cl65 AMG boost questions
MBWorld Fanatic!
Joined: Jun 2009
Posts: 1,559
Likes: 79
2015 Challenger Hellcat, 2023 Ram 3500, 2005 E55 Wagon, 2019 GLC63s
These little turbo's spool really fast and if they hit the wastegate pressure, the wastegates will open right away making the car feel like it has no boost. The bov will not be audible due to it having basically no pressure to dump.
R.K.
R.K.
MBWorld Fanatic!
Joined: Feb 2008
Posts: 1,803
Likes: 12
From: Charleston, SC
GL450
I can see the wastegate pressure line goes into a metal hard line that runs under the coil pack. Where does it connect from there? Does it loop back into the same controller as the diverter line? There are so many pressure/vacuum lines running all over, it is really hard to diagnose. I found the line feeding the diverter had dry rot and was leaking, so I replaced that, but it's hard trying to locate other lines that may have a leak.
MBWorld Fanatic!
Joined: Jun 2009
Posts: 1,559
Likes: 79
2015 Challenger Hellcat, 2023 Ram 3500, 2005 E55 Wagon, 2019 GLC63s
Saintz, if there are lines that are leaking due to being split or dry rott, that can be the issue. You need to find a vacuum line diagram for the car and start looking/replacing those lines.
Goodluck.
R.K.
Goodluck.
R.K.
MBWorld Fanatic!
Joined: Feb 2008
Posts: 1,803
Likes: 12
From: Charleston, SC
GL450
I suspect that when I pinched the one line, it caused the other lines that are T'd in to rupture where they were already a little soft from rot/heat. So there's probably one bad line somewhere. Off to search!
MBWorld Fanatic!
Joined: Jun 2009
Posts: 1,559
Likes: 79
2015 Challenger Hellcat, 2023 Ram 3500, 2005 E55 Wagon, 2019 GLC63s
Senior Member
Joined: Jul 2011
Posts: 386
Likes: 12
Cl65 AMG
I see this an old thread but did you ever find out what was going on ?
Just connected a boost gauge and seems I'm only seeing 15 lbs max. Car runs smooth and has new coils. I haven't done much other than look around the engine bay. The air filter housings and things need to be removed to even get near the turbos etc. The fact I get 15 lbs should give a clue, and I haven't ever herd any kind of blow-off valve sounds at all. I just figured it was designed to be quiet.
Just connected a boost gauge and seems I'm only seeing 15 lbs max. Car runs smooth and has new coils. I haven't done much other than look around the engine bay. The air filter housings and things need to be removed to even get near the turbos etc. The fact I get 15 lbs should give a clue, and I haven't ever herd any kind of blow-off valve sounds at all. I just figured it was designed to be quiet.
Senior Member
Joined: Jul 2011
Posts: 386
Likes: 12
Cl65 AMG
I'll respond to my own question this way.
Since I don't hear any blow-off @ 15 lbs is ether because you just don't here a CL65's pop or its going else where. I don't here any air leaks hissing away under the hood ether. I am leaning to the waist gates, they are something that would effect boost levels with little noise or any service light, well not at 15 psi. Maybe one or both are mis-adjusted, leaking etc. There should be a vacuum signal to tap into and evaluate. I'm guessing they are hard to access ? What about this ?
Since I don't hear any blow-off @ 15 lbs is ether because you just don't here a CL65's pop or its going else where. I don't here any air leaks hissing away under the hood ether. I am leaning to the waist gates, they are something that would effect boost levels with little noise or any service light, well not at 15 psi. Maybe one or both are mis-adjusted, leaking etc. There should be a vacuum signal to tap into and evaluate. I'm guessing they are hard to access ? What about this ?
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
Former Vendor of MBWorld
iTrader: (1)
Joined: May 2008
Posts: 12,139
Likes: 295
From: Houston
2003 W211 E55, 2003 W220 S600
I'll respond to my own question this way.
