, it is clear the font height of the letter A is above that of the part number that follows, on the ebay injector the height of the A is even with the height of the part number. Also, the number on the second line below, is the same on all of the ebay injectors (0615606065). Whereas on the original factory injectors, that number on the second line is different on each of them. I don't know if that means anything or not.

 

You were the first person to enlighten me about fake aftermarket injectors and since I've had others tell me the same thing. At this point, I am considering sending all 8 of the original factory injectors off for testing, and then only replacing those that fail the test. As I recall, nothing improved when I installed the first set of "GM" injectors and it seems that the misfiring went from intermittent to constant all the time. Before that, I recall driving the truck for perhaps several days and maybe a few hundred miles between misfire flare ups. That hasn't been the case since, it is missing right from initial cold start up and does not go away even breifly.

 

 

[mikeyk101]

It isn't just the "A" that is off but several of the numbers as well. Different are the slash in the 0, as well as the font in the 2, 3, 6 and 9. It really sucks that so many fake parts are out there floating around.

 

I'd be curious how much a profit can be made selling fake substandard parts at substantially less than their copied twin. Obviously it must be decent or it wouldn't be happening. 

[ktuck]

12 hours ago, mikeyk101 said:

It isn't just the "A" that is off but several of the numbers as well. Different are the slash in the 0, as well as the font in the 2, 3, 6 and 9. It really sucks that so many fake parts are out there floating around.

 

I'd be curious how much a profit can be made selling fake substandard parts at substantially less than their copied twin. Obviously it must be decent or it wouldn't be happening. 

 

Yeah, I hadn't notice that, but you are right. Also, if you look at the numeral "1", the factory injector has simply a straight line going down to the bottom, while the fake one has horizontal base at the bottom of the number. I too wonder how they can make money off counterfeiting these because surely it takes a certain amount of time and expense to make a duplicate that looks this close to the original, then they sell a set of 8 for just a tad more than one normally costs.

 

Anyway, my great hope is that this ends up being the source of my misfire problems.

[ktuck]

20 hours ago, asilverblazer said:

I'm a little inclined to suggest drive the hell out of it for a bit, let the PCM have some time to read sensors and adjust things. Lots of parts have been changed potentially 'surprising' the PCM with new readings that it hasn't fully adjusted to.

 

Drive it an hour in varying conditions, then check the miss fire counts and long term fuel trims. If after doing so, like above, you have what seems to be an obvious fault on cylinder 2. Put one of the other injectors on it and repeat.

 

Since the MIL isn't flashing the problem isn't TOO bad... I would be concerned about killing the catalytic convertors with a significant miss fire over fueling.

 

I think that may be a good idea, after all I haven't run it very long for the computer to process all the new data its receiving and adjust to it. I have nothing to lose at this point, and if the codes and misfiring remains, I am prepared to send my original factory injectors off for testing. I have found a place in Ohio I plan to send them to. If I am correct, these are GDI injectors? Correct me if I'm wrong because they indicate on their website there is a different process involved in testing GDI injectors from port fuel injectors. I'm kinda thinking my original injectors weren't bad to begin with. I was just taking a shot in the dark at that point, and it seems the issue intensified following that. The problem went from intermittent to full time. 

[ktuck]

On 5/22/2024 at 11:37 AM, asilverblazer said:

I'm a little inclined to suggest drive the hell out of it for a bit, let the PCM have some time to read sensors and adjust things. Lots of parts have been changed potentially 'surprising' the PCM with new readings that it hasn't fully adjusted to.

 

Drive it an hour in varying conditions, then check the miss fire counts and long term fuel trims. If after doing so, like above, you have what seems to be an obvious fault on cylinder 2. Put one of the other injectors on it and repeat.

 

Since the MIL isn't flashing the problem isn't TOO bad... I would be concerned about killing the catalytic convertors with a significant miss fire over fueling.

