In this video I have a look at a 2004 Chevrolet 1500 that has had the parts cannon unloaded on it! Injectors, MAF, MAP, fuel pump, plugs, wires, you name it they changed it! Now we need to find out what the real causes are for the negative fuel trims and rich codes. Put down the parts cannon and follow the facts folks. -Enjoy!
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Hey there, viewers and welcome back to the south plain auto channel got a 2004 chevrolet. It's a half ton uh, it's got the big 4.8 in it money lights on and the guy tells me it has rich code. So i think it's a 172 175 po. 172.

175 uh, if i remember correctly, could be wrong. Uh he's been battling this out. They've done injectors saw all your stuff, everybody would do. You know fuel pump and pressure regulator and injectors mass airflow and oxygen sensors purge valve map sensor.

They changed it all, and here we are now. I will say this: i fired this pick up to bring it in and it blew the biggest blue cloud of oil smoke. I'd ever seen in my life - and he warned me so it's been doing that for a long time forget about it. So i did, but it was pretty thick uh in the downtown area here with uh blue haze, uh chevy smoke got the old all-tail hooked up.

They're gon na let it go through a fault, scan uh, we'll see where we're at, and i do see and smell the frustration under the hood here and then we'll just base our diagnosis off the facts that we find along the way. She's all done. Let's see here, 172 175, so rich bank, one bank, two restraint codes, hvac codes, all right great well, so let's go look at some live data, um just kind of gather some yeah there's some stuff here. Let's see we're gon na go right in here and look at fuel trims uh see if there's anything coolant.

Temp we're gon na want to look at coolant. Temp engine speed intake air, anything that that can make it run. Rich uh we're gon na want map, and here oh that's, wrong. I'll tell you that's wrong right now.

Uh barometric pressure is wrong. That could be a problem. Let's see oxygen, sensors yeah, we can grab those make sure everything's good get our fuel trim. So, let's fire this pig up all right, i'm gon na! Take it a minute here: uh did we get the loop status? Okay, i think this is everything that's going to be important.

I know shining the camera at this screen is not ideal, but it's what we have to work with folks, so we're going to let it run a little bit here. This really has me concerned. That's interesting too. Our mass air flow seems to be abnormally high, we'll let the idle come down as it warms up here.

Our fuel trims already starting to make some correction, especially on bank one. That's interesting. It's trying to pull back fuel still an open loop oxygen sensors seem responsive, except for this guy seems still kind of at its bias. Voltage, not a big deal.

Mass airflow definitely seems too high. So this is concerning this is concerning. So that's very interesting. Fuel trims are pegged out.

I think i hear a vacuum leak. Human yeah. I definitely hear a vacuum leak and it's on this purge valve. I don't know, i doubt the camera's picking up, but i can it's quite obviously making some sucky sucky sound there.

I assume, because it's missing the rest of whatever goes under, that bolt shouldered bolt. That's not going to make a lean or a rich condition, and so right now fuel trims are pegged out short-term long-term, that's really bad coolant. Temp looks okay. Mass airflow is definitely over reporting remanufactured junk.
Let me grab a light. Yeah map sensors aftermarket purge solenoids aftermarket mass airflow, some remanufactured garbage. Well, we got a good place to start folks i'll. Tell you what folks known good.

I got a map sensor here for chevrolet. I believe on these kion engine off. Our map is also our barrel, which it should be. You know so.

Kion engine off manifold pressure should be barometric pressure, so we could test, but i need to get a step stool. We could test that uh current map sensor or we can take five seconds and plug this in, because that's quicker than testing i'm gon na unplug that one i'll plug that little guy in i'm going to turn the key back on we're going to see what barometric Pressure is go back in here back into our field. Trim, we'll probably have to pick out our list again. Uh, we'll just go right to barrow, where it was down towards the bottom boom.

Look at that 14.07, not 12 psi. So that's a problem! Great! I tell you what let's be: let's be, mr nice guy, you think i'm a nice guy in this, though huh yeah i can be, or i am i'm a pretty nice guy right most of the time i miss though, when i'm not being pretty what'd. You say: trinity what'd, you say: gosh we've got to use the uh little rubber here. Folks, mine didn't have one on it.

Stick that in there oh good, keep that in there all right guess what else i got folks mass airflow for a chevy huh. Where is this guy got stuff kicking around? We got to get rid of the remanufactured junk here. What's interesting, is the amount of parts that they've thrown at this vehicle to fix a problem that they still have? I don't know it's hard to explain. I assume that this thing got injectors and oxygen, sensors and mass airflow and maps and all the parts that it got because of this problem.

