Turbo boost questions about an 87 5k fwd 5spd.

[Eric_R_Kissell at whirlpool.com]

see:

http://www.sjmautotechnik.com/trouble_shooting/boost.html

What I believe are answers to your questions:

1. the boost gage is accurate but it lags actual boost a little, i.e. it is
slow (overdamped?)

2. this is actual boost from a pressure transducer

3. 1.4 bar is the stock boost limit

4. the link I gave you above covers wastegate testing

Check the lower hose to the wastegate. When these fail/crack/leak you loose
wastegate function and it will overboost, in which case the ecu causes
things to drop out (I think by cutting fuel pump). The boost limit for the
ecu is 1.6 bar I believe. The information on the site above will cover this
and much, much more. Study it well.

HTH,
Eric Kissell
1991 200q 20v Avant, Koni Sports (yellow), 2.4 Bar (MRC), eBay Surprise
1989 200q 10v Avant, Boge Turbogas, 1.8 Bar (qlcc) - FOR SALE
1986 5000cstq Sedan, Bilsteins, 1.8 Bar (SJM)