- Joined
- Mar 25, 2010
- Messages
- 15,148
- Reaction score
- 6,325
- Location
- Tonbridge
- Your Mercedes
- W221 S65 AMG - W204 C63 AMG + Various other MB's
- Moderator
- #1
Hi all
My 221 does not make the proper amount of boost through the rev range.
Some thoughts are that there is a boost leak and I am trying to test for this.
I am using a boost tester which is is basically this:
I have 2 of them (one for each turbo) but am only pressurising up through one.
I found a few leaks, but something struck me as odd. All the info says to start with the compressor set to 5psi and then work your way up to full boost pressure. I could not build any pressure in the inlet side of the system until I turned the compressor reg up to 80+ PSI. I Initially think this is due to the restriction that the tyre inflation valve provides.
Even then, I could only build 10Psi in the inlet system. (I had a few leaks but nothing gaping!).
I believe a few one way valves are leaking as well, so have ordered replacements.
Obviously some air will leak past the throttle body, but is this normal? I though this is probably due to a large volume of air being required, but not so sure now.
My 221 does not make the proper amount of boost through the rev range.
Some thoughts are that there is a boost leak and I am trying to test for this.
I am using a boost tester which is is basically this:
I have 2 of them (one for each turbo) but am only pressurising up through one.
I found a few leaks, but something struck me as odd. All the info says to start with the compressor set to 5psi and then work your way up to full boost pressure. I could not build any pressure in the inlet side of the system until I turned the compressor reg up to 80+ PSI. I Initially think this is due to the restriction that the tyre inflation valve provides.
Even then, I could only build 10Psi in the inlet system. (I had a few leaks but nothing gaping!).
I believe a few one way valves are leaking as well, so have ordered replacements.
Obviously some air will leak past the throttle body, but is this normal? I though this is probably due to a large volume of air being required, but not so sure now.