 

I drove it about 75 miles this evening. The misfiring remained steady on #2 and here and there on 1, 5, 6 and 7.  I ran another injector balance test and all but #2 and #3 failed. Doesn't it seem odd that the cylinder that is steadily misfiring continues to pass injector balance tests? O2 sensor data looked normal but there was a noticeable improvement in LTFT on each bank.  I noticed at idle, bank 1 LTFT was about 4 (first time it has been a positive reading since all this started) and bank 2 about -11. However, each time I accelerated to 2K, bank 1 went to -4 to -6 and bank 2 went to -18. The last time I ran the engine, LTFT trims were pretty steady at -23 on bank 1 and -34 on bank 2. So, both of these have improved by driving it even though the misfire and engine light is staying on steady. Maybe the computer has adjusted somewhat for the fuel trims issue. It did throw the P219A code again for some reason and activated the MIL along with P0300.

 

the last time I had the intake off, I switched injectors around in various cylinders. I used 4 of the original injectors that came out of cylinders that were firing well and moved 4 of the best firing ebay injectors into the other 4 cylinders. Unfortunately, I did not write down which ones went in what cylinder, but I did mark each injector as to its origin so when I take it back apart, I will know which ones are which. I have this feeling the 4 ebay injectors may be in the cylinders that are showing the most misfires now (1, 2, 3, 5,). Here are the historical misfires as of tonight:

1   574

2   1828

3   530

4   16

5   86

6   339

7   143

8   20

 

If it isn't raining tomorrow, (yeah, I have to work on it outside in the driveway), I'll be pulling the injectors out again.

[asilverblazer]

On 5/23/2024 at 8:10 PM, ktuck said:

 

... The misfiring remained steady on #2 and here and there on 1, 5, 6 and 7.  I ran another injector balance test and all but #2 and #3 failed. Doesn't it seem odd that the cylinder that is steadily misfiring continues to pass injector balance tests? ... It did throw the P219A code again for some reason and activated the MIL along with P0300.

 

the last time I had the intake off, I switched injectors around in various cylinders. I used 4 of the original injectors that came out of cylinders that were firing well and moved 4 of the best firing ebay injectors into the other 4 cylinders. Unfortunately, I did not write down which ones went in what cylinder, but I did mark each injector as to its origin so when I take it back apart, I will know which ones are which. I have this feeling the 4 ebay injectors may be in the cylinders that are showing the most misfires now (1, 2, 3, 5,). Here are the historical misfires as of tonight:

1   574

2   1828

3   530

4   16

5   86

6   339

7   143

8   20

 

If it isn't raining tomorrow, (yeah, I have to work on it outside in the driveway), I'll be pulling the injectors out again.

I don't think there is a reason to associate a miss firing cylinder #2 to a pass or fail of its injector on the balance test. All the injectors on the bank have to spray the same amount of fuel for the same pulse width. The computer sends a pulse width signal to the all the injectors and expects that each sprays the same specific amount of fuel. Then it uses the O2 sensor data to adjust the fuel trim of that bank to correct the air fuel ratio of that bank, by altering the pulse width signal to all the injectors on that bank. If one injector is out of balance to the others on that bank (whether its good or bad) it will miss fire because it has been leaned out beyond the other injectors. In other words 4 'bad' injectors that fail the injector balance test could still operate fine with no miss fires so long as the PCM can trim the fuel to bring them into proper air fuel ratio via pulse width modulation. If those 4 bad injectors get so bad that pulse width modulation is outside of specification or long term fuel trim is too high/low a code would set to that effect. 

 

If you have to get into it anyways, I'd put all the OEM injectors back in to get a baseline. 