Now i could be wrong. I didn't uh, i didn't quiz them that heavily on it. Maybe this these parts were changed to fix another problem, but created this problem so yeah, that's obviously uh some kind of remand. I've just got the old rusty, krusty oem, which is always better than remand remand mass airflow sensors.

Usually you need to buy them by the dozen. So, let's see we'll slip this one in i'm pretty sure this is a good one. Famous last words: that's not something you want to hear from your heart transplant, doctor gosh, okay, hopefully it's the right one. I think i think these are the same.

Like 99. 506 somewhere he's in there, it's got to be all right, just fired it up. Let me get the same. Let me move you around we're going to get the same data that we can now i could.

We could be totally wrong in this by we i mean us, but we got to be getting better. So barrow's good map looks good. Let's hit our mass airflow engine speed's still up there, a little high she's still cutting back on the uh, that's pretty wild. I would have thought we would have made better corrections by correcting the barometric pressure, but she's still cutting it back.
Let me unhook the purge zone right here. Just want to make sure it's not pulling in fuel vapors very interesting here, folks, uh, very interesting, all right. So that's pretty interesting. Folks, uh map is working correctly.

Now the idle has come down. Mass airflow is working correctly, uh, correct readings, there's no fuel being drawn in from the purge, which is a possibility. You know: where can we get this extra fuel uh things we have to think of are also oil? How contaminated is the oil you know drawing through the pcv system? You know past the rings. Obviously, this engine is a massive oil burner.

You know, so that's something. We have to think of also kind of keep here in our back pocket. I did remove the pcv hose right here right off the intake plugged it off it only changed it. Four or five percent went from 30 to, like you, know, 25 percent uh.

So it's not all coming from there, so this is pretty interesting. Now the things we have to uh other things we have to think of too is you know, fuel pressure is fuel pressure too high. You know there's been so many parts thrown at this thing could have wrong injectors in it. For all i know um, i don't think this is flex fuel never had an issue with the older ones, with the flex fuel sensors.

I think that were underneath. I don't really know how they function. If that can be uh, you know if that can screw something up. Also, that's something we got to think about.

Rich codes are not that common and when they are it's typically over reporting mass airflow purge valve stuck open. Some common stuff, so i'm pretty surprised to see some things that are broken and reading incorrectly that ultimately haven't made a poo of difference. So let's do this here, fellas the truck's pretty rough. I just looked underneath it.

There is not much left to it um. So i don't know how much time we'll invest into it. That's always up to the customer but see if it's a little bit of a baseline, what's happening here. Let's uh see where we're at with fuel pressure.

Let me just turn the key on and we'll just kick the pump on, i'm just turning the key on there when it's about 40 40 to 45 expect this thing to be about 50 running. Okay: let's go ahead and fire it up about 50 psi running! That's what i would expect that doesn't appear to be abnormal, and i guess the other thing that's uh noteworthy is the fact that it holds pressure about 45 psi. So that seems to be good. Um i'll, tell you what you grab a rag here.

I didn't uh. Let's just give a little whiff shall we, of course now my hands are soaking. Yes, go like this: it's not over full! It's down about a quart typical gm! You smell it. It just smells like oil.
Doesn't smell super gas soaked, so this is interesting. So the only unknown variable here are the injectors. Now i see they must be of the best chineseium. There is no numbers, no identifiers, no nothing on those injectors.

That can help me to tell whether or not they are the correct ones. Um they sell. You know a lot of this crap on ebay and stuff, where you know you get 32 injectors for a nickel and you know guaranteed to fit your vehicle. I'm going to have to think about this for a minute folks.

I think we're running out of options running out of logical things that can cause or induce a rich condition to this degree: unwanted fuel from the purge incorrect map sensor, skewed mass air flow fuel pressure too high um pcv system pulling in vapors, making it run rich Or just base engine mechanical uh, where it's pulling, you know tons of tons of oil past the rings and which you know like. I say this thing ripped a big cloud of smoke. It's not blowing big clouds of smoke sitting here, uh even prior to the catalytic converter heating up. So i'm a little doubtful uh about that about base engine mechanical.

You know, causing you know, an induced rich condition to this degree on both banks, i'm gon na shut the camera off. I'm gon na think i'm gon na do some poking. I'm gon na ask google what's wrong with it, see what she says and then i'm gon na talk to the customer, probably before all of that to ask them when the injectors came into the loop here in an effort to fix this problem or where they put In and then this problem was created, that's that's going to be a key piece of evidence and then a customer. Where did you get them and do you have a part number so we can verify.

