1151 Power Loss

[jake20]

Heya all, hope everyone’s had a good Memorial Day weekend.

I’m coming across an odd issue in an 1151 where after it’s warmed up, it just loses the will to move at any sort of pace.

From cold I wasn’t able to get it over 50mph, then once fully warm it didn’t want to accelerate at all past 20.

Fully stepping on the throttle once warm would cause a metric ton of black smoke from the exhaust, same while revving

I tested all 4 gears on the shifter manually and it was definitely rowing through them smoothly.

I’m thinking the following:

Transmission may have an issue and has a bunch of resistance once warmed up, thus the black smoke when stepping on the pedal. Tons of fuel getting thrown at it but not enough rpms. This wouldn’t explain the huge plume of smoke when neutral revving though

Injection pump related issue with either adjustment or timing?

Will post as I discover more.

 

[jake20]

For what it’s worth, I changed the lift pump and filter a few months ago but it’s only had a few miles done on it.

It’s been sitting most of the time. I just verified the fuel flow from the lift pump while cranking, fills up a cup pretty quick, no evidence of dirt / debris from the filter drain either.

 

[jake20]

Alright while this certainly looks cool, it ain’t right

I tested it a bit more just now and it seems to be getting worse. Is it possible that the fuel adjustment inside the IP might’ve come loose and is increasing fuel by itself?

Given the ridiculous smoke levels and full throttle only going to 2900rpm in neutral, I think the transmission can be ruled out?

 

[jake20]

Another video:

Engine peaked at 2250RPM at full throttle in 1st gear

 

[jake20]

Further research and discussion seems to point to this being turbo related.

Friend brought up the idea of the wastegate possibly being stuck. I was able to move it by hand with the truck off though. Going to try moving it around with the truck running tomorrow and seeing if the smoke level changes.

I’ve seen a few others in some other threads also mention that an inop turbo will cause plumes of black smoke and no power. Just like my issue. This theory makes the most sense so far, tons of fuel but not enough air.

What’s interesting is that it got progressively worse today. When I first took it for a drive, I was able to peak around 2900rpm and get up to 50mph. Then a few minutes later it would barely move at 20mph and puff smoke. I’m curious as to what kind of failure mode this could be.

Need to test the turbo somehow besides just moving the wastegate around.

 

[Mogman]

It sounds like you may have a bad injector, try breaking each line loose at idle and see in they all create the same change in idle sound/rpm, in the first video I can hear the turbo spool up so that would not be my first assumption.
How about the intake filter?

 

[jake20]

It sounds like you may have a bad injector, try breaking each line loose at idle and see in they all create the same change in idle sound/rpm, in the first video I can hear the turbo spool up so that would not be my first assumption.
How about the intake filter?

That spooling whine was actually the inertia of the 200A alternator spooling down, my non turbo does the same thing when revved high in neutral and released.

I actually ran it without the filter in the first video, intake was wide open with no obstructions.

I can give it a shot though to rule them out, though it does run very smooth aside from the lack of power. When I was doing that on my 1043 a while back, it sounded kind of like an old tractor as I cracked each injector loose lol.

 

[Retiredwarhorses]

Your catalytic converter is clogged or the turbo isn’t spooling up…the Catalytic converter issue is most common.
disconnect the down pipe at the turbo exhaust outlet and loosen at the muffler to move out out of the way.

 

[jake20]

Your catalytic converter is clogged or the turbo isn’t spooling up…the Catalytic converter issue is most common.
disconnect the down pipe at the turbo exhaust outlet and loosen at the muffler to move out out of the way.

Temporarily removing it from the exhaust system in that case should let me test and rule it out then I suppose?

 

[Retiredwarhorses]

Temporarily removing it from the exhaust system in that case should let me test and rule it out then I suppose?

Huh?

 

[jake20]

Oh just saw the edited message, alright yea that makes sense and sounds simpler than removing the converter off the bat. Will give it a go.

 

[rcamacho]

+1 who has experienced a plugged cat ‍ on the 11xx turbo series.
Prior triage guidance is correct


Sent from my iPhone using Tapatalk

 

[jake20]

I suppose it’s also possible a blown/leaky intake o-ring on the turbo could be leaking my boost?

About to do some testing and see how things line up.

 

[jake20]

Alright it looks like we are possibly leaning towards a plugged up cat. While driving under moderate load, I get smoke coming from the exhaust side of the turbo area and down pipe as if excess exhaust pressure is trying to escape but can’t. Turbo also got to temp very quick.

Moving the wastegate around didn’t do much and I felt no air pressure leaking from around the intake o-ring area.

 

[jake20]

Holy sh$!

It’s a completely different truck now

I slid the cat back away from the down pipe and this thing hauls now. The turbo whistles like a beast and the temps stay lower, I got it up to 65mph in no time. No more black smoke plumes either, nice clean exhaust

Good stuff guys thank you all!

 

[Autonomy_Lost]

Nice!

How does this happen? Are there a ton of miles on it? Is it a result of some "event" or does it just happen slowly over time?

 

[jake20]

So I guess to add to the record here, this truck’s odo has 12k on it right now. Obviously can’t attest to the accuracy of that though.

Could it possibly be from fording salty/nasty water and it finding a way in there to sit?

 

[87cr250r]

Excess idling will plug a cat. The turbo outlet o-ring does age over time but it requires a lot of hours to do unless maybe the truck was parked in the desert. I put a silicone o-ring on mine. -408 was the size. A dab of PTFE grease makes it assemble and disassemble easily.

 

[Retiredwarhorses]

Holy sh$!

It’s a completely different truck now

I slid the cat back away from the down pipe and this thing hauls now. The turbo whistles like a beast and the temps stay lower, I got it up to 65mph in no time. No more black smoke plumes either, nice clean exhaust

Good stuff guys thank you all!

your welcome

 

[HoveringHMMWV]

Could this also be why these trucks blow soot out of the fording exhaust?