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Low power/Lots of black smoke!!!!!!!!!!

dieselkidd04

Member
Messages
71
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9
Location
elburn illinois 60119
well my dads 04 lb7 started running like dog shit so i took it for a spin, when you get on the throttle it has little to no power and just pores out black smoke, changed the fuel filter just to keep it simple,no luck plugged it into my code reader, had 6 codes but i think some are old ( at least the trans codes)
1-p0101 MAF sensor
2-p0236- turbo boost sensor A circuit malfunction
3-p0380 glow plug heater circuit malfunction
4-p0404 egr circuit range performance
5-p0802 tcm mil range circuit
6-u2106 lost communication with tcm
Now i was thinking to start with the boost sensor, seems that might cause the most power issues but im not sure , hopefully someone has seen this before.
 
Check all harness connectors, make sure they are pushed in all the way.
 
Stock air filter? If it's an oiled one, clean the MAF sensor with some Brakleen.
I didn't think LB7s had egr.
Didn't you or your brother put a programmer on it? If so, change the tune back to stock.

BTW guys, this is my Brother-in-law's truck.

On edit: Jimmy (dieselkidd) is at work and I just talked to the B-I-L to give him these ideas. He's running a K&N and has cleaned the MAF with no luck. He's gonna' check out the other things.
Other ideas welcome.
 
Last edited:
Don't use brakleen on the MAF. Use MAF specific cleaner, or rubbing alcohol and a q-tip and be VERY careful.

You ran the codes, can you scan the parameters?
 
Check over by the power steering pump and see if the power steering hose has rubbed a hole in the metal intercooler tube. The ECM uses the MAF to determine max fueling, so if there is a leak in the intercooler plumbing it will give max fuel even though the engine isn't getting it(it only watches airflow and not boost). The P0101 is a good indicator yuou have a boost leak though. And some LB7's do have EGR on them, CALI and New England emissions trucks came with it.
 
The circuit malfunction describes just that. You have a short, intermittent connection, open wire, or bad sensor that is pulling all the sensors that gave you the code down. I have seen wiring harnesses get melted on the hot side plumbing of the CAC tubes.

However a sticking EGR will pour out the black due to no "burnable" air. Does it really have an EGR? If so back pressure will force air through it and the MAF will see too little air and trip.

Remove the MAP sensor and see if it is plugged solid with soot. (Yes, MAP not MAF.) Could also be known as a turbo boost sensor.
 
well just got back from work thanks for all the replies, the truck had a edge attitude programmer on it but it was just recently taken off to upgrade to efi live but that hasnt happened yet, gunna check the intercooler tubes tomorrow for boost leaks and ill check the map sensor, ill keep the post updated.
 
Stock air filter? If it's an oiled one, clean the MAF sensor with some Brakleen.
I didn't think LB7s had egr.
Didn't you or your brother put a programmer on it? If so, change the tune back to stock.

BTW guys, this is my Brother-in-law's truck.

On edit: Jimmy (dieselkidd) is at work and I just talked to the B-I-L to give him these ideas. He's running a K&N and has cleaned the MAF with no luck. He's gonna' check out the other things.
Other ideas welcome.

Mike always use electrical parts cleaner. Not brake cleaner.
 
Edge programmer?

Stop.
:mad2:

Block or disable (in the tune) the EGR.

Continue on....

I offered to burn a friends 2007.5 OBS truck for free after towing with that belching black smoker with no low end. It would not get out of it's own way from a stop then it would run like crazy. Low RPM it would smoke with no power in high gear. EGR would open and choke the engine. After EGR was blocked with a plate you could hardly keep traction on take off.

He was very surprised that the truck came alive after the blocker plate was installed. I gave him the plate for free just because it ran so bad without it while tuned with the edge.
 
If its throwing EGR codes then yes it has EGR. If my truck was throwing supercharger codes I would assume it has a supercharger. Just saying.

Many Cali Emissions trucks out there, not too many make it to illinois but it happens.

CRC makes MAF cleaner, buy a can of it just to have it, comes in handy more than you think.

x2 on checking the boost tube down by the powersteering lines. Both of our farms LB7s had the tubes wear through there. Its cheapest to just replace with a banks tube unless you find a used stock tube cheap, call Jim @UDP.

Mix yourself up a bottle of soap water, and keep it in your shop. Very handy stuff. Spray all of the intercooler boots and then have somebody rev the truck up to create a bit of boost, it doesnt take much pressure to shop leaks. look for bubbles.

If the CAC system checks out then I would look into the EGR issue closer. Or just delete the damn thing.
 
Well got home from work today,opened a beer and took a look at my dads truck, no signs of boost leakage used soapy water on all intercooler tubes and hoses, there was some rubbing on the pipe near the powersteering pump but nothing causing a leak, my dad checked the maf sensor and cleaned it, I removed the intake and air filter and actually found some peices of corn that the mice must have hid near the turbine wheel (not sure how it didnt chop it up but whatever) not my main concern right now,checked all of the hoses and pipes and tubes like I said and im not to sure where to go from here I dont want to tear into this engine if i dont have to )wish i was going to dmax school next week instead of cat engine school but oh well , also could anyone give me the specs and location on the map sensor for a lb7 that would be great.
 
MAP sensor is next to the intake grid heater. Its in the intake manifold y-bridge, the bast piece where the passenger side CAC tube connects to.
 
alright well,tried to clean the peices of corn out of the turbo, couldnt get them out, also i couldnt get the turbine wheel to spin with a long screwdriver, had to remove everything around turbo, intercooler tubes,intake horn, wastegate and brackett, unbolted front turbo horn(which was fun and so accessible) ha ya removed the front section of the turbo, cleaned all the foreign objects out, well see how i goes tomorrow.
 
How did mice get in by the turbo? I'd be making sure there isn't a nest somewhere else too, like in the air box, and be giving the entire harness a thorough looking over.
 
Get rid of those damn useless dogs over there and get some cats.:hihi:
Either that or train the dogs to hunt mice...;)
 
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