Help with another squealing noise from my D12...

Had the same problem. It's the egr gaskets. The EPG closes on a cold start and restricts exhaust flow, thus producing more back pressure which results in the whistle because your egr gaskets are no longer sealing correctly. The whistle goes away because the EPG opens up once the engine reaches a certain temp. It also maybe there at idle as the EPG closes again to force more egr. As soon as you press the throttle EPG opens and whistle goes away.

you are also most likely getting exhaust smell in the cab at idle.

get your egr clamps and gaskets replaced.

 

Try tightening the clamps, they may have just come loose. I'm taking my volvo into the dealership today for the exact same problem. They replaced the clamps and gaskets 20k ago and they are leaking already. They are talking about replacing the exhaust manifold as they are saying the surface maybe pitted too much to get a good seal. Me thinks differently on that one. Funny how the original egr valve latest 600k+ with no leaks and now this new one will not seal. The replacement valves are all rebuilt ones with the original intake and outtake manifolds. Personally I think that the mating surfaces on the egr valve has been badly machined or is just too pitted and will not allow a good seal. Either way they going to have to put a new egr valve under warranty on first to see if that cures the problem before I cough up for a whole new exhaust manifold plus associated gaskets and labor.

 

Well you have to clean the paint off the egr when assembled and clean the manifold with a cookie or brush then you have to make sure it's sitting properly. Also I would definately suggest using new clamps and tight them down good not only by torque.

 

I just replaced my turbo and had the same squeal when I realized I hadn't tightened the egr clamps.....I has replaced the gaskets and cleaned the surfaces with a wire wheel. I tightened the clamps with a battery impact using short trigger pulls. Now no leak. The new problem is making a s-pipe that will mate directly to the turbo. Epg is going bye bye!!

 

Y would you not want the EPg if you take it off then you're engine brake is not going to work properly as well you're only going to have one position being that the EPg is the first position in the engine brake plus they don't go bad that often that's y I'm wondering y u want to take it off. You can just plug the air line going to it and its just not going to work you don't have to make the s pipe

 

If I just plug the air line like you suggest then I still will only have one position for the jake. So, I removed it today and have noticed immediately that the motor is breathing better and the turbo spools much faster. If you look inside you'll see that there is only about a 2 inch gap for the exhaust to get out even when the epg is fully open. By removing that obstacle I am hoping for mpg gains. I will post my results after a few fill ups (good or bad). If my theory is incorrect then I will put it back to factory spec.

 

I know how much gap it has vary well you might be on to something I don't know if its going to make a lot of difference but please let me know how it turns out

 

So what was the outcome?