Since I don't hear any blow-off @ 15 lbs is ether because you just don't here a CL65's pop or its going else where. I don't here any air leaks hissing away under the hood ether. I am leaning to the waist gates, they are something that would effect boost levels with little noise or any service light, well not at 15 psi. Maybe one or both are mis-adjusted, leaking etc. There should be a vacuum signal to tap into and evaluate. I'm guessing they are hard to access ? What about this ?
Since I don't hear any blow-off @ 15 lbs is ether because you just don't here a CL65's pop or its going else where. I don't here any air leaks hissing away under the hood ether. I am leaning to the waist gates, they are something that would effect boost levels with little noise or any service light, well not at 15 psi. Maybe one or both are mis-adjusted, leaking etc. There should be a vacuum signal to tap into and evaluate. I'm guessing they are hard to access ? What about this ?
MBWorld Fanatic!
Joined: Feb 2008
Posts: 1,803
Likes: 12
From: Charleston, SC
GL450
15 psi is a pretty good bit, so you're making some boost. I had what appeared to be none. I never got the issue resolved.
There are two lines that drop by the coil packs down to the turbo, one for waste gate and one for diverter (BOV). You can easily access both lines where they come up on top of the engine (just eyeball them on the turbo connection and trace them back up). May want to remove the airboxes to see better.
There are two lines that drop by the coil packs down to the turbo, one for waste gate and one for diverter (BOV). You can easily access both lines where they come up on top of the engine (just eyeball them on the turbo connection and trace them back up). May want to remove the airboxes to see better.
Thread Starter
Senior Member
Joined: Jul 2011
Posts: 378
Likes: 1
From: LA CA
w215 cl65, W212 E63, R53 Mini Cooper JCW, E92 328I
hello sorry haven't been on in ages. after months and months and more months of diag and thousands of dollars in parts i still haven't found out why it only boosts 15psi, i recently changed my coil rail and i know for a fact there isn't any type of misfire. so i just made my self just believe that's just how they are ........ for the blow off sound.. majority off factory "blow off valves" recirculate which is why they are so quite.. if you figure out the problem please let us all know
thanks vic
thanks vic
Senior Member
Joined: Jul 2011
Posts: 386
Likes: 12
Cl65 AMG
Thank you all for your help especially, "shardul" 
checked the vacuum lines there in good condition.
I did put vacuum to my blow off valves and they seem to work, at least I could here them move around with vacuum applied.
I did put vacuum to my blow off valves and they seem to work, at least I could here them move around with vacuum applied.
I did notice that at the blow off "tee" on the valve cover
i had about 7 inchs of vacuum at idle. That is low( normal engine idle ) but I didn't check directly from the intake vacuum port. Maybe its PWM ?
i had about 7 inchs of vacuum at idle. That is low( normal engine idle ) but I didn't check directly from the intake vacuum port. Maybe its PWM ?
Former Vendor of MBWorld
iTrader: (1)
Joined: May 2008
Posts: 12,139
Likes: 295
From: Houston
2003 W211 E55, 2003 W220 S600
Thank you all for your help especially, "shardul"
checked the vacuum lines there in good condition.
I did put vacuum to my blow off valves and they seem to work, at least I could here them move around with vacuum applied.
I did put vacuum to my blow off valves and they seem to work, at least I could here them move around with vacuum applied.
I did notice that at the blow off "tee" on the valve cover
i had about 7 inchs of vacuum at idle. That is low( normal engine idle ) but I didn't check directly from the intake vacuum port. Maybe its PWM ?
i had about 7 inchs of vacuum at idle. That is low( normal engine idle ) but I didn't check directly from the intake vacuum port. Maybe its PWM ?
Senior Member
Joined: Jul 2011
Posts: 386
Likes: 12
Cl65 AMG
Yes, the vacuum lines in question were fine. I still need to look further in the direction of the vacuum source which would be the intake port at the back of the engine. I did get vacuum but only 7 inches so I would like to make sure its not leaking somewhere behind the valve cover. What engine makes 7 inch's of vacuum at idle ? None except one with a big cam. The 65 should make more than that. Unless its PWM through the control valve. I think I will apply 7 inches of vacuum to the blow off and see if it operates, I can here it operate using a vacuum pump but I can't here it move with the engine running. My guess is the valve will work fine with the above low vacuum number. I just have to look around a bit more.
