There is an over boost pressure air line from the turbo (rear of the manifold) to a controller on the firewall and from there is goes to the ALDA device on the injection pump. The idea for this device is that if the turbo produces to much boost the control will limit the amount of fuel. On mine, I used that line to signal a boost gauge I put in the dash. I imagine that once in a while a situation will develop and make to much boost, but I watch mine, and high is 10 PSI, and I like that better then the automatic controller.

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Junqueyardjim
Christianity, if false, is of no importance, and if true, of infinite importance. The only thing it cannot be is moderately important. C.S. Lewis



1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
Mom's car, but I won't let her drive it!