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Post by treetop on Feb 7, 2023 18:26:55 GMT -5
Anybody have any ideas
2010 2500 4 wheel drive Chevy truck
Says lean bank one lean bank two on scan
Truck runs fine no issues regardless of speed with no load even when your standing on it hard
I hook my trailer to it with weight in it and it falls on its face going up hills the faster you go the worst it gets it almost seems like it’s got 25 30 percent less HP
Fuel pressure checks fine did normal checks on air filters and stuff
I’m not talking about small rises but a decent hill
Running 75 mph at base of hill by the top lucky to run 65 68 and it down shifts and is running around 3500 to 4000 RPM that’s above normal unless it’s a huge hill it’s not missing or any backfire
I’ve owned this truck since new something is wrong I use to pull the same trailer but it was 16 foot this one’s 12 so it should pull the same or easier
The other odd thing is the check engine light comes on stays on but if I park the truck for a few days it goes off on it’s own
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Post by greghopper on Feb 7, 2023 19:14:40 GMT -5
Sounds like it could be sucking air around manifold or vacuum leak….I wouldn’t rule out a sensor also.
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Post by deadeer on Feb 7, 2023 19:30:58 GMT -5
Could be a number of things. Meaning is that the O2 sensor is reading a lean burn condition. As said, could be vacuum leak, or weak fuel supply, caused by clogged fuel filter, clogged injector, weak fuel pump (could have good psi but low volume, could have split/cracked hose or connector in tank from fuel pump, had it happen to me!), or mass air flow sensor reading wrong. I'd take to a reputable shop where somebody can read a real scan tool and decipher the values. Will save time and money on guessing.
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Post by treetop on Feb 7, 2023 19:48:26 GMT -5
Could be a number of things. Meaning is that the O2 sensor is reading a lean burn condition. As said, could be vacuum leak, or weak fuel supply, caused by clogged fuel filter, clogged injector, weak fuel pump (could have good psi but low volume, could have split/cracked hose or connector in tank from fuel pump, had it happen to me!), or mass air flow sensor reading wrong. I'd take to a reputable shop where somebody can read a real scan tool and decipher the values. Will save time and money on guessing. That’s the plan they tell me it’s probably a mapping sensor I’ve tried to find vacuum leaks but not found anything thing that stands out, To be honest I really don’t know what a mapping sensor is but they tell me it reads load vrs fuel and to me driving that’s what I told them it fills like I run out of gas it’s like going from a V8 to a V6 motor |
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Post by bowonlykindofguy1 on Feb 7, 2023 19:49:02 GMT -5
Could be a number of things. Meaning is that the O2 sensor is reading a lean burn condition. As said, could be vacuum leak, or weak fuel supply, caused by clogged fuel filter, clogged injector, weak fuel pump (could have good psi but low volume, could have split/cracked hose or connector in tank from fuel pump, had it happen to me!), or mass air flow sensor reading wrong. I'd take to a reputable shop where somebody can read a real scan tool and decipher the values. Will save time and money on guessing. 100% agree. Does it have egr? What about the feature where it drops cylinders from 8 to 6 or 4 at cruise? But honestly my gut is screaming fuel pressure or volume is low. High load such as climbing your steep hills will increase load on engine which requires more fuel to maintain the power needed. If not enough power is being made transmission will stay in lower gear to make it to the top. |
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Post by treetop on Feb 7, 2023 19:59:06 GMT -5
I thought the same maybe a bad pump or filter but I’ve ran the truck hard I’ve cranked it up hard good thing the law wasn’t around it never stumbles until it’s under hard load I’ve plowed snow with it this year and it never showed up lot of weight but 15 20 mph is tops plowing
IDK will see what they come up with
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Post by greghopper on Feb 7, 2023 20:04:19 GMT -5
Could be a number of things. Meaning is that the O2 sensor is reading a lean burn condition. As said, could be vacuum leak, or weak fuel supply, caused by clogged fuel filter, clogged injector, weak fuel pump (could have good psi but low volume, could have split/cracked hose or connector in tank from fuel pump, had it happen to me!), or mass air flow sensor reading wrong. I'd take to a reputable shop where somebody can read a real scan tool and decipher the values. Will save time and money on guessing. That’s the plan they tell me it’s probably a mapping sensor I’ve tried to find vacuum leaks but not found anything thing that stands out, To be honest I really don’t know what a mapping sensor is but they tell me it reads load vrs fuel and to me driving that’s what I told them it fills like I run out of gas it’s like going from a V8 to a V6 motor Sometimes you spray carb cleaner or starting fluid around vacuum hose or intake and idle will go up or down if it has a leak. |
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Post by deadeer on Feb 7, 2023 20:10:36 GMT -5
That’s the plan they tell me it’s probably a mapping sensor I’ve tried to find vacuum leaks but not found anything thing that stands out, To be honest I really don’t know what a mapping sensor is but they tell me it reads load vrs fuel and to me driving that’s what I told them it fills like I run out of gas it’s like going from a V8 to a V6 motor Sometimes you spray carb cleaner or starting fluid around vacuum hose or intake and idle will go up or down if it has a leak. I've also seen an old timer use a propane torch turned on but not lit obviously to accomplish same. Typically a vacuum leak will raise engine rpm depending how severe. Sounds like it's kinda minuscule since only under hard load. But it sure doesnt take much. I'm betting fuel starvation of some sorts. |
