That's also a good idea to check, cheap and easy. Not a bolt though, it is simply a fitting on the intake manifold that sends pressure to the ALDA via the over-boost protection valve on the firewall near the left front fender.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

First I'd take the over boost protection valve out of the loop. When the valve fails you loose the turbo. Can fail slowly. Also check the connectors for leaks.


Run the vacuum line directly from the manifold to the Alda connector. If the car runs better then leave it that way or replace the over boost protection valve. Like others note: clean the manifold / vacuum line connection out.


If no change then go for the fuel swap out.

__________________

1986 300SDL 440,xxx

Good idea, just note this line is a pressure line, not a vacuum. The pressure line from the intake manifold is provided to the ALDA, which then increases the amount of fuel being injected to match the increased air from the turbo.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

Thanks maxbumpo...pressure line! Good correction.


I think it will also dump boost pressure if the line, connector, or over boost valve is toast.


Definitely not a vacuum line as I misstated.

__________________

1986 300SDL 440,xxx