Turbo issue??
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Joined: May 2015
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Turbo issue??
So I am not sure exactly what is going on with my truck. It is a 2004 F250 has a 6.0 L.
Sometimes when I take off from a stop the truck has no power and blows some blacks home. Then the turbo kicks in and all is fine. It comes and goes when it pleases no matter the temperature. What started happening is when I drive it a steady pace on the highway sometimes the turbo gets quieter and louder and quieter and louder sometimes when it gets quieter I see a little bit of black coming out of the tailpipe. Sometimes it doesn't do it at all.
Also sometimes when I let off the gas the truck sounds like it's trying to laugh at me like a wastegate is fluttering.
Sometimes when I take off from a stop the truck has no power and blows some blacks home. Then the turbo kicks in and all is fine. It comes and goes when it pleases no matter the temperature. What started happening is when I drive it a steady pace on the highway sometimes the turbo gets quieter and louder and quieter and louder sometimes when it gets quieter I see a little bit of black coming out of the tailpipe. Sometimes it doesn't do it at all.
Also sometimes when I let off the gas the truck sounds like it's trying to laugh at me like a wastegate is fluttering.
Postmaster
Joined: Sep 2010
Posts: 3,472
Likes: 2
From: Southern Cal
You need to pull any codes off your obd connection. You very well might have a stuck unison ring in an overboost position to create that waste gate sound, even though you don't have one.
Live data help even more, vgt's command. Also pull your baro, egt, and map #'s at key on, engine off.
You should see similar readings although, don't be fooled by psi vs hg's of mercury when comparing.
Live data help even more, vgt's command. Also pull your baro, egt, and map #'s at key on, engine off.
You should see similar readings although, don't be fooled by psi vs hg's of mercury when comparing.
Logistics Pro
Joined: Jan 2010
Posts: 3,554
Likes: 6
From: Mesick
Ok, we're going to need more info here. What did you try to pull codes with? Are you monitoring anything? With what device? What values are you seeing?
Logistics Pro
Joined: Jan 2010
Posts: 3,554
Likes: 6
From: Mesick
There's several different options depending on what your intentions are with the truck or your budget.
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Laughing Gas
Joined: Dec 2005
Posts: 972
Likes: 224
From: Linden, Ca.
I'm having a similar issue. Started several days ago with no to very little boost during acceleration. No black smoke or unusual exhaust emissions. Atles 40 tune in FICM. The problem happened several times. Fired up OBD Link and had a look. When the problem would arise she was only generating 7-9 psi boost under full throttle.
Ran some numbers today.
Cold VGT at 75% at idle with .6-.8psi boost and cruise 54% with 5-7psi boost.
Hot VGT at 63-68% at idle and cruise at 45%.
Operating temp normal acceleration from stop VGT 38-41%.
Operating temp full throttle from stop VGT 35-55% and MAF at 35.7lb/min
Operating temp steady 55 MPH VGT 45-50% and MAF at 10/7lb/min.
NO TROUBLE CODES.
132K+ miles.
Turbo was removed and cleaned about 50k ago.
So the only thing is, is intermittent low boost with PSI below 9 when it does happen and engine will gain full RPM's but very light acceleration at the same time. Almost like the transmission is slipping, but it is not. Recently did dummy plugs and stand pipes.
I suspect a sticking unison ring. What is the consensus guys? Bruce
Ran some numbers today.
Cold VGT at 75% at idle with .6-.8psi boost and cruise 54% with 5-7psi boost.
Hot VGT at 63-68% at idle and cruise at 45%.
Operating temp normal acceleration from stop VGT 38-41%.
Operating temp full throttle from stop VGT 35-55% and MAF at 35.7lb/min
Operating temp steady 55 MPH VGT 45-50% and MAF at 10/7lb/min.
NO TROUBLE CODES.
132K+ miles.
Turbo was removed and cleaned about 50k ago.
So the only thing is, is intermittent low boost with PSI below 9 when it does happen and engine will gain full RPM's but very light acceleration at the same time. Almost like the transmission is slipping, but it is not. Recently did dummy plugs and stand pipes.
I suspect a sticking unison ring. What is the consensus guys? Bruce
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Postmaster
Joined: Sep 2010
Posts: 3,472
Likes: 2
From: Southern Cal
Check your MAP hose that runs down to your pass side valve cover. They are known to split, crack, and create havoc when they get rotten from high temps right at the connection.
Easy thing to check and replace. I don't think it sounds like the unison ring based on your vgt command numbers.
Easy thing to check and replace. I don't think it sounds like the unison ring based on your vgt command numbers.
Laughing Gas
Joined: Dec 2005
Posts: 972
Likes: 224
From: Linden, Ca.
Well, I pulled my MAP sensor and hose off today. The exterior of the hose looked fine. I tried to vacuum test it and the assembly would not hold a vacuum. Changed out the hose and vacuum tested again. This time it DID hold a vacuum. I re-installed the MAP and hose assembly. Did not take it for a test drive yet today. Will see how she runs this week.
Here is a pic of the hose. The end view was at the intake manifold side. You can see some cracks along the interior section of the hose. The exterior still looks fine. It was too short to cut and reuse.
Thanks for the tip Bob. B.
Here is a pic of the hose. The end view was at the intake manifold side. You can see some cracks along the interior section of the hose. The exterior still looks fine. It was too short to cut and reuse.
Thanks for the tip Bob. B.
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