" How would one diagnose a failing turbocharger?" Measure boost pressure under load. Tee into that same boost pressure line to the ALDA and connect to a cheap mechanical pressure gauge via rubber hose. If you tape the gauge to the windshield, you can test drive and watch the meter to see what happens under load.
Having said that, if the ALDA doesn't see the boost signal, the IP won't add additional fuel and the resulting exhaust isn't hot enough to really spin the turbo. Likewise, a fuel restriction will produce same symptoms. So low boost pressure at the ALDA isn't conclusive. Someone already mentioned the need to unsure the boost pressure tap on the intake manifold isn't clogged (very common but also very easy to check/clean) _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