I think we're on that road. One other thing that can be a concern. Folks is software: do we have the correct calibration id numbers per vin? I went on gm cal ids site here to make sure everything coincided the vin number versus what gm says. It should be program calibration numbers, cvn numbers and everything matches, so it is the correct software for this truck and for that engine so that that's always a concern also can't get a hold of the customer folks um, and i can't think of anything else that would Induce a rich condition: i really want to go down to wilbur to pull the bath, who doesn't sponsor our show and just grab a whole fuel rail and just pop it on here, just to see um injectors newer about 100 bucks, a whack.

You know if you get legitimate good ones, you know like i say they got the fleabay ones, but i'd really like to know the series of events here, because it's quite peculiar that we've got the problem on both banks and we had some issues that we corrected, Which is weird also, i need to make a decision. Kaboom just like that. Went down to wilbur still won't sponsor us, and i got these. I didn't have time taking long bit of a hurry.
I did call chevrolet with the bin number of the vehicle that i took these injectors off and had them run this vid number for the vehicle that we're going to put these on in about a half. A second same number. Stick around modern television. Great you don't have to sit through the boring repairs of swapping out injectors, so they're in they're tightened up.

I think everything's good fuel lines. Oh, you know what safety! Third, where is it right here almost forgot this? That would have been catastrophic in the event that this blows apart, there's that i think everything else is plugged in and hooked up. Okay, let's uh cycle. The key here folks could be wrong still, but i got my suspicions, let's make sure fuel's not going pee-pee everywhere.

I don't smell it, let's see how she starts now, let's go. Have a look at beta fuel trim: hey what do you know? What do you say huh, that's what happens when you put cheap junk chinese injectors in them from the ebay. I say we're fixed mass airflow engine coolant, temp engine speed map barrel. You got ta, follow the facts folks, so i never did get a hold of this guy.

So i couldn't be burning myself because i didn't get authorization to fix this. So if he tells me to pound sand, guess what i'm out some money and some time wouldn't be the first time, though, because i know you guys wanted closure and if i told you that i suspected that the injectors are the only thing left, you wouldn't have Believed me interesting that our mass airflow is still slightly high, but not enough to cause a problem better than eight grams. The old one was uh, but our fuel trim says it all. This engine is running absolutely perfect.

We are as close to zero as this old chevrolet is going to get with the miles and stuff. That's on it, plus the amount of fuel. That's probably in the oil i'm happy, and i call it a fix. These are uh, that's something on there.

Moto most plus m-o-s-t, plus, i believe, is what it says: uh nothing i've heard of before. I think that's what it says: m-o-s-t yeah, m-o-s-t, plus something i'll tell you where they are right now, j-u-n-k junk. I hope you all understand uh what has happened and the series of events we took to get to where we're at barometric pressure was screwed up because of the map sensor, which is where it reads barrel from kion engine off the pcn looks and says: hey, you Know where you at here here i am, this is the elevation i'm at and, of course it takes those calculations also uh during driving. I think it takes them during wide open throttle events, perhaps so, let's say you're up in the rockies and you're down here in the rockies and you're going to get up here in the rockies.

Well, the you know, the elevation difference is whatever the difference is, and you know you're giving the chevy the full throttle on the way up, and it may take some calculations from that. I know ford. Does that and they calculate barrel through the mass airflow, i'm not sure gm strategy, i'm just making stuff up right now, but that's what i would suspect some of them have. They can sense barrel inside the pcm.
I think honda's, pretty pretty uh famous for doing that. Having the barrel sensor built into the pcm instead of using map, but i think they also make them relative comparison. So key on engine office says: hey, you know: does the boost sensor match the map sensor which matches the barrow sensor so they'll use it for some redundancy like hey, you know. If one of these fails, it might flag a code and then use a default strategy of one of the other sensors.

So keep that in mind. Mass airflow is obviously skewed a little. I'm i'm just gon na we're gon na keep that one in there we're gon na keep the oem in there. We're gon na keep that map sensor in there and then obviously the ultimate fix with our fuel trims here uh, as we can still see our beautiful worthy fuel injectors.

If you want to see some videos on field trim and how to understand it, i think wells, electronics or wells ve, ngk now mike becker over there. I think he does some great videos on fuel trim. Uh, you know, go over there check out their channel. Sometimes we just jump into it because we can't explain each thing as we go, even though i sit here, rambling at the end got ta call this guy see if he wants to fix now.

Shame on me, but at least you know, i got ta put all his little junk parts back in at least we know when he wants the job done uh, but we won't do that. I'd really just give it to him, then put the whole crap back on, because we know, and what i do know is. I want you to go in the comments section. The comments, the concerns, the facebook, the bell ringing, the insta the subscribe button.