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Post by deadeer on Feb 7, 2023 20:11:14 GMT -5
Could be a number of things. Meaning is that the O2 sensor is reading a lean burn condition. As said, could be vacuum leak, or weak fuel supply, caused by clogged fuel filter, clogged injector, weak fuel pump (could have good psi but low volume, could have split/cracked hose or connector in tank from fuel pump, had it happen to me!), or mass air flow sensor reading wrong. I'd take to a reputable shop where somebody can read a real scan tool and decipher the values. Will save time and money on guessing. 100% agree. Does it have egr? What about the feature where it drops cylinders from 8 to 6 or 4 at cruise? But honestly my gut is screaming fuel pressure or volume is low. High load such as climbing your steep hills will increase load on engine which requires more fuel to maintain the power needed. If not enough power is being made transmission will stay in lower gear to make it to the top. EVERYTHING has EGR nowadays. |
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Post by treetop on Feb 7, 2023 20:12:28 GMT -5
Could be a number of things. Meaning is that the O2 sensor is reading a lean burn condition. As said, could be vacuum leak, or weak fuel supply, caused by clogged fuel filter, clogged injector, weak fuel pump (could have good psi but low volume, could have split/cracked hose or connector in tank from fuel pump, had it happen to me!), or mass air flow sensor reading wrong. I'd take to a reputable shop where somebody can read a real scan tool and decipher the values. Will save time and money on guessing. 100% agree. Does it have egr? What about the feature where it drops cylinders from 8 to 6 or 4 at cruise? But honestly my gut is screaming fuel pressure or volume is low. High load such as climbing your steep hills will increase load on engine which requires more fuel to maintain the power needed. If not enough power is being made transmission will stay in lower gear to make it to the top. This truck is a straight 8 it doesn’t drop from 8 to 6 the transmission seems to be working right it’s a 5 speed with overdrive it seems worse running the overdrive gear vrs standard drive |
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Post by deadeer on Feb 7, 2023 20:19:55 GMT -5
100% agree. Does it have egr? What about the feature where it drops cylinders from 8 to 6 or 4 at cruise? But honestly my gut is screaming fuel pressure or volume is low. High load such as climbing your steep hills will increase load on engine which requires more fuel to maintain the power needed. If not enough power is being made transmission will stay in lower gear to make it to the top. This truck is a straight 8 it doesn’t drop from 8 to 6 the transmission seems to be working right it’s a 5 speed with overdrive it seems worse running the overdrive gear vrs standard drive She had a tune up in awhile? You should have the motor out of my 03. I swear it was hopped up before I got it. Way more power than it deserves for a 5.3. It spins 285's with posi like nobody's business. The body and frame are rusting bad, but the drivetrain is still killer. |
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Post by esshup on Feb 7, 2023 23:07:42 GMT -5
He just needs to swap the motor for a 6.7L Cummings motor.  |
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Post by treetop on Feb 8, 2023 5:56:25 GMT -5
Could be a number of things. Meaning is that the O2 sensor is reading a lean burn condition. As said, could be vacuum leak, or weak fuel supply, caused by clogged fuel filter, clogged injector, weak fuel pump (could have good psi but low volume, could have split/cracked hose or connector in tank from fuel pump, had it happen to me!), or mass air flow sensor reading wrong. I'd take to a reputable shop where somebody can read a real scan tool and decipher the values. Will save time and money on guessing. 100% agree. Does it have egr? What about the feature where it drops cylinders from 8 to 6 or 4 at cruise? But honestly my gut is screaming fuel pressure or volume is low. High load such as climbing your steep hills will increase load on engine which requires more fuel to maintain the power needed. If not enough power is being made transmission will stay in lower gear to make it to the top. That’s the odd thing one would think low fuel or pressure but it runs around 2100 to 2400 RPM pulling when it drops gears it will go to 3500 or more one would think your using more fuel but it runs up the hill it’s screaming but it makes it I realize the lower gear is helping but your still should be dumping more gas in to dang near double the RPM IDK it’s going back in they dumped the fuel mapping and reloaded it at least I believe that is what they tried to tell me. Like I said the the check engine light goes out on its own I thought it kept the code but it’s gone every time I make it to the dealer I got the code myself one of the guys I work with has a used scanner he bought off a mechanic for his own cars |
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Post by bowonlykindofguy1 on Feb 8, 2023 6:29:51 GMT -5
100% agree. Does it have egr? What about the feature where it drops cylinders from 8 to 6 or 4 at cruise? But honestly my gut is screaming fuel pressure or volume is low. High load such as climbing your steep hills will increase load on engine which requires more fuel to maintain the power needed. If not enough power is being made transmission will stay in lower gear to make it to the top. EVERYTHING has EGR nowadays. vct systems replaced a lot of true egr systems. Does the same thing without the egr valve |