[ktuck]

19 hours ago, asilverblazer said:

I don't think there is a reason to associate a miss firing cylinder #2 to a pass or fail of its injector on the balance test. All the injectors on the bank have to spray the same amount of fuel for the same pulse width. The computer sends a pulse width signal to the all the injectors and expects that each sprays the same specific amount of fuel. Then it uses the O2 sensor data to adjust the fuel trim of that bank to correct the air fuel ratio of that bank, by altering the pulse width signal to all the injectors on that bank. If one injector is out of balance to the others on that bank (whether its good or bad) it will miss fire because it has been leaned out beyond the other injectors. In other words 4 'bad' injectors that fail the injector balance test could still operate fine with no miss fires so long as the PCM can trim the fuel to bring them into proper air fuel ratio via pulse width modulation. If those 4 bad injectors get so bad that pulse width modulation is outside of specification or long term fuel trim is too high/low a code would set to that effect. 

 

If you have to get into it anyways, I'd put all the OEM injectors back in to get a baseline. 

 

I went back and reviewed the fuel system diagnosis procedures and found that I was calculating the injector balance testing incorrectly. The procedure says to compare cylinders on each bank, not from one bank to the other. With that in mind, I went back and recalculated my most recent test and it showed three failing cylinders (1,2,3) compared to six the previously way I did it (1,4,5,6,7,8). It is interesting that 5 of those 6 did not fail when I conducted the testing properly. Only cylinder 1 failed both ways and more significantly, cylinder 2, as the primary misfire offender, did in fact fail this latter test. I couldn't help but notice that the average psi pressure drop was much lower on bank 1 (36.75) compared to bank 2 (56.75). Even with the somewhat improved negative fuel trim numbers, it still seems that the right bank is over fueling. I wonder if it could have something to do with the location of the fuel rail pressure sensor...I think it is on the left fuel rail if I recall correctly? 

 

At any rate, my neighbor has agreed to let me hook up my Autel scan tool to his 2015 Tahoe 5.3L to run some test data. I have often found that observing what normal looks like helps me isolate problems better. His Tahoe runs well and has no current codes or drivability issues. He has the same L83 engine with GDI injection. Meanwhile, I have sent my original injectors out for testing. I hope to have them back by next week sometime. I agree the OEM injectors will be my baseline. The ebay injectors are either counterfeit or not. I'm not going to worry about that now and just remove them from the equation altogether. All the other parts I have replaced so far are OEM and will do so with the injectors if the outside testing reveals any that fail. At this point, I personally am not sure the scan tool fuel injector test is reliable test procedure. My results so far have been inconclusive.

[asilverblazer]

5 hours ago, ktuck said:

I went back and reviewed the fuel system diagnosis procedures and found that I was calculating the injector balance testing incorrectly. The procedure says to compare cylinders on each bank, not from one bank to the other. With that in mind, I went back and recalculated my most recent test and it showed three failing cylinders (1,2,3) compared to six the previously way I did it (1,4,5,6,7,8). It is interesting that 5 of those 6 did not fail when I conducted the testing properly. Only cylinder 1 failed both ways and more significantly, cylinder 2, as the primary misfire offender, did in fact fail this latter test. I couldn't help but notice that the average psi pressure drop was much lower on bank 1 (36.75) compared to bank 2 (56.75). Even with the somewhat improved negative fuel trim numbers, it still seems that the right bank is over fueling. I wonder if it could have something to do with the location of the fuel rail pressure sensor...I think it is on the left fuel rail if I recall correctly? 

 

...At this point, I personally am not sure the scan tool fuel injector test is reliable test procedure. My results so far have been inconclusive.

I think you are closing in on it. With these latest results the failing amount of injectors sounds more plausible (#2 might be the source of the trouble codes and drivability issues). I don't think either bank is actually over fueling at this point, meaning that neither bank is getting too much fuel in the cylinders. One bank might be trimming more than the other, but I wouldn't worry about that until it manifests as a problem.

 

...I suppose one could read a little more into it and look for some correlation between the bank with more trim to the bank with greater average fuel pressure drop...

 

I don't think I would read too much into the average pressure drop across the banks either nor the pressure gauge location. 

