Loss of power over 35 mph and black out of exhaust on acceleration

[CommoChief]

I’ve got a 2004 with a Detroit engine that suddenly developed a power loss at higher RPM. It starts fine and idles fine, and also runs fine at low speeds. As soon as we try to get above 35 mphnor
So, it looses power.

 

[CommoChief]

I’ve got a 2004 with a Detroit engine that suddenly developed a power loss at higher RPM. It starts fine and idles fine, and also runs fine at low speeds. As soon as we try to get above 35 mph or so, it
looses power.


Changed the fuel filter but no change in power. Anyone have a similar situation and/or any thoughts on what could’ve causing this?

Thanks in advance…..Bill

 

[Thunderbirds]

It just happened that I posted a similar symptom just about 5 minutes ago, haven't read this post, yet.

I had black smoke yesterday, going up a steep hill, I mean steep, at an altitude of over 6,200 ASL. Not necessarily much loss of power, but not a strong pull either. My guess is/was fuel starvation. The over 35mph detail gives me the same gut feeling, more power demand, higher fuel demand.

But I have a similar question for the masses out there: https://www.steelsoldiers.com/threa...-popped-off-while-driving.220455/post-2576640

I will replace the fuel filter anyway, and report back on this thread if it helped.

 

[MarkM]

First stop is the fuel filter and then take it from there.

Mark

 

[Mogman]

The fuel filter should have been one of the very first things changed before parading around the neighborhood showing off your new toy!!
Lose of power and smoke can also be a clogged or partially clogged CAT or intake filter

 

[Thunderbirds]

The fuel filter should have been one of the very first things changed before parading around the neighborhood showing off your new toy!!
Lose of power and smoke can also be a clogged or partially clogged CAT or intake filter

Yes, you are correct. It didn't arrive until last week, and I overlooked it with the other spare and old parts in a pile. I was happy the truck ran. And you'll have to forgive a newb for being excited. Now that I know the difference, this won't happen again.

I just came back from replacing the filter, and the difference is amazing. The truck starts rolling with almost no accelerator input, and sound better, too.

While bleeding, I disconnected the solenoid wire per TM, 54A. While over there, I noticed the other lead, looks like 569B, is just loose on the stud, not much connection. I would imagine the connection would be intermittent at times, or all the time.



Can someone teach me where to find the lead number index, and/or tell me what that one does?

Much appreciated.

@CommoChief, maybe check you fuel solenoid, it could still be starvation that causes your issue.

 

[Mogman]

That is the cold start advance, you should be able to carefully squeeze that barrel connector in the wire fitting to get it tighter, if not you may need to replace the male connector. (Would be female in ANY other world than the military)
Also you are missing the boot on the IP for that wire, not a huge deal just make sure the stud is not loose in the housing allowing water intrusion.

 

[TNDRIVER]

Yes, you are correct. It didn't arrive until last week, and I overlooked it with the other spare and old parts in a pile. I was happy the truck ran. And you'll have to forgive a newb for being excited. Now that I know the difference, this won't happen again.

I just came back from replacing the filter, and the difference is amazing. The truck starts rolling with almost no accelerator input, and sound better, too.

While bleeding, I disconnected the solenoid wire per TM, 54A. While over there, I noticed the other lead, looks like 569B, is just loose on the stud, not much connection. I would imagine the connection would be intermittent at times, or all the time.

View attachment 927821View attachment 927822

Can someone teach me where to find the lead number index, and/or tell me what that one does?

Much appreciated.

@CommoChief, maybe check you fuel solenoid, it could still be starvation that causes your issue.

Post a picture of your old filter......................... diagnostic purposes.

 

[Thunderbirds]

Post a picture of your old filter......................... diagnostic purposes.

Not much to see on the filter, but the bowl was filled with debris in the cup. If that is what was still lose in the bowl, the filter has most likely 10fold in the element...

 

[TNDRIVER]

Not much to see on the filter, but the bowl was filled with debris in the cup. If that is what was still lose in the bowl, the filter has most likely 10fold in the element...

View attachment 927836

Not bad at all. I've seen mine MUCH worse. If you are new to diesels the fuel has some surprises for you, like "stuff" growing in it. Where you live an anti gel additive will be necessary in the winter. The biological stuff can accumulate in the bottom of the filter bowel and cause problems down the road and its difficult to clean on the truck. When you get a chance I would suggest you pull the fuel sender and eyeball the inside of the tank, especially if the new filter clogs quickly. Blow out the air cleaner also, gently. My 2 cents.

 

[Mogman]

Go ahead and add you new info here, even though this thread was somewhat hijacked by the tbird

 

[Coug]

I’ve got a 2004 with a Detroit engine that suddenly developed a power loss at higher RPM. It starts fine and idles fine, and also runs fine at low speeds. As soon as we try to get above 35 mphnor
So, it looses power.

The black smoke out the exhaust to me says unburned fuel.
First things I would check are to look at the air filter restriction gauge on the dash and see if it shows any restriction. Even if it doesn't, I would double check that the air filter isn't filthy dirty, and that the mushroom cap over the air intake tube didn't get shoved down too far. I've heard multiple people that had the cap pressed down, causing the same lack of power and excessive smoke conditions.