Possible Turbo problems. ATS 093

[tbirdfiend281]

Ok, the truck is as follows, ats 093 kit that I put on, bought used locally, complete factory installed kit, 2.5" banks downpipe and a 2.5" straightpipe. 84 6.9 c6 4.10 truck, uses a little oil, no coolant, and generally runs well, fuel settings are stock as stock can be pump and injectors are in good working order to the point the truck has a light has a light haze near WOT at highway speed but that is really the only time you see anything out of the tailpipe at all.

Well friday my buddy and I where bored and began to install a boost gauge on the truck. I had the bright idea to tap the wastegate line for the boost signal. So I unhook the wastegaste line, run it away from the actuator and directly into the boost gauge, just to get a check and see if the signal is good and everything is fine. It does get a boost signal, but I am only seeing 6psi on the gauge. I figured with the wastegate actuator pressure line unhooked the wastegate shouldnt really actuate at all, and the boost would be in the 7-8psi range. Well after the quick run to get drinks, I try and move the wastegate and it seems to be locked up, would not move either direction. I think there may be an issue in there, I have to unhook the rod to determine if it is in the exhaust housing or in the wastegate actuator, but wanted to touch base here first to get all the correct information I may need before I go and do this, because if its an issue in the exhaust housing, I am going to have to pull the turbo off and work some magic.

So that being said, what do you guys think may be going on? Did these 093 kits have issues with the wastegates often? Is the wastegate super difficult to move with a pry bar or is there actually a problem?

FYI to keep this from being a redundant forum thread, I have a lot of experience working with turbos and diesels.

thanks people.

 

[icanfixall]

Well with the actuator rod disconnected from the gate it will move easily open or closed. But you posted yours wont move now does the boost increase when the pressure line is removed from the can. In that can is a spring. The spring tension keeps pressure on the gate to keep it closed. Then as boost pressure increases that boost pressure equals out the spring pressure and opens the gate so no more boost pressure can be made. When the gate opens it diverts hot exhaust gas around the turbo hot wheel. That acts to lesson the pressure on the spinning of the turbo shaft and fans. The pressure and heat work together to spin the turbo faster which makes more boost. If this used turbo came from an engine that had a coolant leak into the exhaust it very well could have rusted up the wastegate shaft bushing. Do this. Remove the plunger rod from the gate lever. Now tap the lever ever so softly with a hammer. See if it frees up. Probably should use some Aerokroil on it before you try this of some PB Blaster. Both penetrants work great with heat so apply it when the turbo is hot. Allow it to naturally cool down. Then do it again. The penetrant will work into the bushing better than way.

 

[fx4wannabe]

I'm curious to see if this is your problem. I am having a similar problem. I can hear my turbo spooling but I can't get more than 5 psi and if I keep it under 1800 rpm I can keep the boost at 0. I am reading off the intake hat. I haven't dug into the waste gate yet as I had an exhaust leak which I fixed but still have low boost.

 

[tbirdfiend281]

So it is not a turbo problem. Yesterday I was playing around with the truck and noticed a little oil seemed to have pushed out of the intake hat. Come to find out, it was cocked slightly, so I refitted the intake hat, and now my truck sees about 8-10lbs WOT. It gained a lot of power vs the 5 I was seeing before and there is less turbo sound, witch is a little disappointing, but power makes up for it.

 

[icanfixall]

Its really surprising how small of a intake or exhaust leak will cause a big boost loss. check closely for any intake leak or exhaust leak.

 

[sassyrel]

So it is not a turbo problem. Yesterday I was playing around with the truck and noticed a little oil seemed to have pushed out of the intake hat. Come to find out, it was cocked slightly, so I refitted the intake hat, and now my truck sees about 8-10lbs WOT. It gained a lot of power vs the 5 I was seeing before and there is less turbo sound, witch is a little disappointing, but power makes up for it.

in your first post,,you said uses a little oil....... did it do this,,before the turbo install???? if not,,you have the sealing rings getting bad in the turbo...esp since you said some oil was coming out of the intake hat......

 

[79jasper]

It seems oil out the intake hat is the norm for a boost leak there.
Sometimes you can just Rev it by hand when looking at the gasket and see the leak. May need soapy water.

Sent from my SM-T537R4 using Tapatalk

 

[tbirdfiend281]

The slight oil usage is not related to the turbo, it is about the same as before. It doesn't even go out of range over a 5k oil change so I am not worried about it. It blew my block heater out of the block last night though, so I have to address that this weekend.