 

I also wouldn't doubt the test results of the scan tool. If you can repeat the test and get similar pressure drops per cylinder compared to a previous test, I'd trust the readings.

[Dusty Bottoms]

Just an FYI

 

The shape and size of the letters & numbers on the injector is inconsistent from AC Delco and may not be counterfeit parts.

 

I've just ordered a new AC Delco injector from Autozone part number 19420316.

Part# on the injector is A 12709470, this replaces 12668393.

 

I bought the truck a year ago and it looks like one of the injectors was replaced (see image below of injector still installed in the rail)

 

You can see a variation in the size and shape of the letters and number. The new injector from Autozone, should be genuine AC Delco and the old one has been functioning for more than a year and 18k miles. So, I don't believe it's a cheap Chinese knock-off.

 

So, I'm wondering if AC Delco has variations in their manufacturing.

I noticed a similar variation when I ordered two front wheel speed sensors and the packaging and labeling was slightly different from each other. Which made me suspect one may be a counterfeit, but the sensors are both working fine now for months.

 

 

Edited June 17, 2024 by Dusty Bottoms

[ktuck]

On 6/1/2024 at 10:02 AM, Dusty Bottoms said:

Just an FYI

 

The shape and size of the letters & numbers on the injector is inconsistent from AC Delco and may not be counterfeit parts.

 

I've just ordered a new AC Delco injector from Autozone part number 19420316.

Part# on the injector is A 12709470, this replaces 12668393.

 

I bought the truck a year ago and it looks like one of the injectors was replaced (see image below of injector still installed in the rail)

 

You can see a variation in the size and shape of the letters and number. The new injector from Autozone, should be genuine AC Delco and the old one has been functioning for more than a year and 18k miles. So, I don't believe it's a cheap Chinese knock-off.

 

So, I'm wondering if AC Delco has variations in there manufacturing.

I noticed a similar variation when I ordered two front wheel speed sensors and the packaging and labeling was slightly different from each other. Which made me suspect one may be a counterfeit, but the sensors are both working fine now for months.

 

 

 

Yes, there certainly appears to be some inconsistencies with the fonts, numbers, etc, but I think the primary red flag on these injectors is the very low price compared to dealers and other jobbers. I think the old saying, "if it seems too good to be true, it probably isn't" applies here.  Selling 8 "OEM" injectors at a cost just slightly higher than one normally costs, is not normal. But due to being on a tight, fixed income, I fell for it. Now I'm spending more than if I had just bought genuine GM parts to begin with. It is possible that introducing counterfeit parts (plugs, wires, sensors, and injectors) may be most if not all of my drivability problems. I anxiously await the results of the injector testing.

[ktuck]

I received my injectors back from Injector Experts in Risingsun Ohio. One injector failed their test, and they recommended replacement. They sent me a 3-page document on the all the various testing procedures they did for each injector. It was a most comprehensive test procedure I could tell. Keith Brewer runs the business and I highly recommend him. He spent a good deal of time with me on the phone explaining each test procedure they do, and the necessity of certain tests conducted on GDI injectors. He told me when I receive the injectors back in the mail, to call him and he would explain the results of the tests, especially the one that failed. For GDI injectors, the cost is $25 for each injector which I think is a fair price. The question I had to ask him was did he think the nature of the failed injector was such that it would be noticeable as a misfire under light to moderate load, and he said without a doubt. He said replacing it with a good injector will guarantee the engine will run much better regardless of any other existing issues. The 8 injectors I sent him, were all of the original injectors, I wasn't going to waste my time or his on testing the ebay knockoffs. I have a new OEM injector on order and hope to receive it by tomorrow or Monday. Fingers crossed.

