My buddy just bought a really clean '06 6.0 with 109,000 on it from a dealer. Truck runs smooth, injectors all sound great on the key-on pre-cycle, cold start is crisp without misfring. Coolant level was at the correct level and was clean. We noticed the turbo was new-ish and had a reman tag on it. I went with him on the test drive, and it all seemed fine. He went wide open during the test drive, but he rolled into it - never just stomped on it.

Now that he picked the truck up and bought it, it's quite clear there is some kind of issue. When you floor it from a stop, it takes a very long time before any kind of boost at all is built and it's quite smokey until it does so. Once it builds boost, it settles right in at ~20-25 PSI or so and pulls hard. It does the same thing when rolling too. If you stomp on it, it will wait a second or two then downshift. At this point the engine will be at ~2,800 RPM but there's still almost no boost. After 2-3 seconds at 2,800 RPM with the truck's speed not increasing at all and a mild black haze coming out the tail pipe, the turbo will spool and the truck will take off.

He used to have an '05 RCLB 6.0 2WD truck that had some limp injectors (had to be fully warmed up before they all came good), and it spooled much much faster and smoked much less than this truck. So we know something's wrong.

I hooked up my laptop with FORScan, and it can command VGT position. If I commanded the VGT to 0% (wide open), the exhaust got slightly louder and deeper, but if I commanded to as high as it could go (85%), the turbo didn't spool up at all. I remember my buddy's '05 would definitely spool the turbo at idle if you commanded max VGT. We also ran the KEOR self-test, and it came back with a turbo underboost code and a low EGR flow code. There is no check engine light, however.

So at this point, I'm thinking the turbo's vanes are partially stuck? It does respond to the position commands, but it doesn't seem to be closing as much as it should. Is that even possible for the vanes to move partially, but not fully? Or do we have a sensor issue? Are there some things I should datalog to verify?

So to reiterate:
- Very laggy and smokey when getting on the throttle. A stock truck should not smoke this much.
- Underboost and low EGR flow code during KEOR test
- Truck has awesome power once the turbo does spool
- Turbo vanes do seem to respond, but does not have the characteristic 6.0 whistling idle when you command the vanes to 100%.

 

well if the turbo is newish


could have uppipe leak


you also should check Turbo control sensors before buying any parts
EBP is that years major control sensor


KOEO check BARO MAP EBP need to be same at this time

 

Would it help to check the MAP sensor tube and fitting?

 

Just as well check IAT #1&2 at KOEO to

 

What numbers am I looking for?

 

Pressure sensor read the same @ KOEO(EBP,MAP,BARO)


Temp senders Read same at 12 hour cold soak @ KOEO


then do pressure sensors again at Idle all 3 (EBP,MAP,BARO)
And AGAIN at 2500 RPM all 3 sensor(EBP,MAP,BARO)


post all values you get under each Operating condition

 

2500 in park/neutral, or 2500 RPM under load?

 

3 hour cold soak KOEO:
Baro:14.5 psi
MAP: 14.5 psi
EBPa:14.5 psi
IAT: 124*f
IAT2: 126*f

KOER Idle
Baro:14.5 psi
MAP:14.5 PSI
ebpa:16.3 psi
IAT: 96*f
IaT2:121*f

KEOR 2500 rpm neutral
Baro: 14.5 psi
MAP: 18.9 psi
EBPA: 29.4 psi
Iat: 92*f
Iat2: 118*f

P2263
P1408
P0299

Thanks

 

P0299 is boost code and is for 4lbs or more and for 5 seconds or more.... stuck vanes.

 

Any more input?

 

Bump, sort of in a rush. Truck is under a 30 day warranty so we want to try and get this issue resolved fast.

 

Your control sensors look good except High EBP @ 2500 RPM in Neutral
High Idle EBP usually comes in a@ 16-20psi your 29psi


The sensors also look good for consistency


I agrre with randy pull turbo for clean and inspection of unison ring


pull egr valve as well inspection or is it deleated???


P1408Exhaust Gas Recirculation Flow Out Of Self Test Range

P0299Turbocharger/Supercharger "A" Underboost ConditionD*

P2263Turbocharger/Supercharger Boost System PerformanceD*

 

Before turbo teardown Really fast I would add to check for any uppipe leak at joints,flex and EGR Cooler connection
be sure it don't leak out

its a new truck this could been someone else problem


con you confirm turbo is OEM and Not powermax

 

The numbers on the tag on the back of the compressor housing indicate its a Cardone re-manufactured turbo for 06/07 MY

 

Could a faulty EBP sensor that reada too high make the PCM open the vanes up too soon? The desired EBP always matches the actual.

When the unison ring on his 05 was stuck. the desired ebp and actual were very different. On this truck they're the same. it makes me think the EBP sensor might be bad.