My 04’ smokes a lot at idle. It’s not always consistent, sometimes it will smoke a lot and sometimes it is just a very thin haze. Truck dose run perfectly with no symptoms of anything wrong. In the past two years I have installed a new turbo, new injectors, and new fuel filter housing. Oil change, air filter and fuel filter are changed twice a year regardless of how much I drive it. Any ideas of what it could be??
04’ Lb7 smokes a lot at idle
- Thread starter Inkram
- Start date
Fill out your sig so we know what we’re looking at. Any tuning? If stock, likely an injector issue. Have you checked balance rates?
I don’t remember what brand of injectors I had put in, they are stock replacements. The smoke started before the new injectors and hasn’t changed.
if pensacola rings a bell then it's time for new injectors. if you got them from a reputable vendor then perhaps installation contamination on the new injectors.
and as mentioned above, get us the balance rates and main fuel rate. Baro, MAF, desired and actual fuel pressure would be good too. and if you can, maybe even do a compression test
and as mentioned above, get us the balance rates and main fuel rate. Baro, MAF, desired and actual fuel pressure would be good too. and if you can, maybe even do a compression test
Sounds exactly like a bad LB7 injector, or exactly as my bad LB7 injector anyway.
If you're positive that it smells like diesel, there's only a couple other possibilities. You could have a cylinder low on compression, but then you'd likely have other symptoms (down on power, fuel mileage, etc.). It could also be a fuel pressure problem (either CP3, regulator, or tuning), but again there would probably be other symptoms (rough idle, hard to start, etc.).
As mentioned already, some simple OBD2 diagnostic values would help narrow it down a lot (balance rates, main fuel rate, fuel pressure). If you don't have a scanner, you could probably get Advance or Autozone to pull them for you. Needs to be done with the truck at operating temp, in park, at idle, and with the A/C off.
If you're positive that it smells like diesel, there's only a couple other possibilities. You could have a cylinder low on compression, but then you'd likely have other symptoms (down on power, fuel mileage, etc.). It could also be a fuel pressure problem (either CP3, regulator, or tuning), but again there would probably be other symptoms (rough idle, hard to start, etc.).
As mentioned already, some simple OBD2 diagnostic values would help narrow it down a lot (balance rates, main fuel rate, fuel pressure). If you don't have a scanner, you could probably get Advance or Autozone to pull them for you. Needs to be done with the truck at operating temp, in park, at idle, and with the A/C off.
bad cup doesn't leak fuel into the cylinder. there is only coolant around it. so if it leaks then it will pressurize the coolant system and leak coolant into the cylinder when off
I would agree with other comments, I think it may be time for a set of injectors. Depending on the brand I've seen them be bad out of the box, fail in 1-5 months, or fail a year later as it's simply unknown with some of the crap companies. There are quite a few good companies out there, just have to know which ones to pick.
Do you really want (or need) an answer to that?
Reviving an old thread instead of creating a new one.. I have been trying to determine if my injectors are going bad (I am new to diesels (Only had my current truck a little over a year).
I have an 04 silverado 2500 with the lb7. I am getting white smoke at idle.. but even more when in reverse/drive. Reverse is the worst offender in terms of smoke volume.. Drive is hit or miss.. some days its pretty bad (at traffic lights and such) and other days not so bad. In neutral/park its hit or miss.
The smell is pretty distinctly diesel, no fuel in oil and no other symptoms (No power loss, no rough idle, no long cranking to start, etc). I did recently replace the fuel pressure regulator (I forget what its actually called.. replaced it just after Christmas)
I had access to a scanner for about 15 minutes the other day to check for balance rates and such (Are there any decent scanners in the sub $500 category? I got to use a snap on... but I don't have the money to buy one)
Here are a few videos I was able to take to get the data I see people requesting here:
Vid 1:
Source: https://youtu.be/YKNauC7lrqg
Vid 2:
Source: https://youtu.be/n3gSynK2B6M
Vid 3:
Source: https://youtu.be/1gulnw2WW4g
Vid 4:
Source: https://youtu.be/RG7Et7rG82c
While checking for these values the truck was 'cold' and only got to run about 10 minutes, not sure how much that hurts/helps the data.
Balance rates while in park:
0 across all cylinders
Balance rates in reverse but not moving:
cyl 1: 1.9
cyl 2: 1.2
cyl 3: 1.8
cyl 4. 0.5
cyl 5: -3.1
cyl 6 0.5
cyl 7: 1.5
cyl 8: -2.5
CMDS in miliseconds
inj1: 0.38
inj2: 0.29
inj3: 0.28
inj4: 0.29
inj5: 0.35
inj6: 0.40
inj7: 0.32
Inj8: 0.35
fuel rail pressure desired/actual both at 40 MPa
I assume this means I need new injectors since I dont see any values that are way off? Assuming this to be true, are BOSCH still the best factory replacements?
EDIT: forgot to add the truck is at 190k miles, engine is ~170k miles.. it was replaced when the truck was ~20k miles
I have an 04 silverado 2500 with the lb7. I am getting white smoke at idle.. but even more when in reverse/drive. Reverse is the worst offender in terms of smoke volume.. Drive is hit or miss.. some days its pretty bad (at traffic lights and such) and other days not so bad. In neutral/park its hit or miss.
The smell is pretty distinctly diesel, no fuel in oil and no other symptoms (No power loss, no rough idle, no long cranking to start, etc). I did recently replace the fuel pressure regulator (I forget what its actually called.. replaced it just after Christmas)
I had access to a scanner for about 15 minutes the other day to check for balance rates and such (Are there any decent scanners in the sub $500 category? I got to use a snap on... but I don't have the money to buy one)
Here are a few videos I was able to take to get the data I see people requesting here:
Vid 1:
Vid 2:
Vid 3:
Vid 4:
While checking for these values the truck was 'cold' and only got to run about 10 minutes, not sure how much that hurts/helps the data.
Balance rates while in park:
0 across all cylinders
Balance rates in reverse but not moving:
cyl 1: 1.9
cyl 2: 1.2
cyl 3: 1.8
cyl 4. 0.5
cyl 5: -3.1
cyl 6 0.5
cyl 7: 1.5
cyl 8: -2.5
CMDS in miliseconds
inj1: 0.38
inj2: 0.29
inj3: 0.28
inj4: 0.29
inj5: 0.35
inj6: 0.40
inj7: 0.32
Inj8: 0.35
fuel rail pressure desired/actual both at 40 MPa
I assume this means I need new injectors since I dont see any values that are way off? Assuming this to be true, are BOSCH still the best factory replacements?
EDIT: forgot to add the truck is at 190k miles, engine is ~170k miles.. it was replaced when the truck was ~20k miles
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I am absolutely not an expert. There is guys here who are extremely knowledgeable at this and I am not that guy. But doing my research before i bought injectors (and botched my install) I thought the injectors needed to read around 2. Looks like yours are in a wide range, hence the smoke I assume. But I am not an expert. From my experience dont cheap out do the cups too!! Lol.