MBWorld Fanatic!
Joined: Dec 2004
Posts: 4,268
Likes: 253
Former Vendor of MBWorld
iTrader: (1)
Joined: May 2008
Posts: 12,139
Likes: 295
From: Houston
2003 W211 E55, 2003 W220 S600
Yes, the vacuum lines in question were fine. I still need to look further in the direction of the vacuum source which would be the intake port at the back of the engine. I did get vacuum but only 7 inches so I would like to make sure its not leaking somewhere behind the valve cover. What engine makes 7 inch's of vacuum at idle ? None except one with a big cam. The 65 should make more than that. Unless its PWM through the control valve. I think I will apply 7 inches of vacuum to the blow off and see if it operates, I can here it operate using a vacuum pump but I can't here it move with the engine running. My guess is the valve will work fine with the above low vacuum number. I just have to look around a bit more.
MBWorld Fanatic!
Joined: Jul 2010
Posts: 1,477
Likes: 1
From: Colorado
07' SL65, 04' E55, 03' Evo8, 08' GSXR, DSM's...
I think i will hook up a boost guage just to see where i am at too although i am pretty confident my car runs just fine. I haven't driven any other 65 series cars to compare but am curious now as to where i am at. Will hopefully report back if the weather clears up this weekend and i take the car out.
Shardul, what was your issue with the low boost that you were having?
Aaron
Shardul, what was your issue with the low boost that you were having?
Aaron
Former Vendor of MBWorld
iTrader: (1)
Joined: May 2008
Posts: 12,139
Likes: 295
From: Houston
2003 W211 E55, 2003 W220 S600
I think i will hook up a boost guage just to see where i am at too although i am pretty confident my car runs just fine. I haven't driven any other 65 series cars to compare but am curious now as to where i am at. Will hopefully report back if the weather clears up this weekend and i take the car out.
Shardul, what was your issue with the low boost that you were having?
Aaron
Shardul, what was your issue with the low boost that you were having?
Aaron
Senior Member
Joined: Jul 2011
Posts: 386
Likes: 12
Cl65 AMG
That is what I would expect to see from a straight connection to the intake. I did my test from the blow off valve area. I'll check now that the engine is cold and post the numbers. BTW the engine runs very smooth as it should, surely not like one with a gapping huge ugly (LOL) vacuum leak.
Senior Member
Joined: Jul 2011
Posts: 386
Likes: 12
Cl65 AMG
Picture of boost vacuum lines on valve cover ?
It seems I have a single vacuum line, small plastic one on the passenger valve cover that is not connected to anything. It does have vacuum there. Both the solenoids there have all the lines connected. One has a vent and one does not.
A picture would help me out. Having trouble downloading my pictures from my phone to my computer. Seems I have lost all my drivers, to my printer, camera and phone. Not nice !
A picture would help me out. Having trouble downloading my pictures from my phone to my computer. Seems I have lost all my drivers, to my printer, camera and phone. Not nice !
Senior Member
Joined: Jul 2011
Posts: 386
Likes: 12
Cl65 AMG
Just to add I did remove the driver side h/e and found one solenoid. There were three ports, only two were being used ? The one pointing to the rear of the car had nothing connected. I connected them, the one from the passenger side to the driver side solenoid. the with no change/ really less boost but its a 95 degree day. Saw only 7 pounds of boost with a slight spike at throttle close. I need to drive it with my scanner to look at air temps. I have to check my laptop, I had a spare engine & transmission at one time and did snap a ton of shots.
IF I find some I will post them for you all
IF I find some I will post them for you all
Former Vendor of MBWorld
iTrader: (1)
Joined: May 2008
Posts: 12,139
Likes: 295
From: Houston
2003 W211 E55, 2003 W220 S600
the one under the driver side is the boost control valve, one of the ports have to be open to the atmosphere.
look at these pics and you will see how all the lines are supposed to run. call me you have my number if you have more questions
look at these pics and you will see how all the lines are supposed to run. call me you have my number if you have more questions