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Post by esshup on Feb 8, 2023 9:09:25 GMT -5
100% agree. Does it have egr? What about the feature where it drops cylinders from 8 to 6 or 4 at cruise? But honestly my gut is screaming fuel pressure or volume is low. High load such as climbing your steep hills will increase load on engine which requires more fuel to maintain the power needed. If not enough power is being made transmission will stay in lower gear to make it to the top. That’s the odd thing one would think low fuel or pressure but it runs around 2100 to 2400 RPM pulling when it drops gears it will go to 3500 or more one would think your using more fuel but it runs up the hill it’s screaming but it makes it I realize the lower gear is helping but your still should be dumping more gas in to dang near double the RPM IDK it’s going back in they dumped the fuel mapping and reloaded it at least I believe that is what they tried to tell me. Like I said the the check engine light goes out on its own I thought it kept the code but it’s gone every time I make it to the dealer I got the code myself one of the guys I work with has a used scanner he bought off a mechanic for his own cars High RPM light load uses less fuel than when a heavy load is on the motor, almost irregardless of rpm. If you have the codes that were thrown, put them up here and I'm sure at least one of us can tell you what they mean. |
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Post by jman46151 on Feb 8, 2023 9:29:16 GMT -5
Could be a number of things. Meaning is that the O2 sensor is reading a lean burn condition. As said, could be vacuum leak, or weak fuel supply, caused by clogged fuel filter, clogged injector, weak fuel pump (could have good psi but low volume, could have split/cracked hose or connector in tank from fuel pump, had it happen to me!), or mass air flow sensor reading wrong. I'd take to a reputable shop where somebody can read a real scan tool and decipher the values. Will save time and money on guessing. Best answer so far. You can check the things he mentioned or take it in somewhere so they can read fuel pressure and check the individual injectors. Don't discount the MAF sensor. I recently cleaned mine in my commuter car and it made a big difference. Just make sure you buy the specific cleaner for it. |
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Post by treetop on Feb 8, 2023 13:35:02 GMT -5
Could be a number of things. Meaning is that the O2 sensor is reading a lean burn condition. As said, could be vacuum leak, or weak fuel supply, caused by clogged fuel filter, clogged injector, weak fuel pump (could have good psi but low volume, could have split/cracked hose or connector in tank from fuel pump, had it happen to me!), or mass air flow sensor reading wrong. I'd take to a reputable shop where somebody can read a real scan tool and decipher the values. Will save time and money on guessing. Best answer so far. You can check the things he mentioned or take it in somewhere so they can read fuel pressure and check the individual injectors. Don't discount the MAF sensor. I recently cleaned mine in my commuter car and it made a big difference. Just make sure you buy the specific cleaner for it. The problem is the dang check engine light goes away and it is not saving the code I had the scanner in the truck and did it and than told dealer what it was All the trucks vans I’ve owned and it’s been a lot with work I’ve never seen a check engine light go back off on it’s own Most of the stuff said has been checked other than dropping tank to check pump and filter They are putting in a fuel mapping sensor I have no idea what that is but they believe it maybe the issue |
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Post by treetop on Feb 8, 2023 13:38:37 GMT -5
That’s the odd thing one would think low fuel or pressure but it runs around 2100 to 2400 RPM pulling when it drops gears it will go to 3500 or more one would think your using more fuel but it runs up the hill it’s screaming but it makes it I realize the lower gear is helping but your still should be dumping more gas in to dang near double the RPM IDK it’s going back in they dumped the fuel mapping and reloaded it at least I believe that is what they tried to tell me. Like I said the the check engine light goes out on its own I thought it kept the code but it’s gone every time I make it to the dealer I got the code myself one of the guys I work with has a used scanner he bought off a mechanic for his own cars High RPM light load uses less fuel than when a heavy load is on the motor, almost irregardless of rpm. If you have the codes that were thrown, put them up here and I'm sure at least one of us can tell you what they mean. Your right but I’m talking with trailer hooked at lower and higher RPm |
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Post by treetop on Feb 8, 2023 14:03:58 GMT -5
Maybe I’m still saying it wrong one would think at a higher RPM under load it would be even worse but it’s not the truck will pull it up the hill
This is the thinking I have along with dealer if it’s a pump vacuum filter injection problem it would show up even more when it down shifts trying to maintain speed when it down shifts it will actually pick speed up not real fast but it will come back up
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Post by deadeer on Feb 8, 2023 20:08:10 GMT -5
How many miles Dave? Maybe its geting tired from plowing? 5.3? Mines got 189k and its stronger than hell, but its lived a charmed life.
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