Whatever else you do when you're there and just remember, if you're responding to it, you can do it thanks for watching bonus footage, i got one of these was at the junkyard too, and this is what is missing off the perch. It just goes on the bottom. It's a hunk of rubber because it uses a shoulder pull and we should resolve our sealing issue that we have down here so we'll put that shoulder bolt in there and actually have something to hit against now. Anyhow, for what it's worth,.


By EricO

16 thoughts on “Parts cannon special: rich running chevy truck p0172 and p0175”
  1. Avataaar/Circle Created with python_avatars Eddie Reichel says:

    Had a customer bring his old chivy in one day and asked me to figger out what was wrong. It was misfiring fierce. Injector Ballance showed 2 bad injectors. He said well I have some in the truck 29.99 from ebay. The brand name was "engine dancer"

  2. Avataaar/Circle Created with python_avatars Tony thompson says:

    Yeah your right Eric O they Just recently transplanted a pig heart into a man an they new it wasent going to work an you guest it the man died you can't trust the doc no more the money is the bottom line your life does not matter anymore

  3. Avataaar/Circle Created with python_avatars f150 man says:

    I have an 08 with the big 5.3 she likes to blow oil smoke under full acceleration Burns a quart a month or so it's what they do

  4. Avataaar/Circle Created with python_avatars Leon Busteed says:

    I love how the guy and from your work likely spent many hours and likely about $800+ but the truck has massive rust (at least in the front fender). My parents are from the west side of Stuben County and from visits there know it is rust central.

  5. Avataaar/Circle Created with python_avatars Filecabinet says:

    We had a guy bring in an outboard where his "mechanic" replaced nearly everything chasing a run issue. We have since spent almost a year replacing aftermarket components 1 at a time as they have failed.

  6. Avataaar/Circle Created with python_avatars Antonio Claudio Michael says:

    Nice find on the cheap injectors being the issue since you installed a used fuel rail and Injectors Eric O runs great now @SouthMainAutoRepairLLC

  7. Avataaar/Circle Created with python_avatars Thomas Fletcher says:

    Nothing like the good ol " chineseum " ( which is most likely a branch of your favorite , dorman ) to totally mess up an engine

  8. Avataaar/Circle Created with python_avatars wino99999 says:

    Good job! Hope your customer appreciates what you've done for him! And he doesn't fire the chinesium at his truck with such abandon in future!

  9. Avataaar/Circle Created with python_avatars Rj Aquaponics says:

    Junk in, Junk out. The guy has nobody to blame, but himself. Perhaps he set this up for failure, but you proved him wrong. Loved to heard the call!

  10. Avataaar/Circle Created with python_avatars Michael Bazinet says:

    More shops need to think outside of the box like you did on this. Great work Mr.O. it's really enjoyable to learn from you !

  11. Avataaar/Circle Created with python_avatars Kim Berg says:

    Amazing! You never disappoint your viewers. You say you aren't the best, i beg to differ. I saw you scrathin your noggin thinking real hard, power of deduction! Love it. Thank you for being you! Now if you can recommend a good Suzuki mechanic my day would be complete…lol

  12. Avataaar/Circle Created with python_avatars Memphis Applegate says:

    No, wrong again. I hate to keep correcting you! You can do it, but I can't do it, and those other shops that worked on this truck couldn't do it either!!! Just kidding of course, as you are the MAN.
    I sure would like to see you diagnose, like a Model A, or even a 1950's car with no sensors, or computers, etc.
    I must admit that I sometimes skip the "break Jobs," or the "muffler" jobs, etc., but I never miss your diagnostics videos – fact is, I sometimes go back and watch old diagnostics videos again. I guess this makes up for the break jobs I miss.
    BZ

  13. Avataaar/Circle Created with python_avatars hightttech says:

    I have a box of pullout, aftermarket, DIY installed injectors with all sorts of problems. I've received a few NEW defects as well (mostly leakers). THUS, I will NOT install a set without flow testing on the bench first. PERIOD.

  14. Avataaar/Circle Created with python_avatars Ryan Tinney says:

    Another great video. You do the industry a terrific service by making these videos that people will refer to for years to come.

  15. Avataaar/Circle Created with python_avatars Sylvain Laberge says:

    Awesome video as always! With what customer saved on injectors, perhaps he can go and buy a leaf blower…

  16. Avataaar/Circle Created with python_avatars JORDAN VARGOVICH says:

    People think they r doing themselves favors by buying cheap parts. Ends up costing u more in the long run

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