[asilverblazer]

58 minutes ago, ktuck said:

...One injector failed their test, and they recommended replacement. They sent me a 3-page document on the all the various testing procedures they did for each injector... The question I had to ask him was did he think the nature of the failed injector was such that it would be noticeable as a misfire under light to moderate load, and he said without a doubt. He said replacing it with a good injector will guarantee the engine will run much better regardless of any other existing issues. The 8 injectors I sent him, were all of the original injectors, I wasn't going to waste my time or his on testing the ebay knockoffs. I have a new OEM injector on order and hope to receive it by tomorrow or Monday. Fingers crossed.

Sure would like to be able to go way back and see miss fire counts from day 1, instead of chasing a P0300, I wouldn't be surprised if the one failed injector had a noticeable miss fire count higher than the others. 

 

I think you put all the original injectors in plus one to replace the failed one, you'll be good to go!

[ktuck]

I received my new OEM injector today and with high expectations, I installed it. Unfortunately, I cannot tell if the misfire problem is corrected because somehow, I have introduced yet a new problem I have not had before. Apparently, the truck is in limp mode or something. The DIC is stating "engine power is reduced." It is staying in open loop and the idle is quite rough, much worse than when I had the misfires going on. When I rev it above about 900 rpm, it smooths out very nice. Also. 4 new codes have appeared that I have never seen before: P0202, P0205, P0207, and P16E5. I have gone back and double checked everything, especially harness connectors on cylinders 3,5 and 7 and all looks okay. I don't know if the P16E5 relates to the first 3 codes or not. I haven't had chance to look them up yet, I just came in when it got dark. I did attempt to collect some scanner data. One thing I noticed on the scanner, was that cylinder 3, 5, and 7 injector control circuit status does not alternate between "Not Run" and "OK" as the other five cylinders do. Maybe that is a hint, I don't know. Perhaps some of you all have some insight on this for me. The only other factor I might mention, don't think it would matter really, but I had the battery disconnected the entire time I had the injectors sent out for testing and I was in WV. Probably around 12 or 13 days, I think. I generally believe when something like this appears that wasn't doing it before, it is linked to the current work/repair. For the life of me, I can't think of what it might be. I was basically removing the intake, fuel rails and injectors, nothing else. If this is limp mode, is there a way to take it out of limp mode or is it locked in until the condition is corrected?

[ktuck]

10 hours ago, ktuck said:

I received my new OEM injector today and with high expectations, I installed it. Unfortunately, I cannot tell if the misfire problem is corrected because somehow, I have introduced yet a new problem I have not had before. Apparently, the truck is in limp mode or something. The DIC is stating "engine power is reduced." It is staying in open loop and the idle is quite rough, much worse than when I had the misfires going on. When I rev it above about 900 rpm, it smooths out very nice. Also. 4 new codes have appeared that I have never seen before: P0202, P0205, P0207, and P16E5. I have gone back and double checked everything, especially harness connectors on cylinders 3,5 and 7 and all looks okay. I don't know if the P16E5 relates to the first 3 codes or not. I haven't had chance to look them up yet, I just came in when it got dark. I did attempt to collect some scanner data. One thing I noticed on the scanner, was that cylinder 3, 5, and 7 injector control circuit status does not alternate between "Not Run" and "OK" as the other five cylinders do. Maybe that is a hint, I don't know. Perhaps some of you all have some insight on this for me. The only other factor I might mention, don't think it would matter really, but I had the battery disconnected the entire time I had the injectors sent out for testing and I was in WV. Probably around 12 or 13 days, I think. I generally believe when something like this appears that wasn't doing it before, it is linked to the current work/repair. For the life of me, I can't think of what it might be. I was basically removing the intake, fuel rails and injectors, nothing else. If this is limp mode, is there a way to take it out of limp mode or is it locked in until the condition is corrected?

 

Another thing I see on my scanner...it shows the fuel rail pressure sensors (both 1 and 2) reading 95057.74 psi. Is this perhaps a result of limp mode status? No way the injectors can handle that kind of pressure. Whatever it is, it has affected all of the left bank except cyl 1, that seems odd to me. The new OEM injector is in the 7 hole and all the other injectors were recently tested and passed by an outside facility.