My 760 turbo has been developing an annoying habit of suddenly dropping the idle speed from the normal 750 rpm to 450-500 rpm when stopped. This is frequently accompanied by no throttle response (none, nada, zilch etc) for an agonizing 5-10 seconds when trying to resume speed. After the 5-10 seconds a smidge of hesitation is felt and then normal power returns. Usually, once the low idle problem starts it will continue until the ignition is turned off. The no throttle response problem, however, will only occur once or twice during this period. The no throttle respone problem hasn't occurred unless accompanied by the low idle. After the car gets rolling, power and response are normal. Point me in the right direction and I'll report the results. Thanks!!

Oh man this was soooo agonizing when it happened to me. OK, with my car, there's a braided looking wire that serves as a ground that comes from somewhere in the back of the engine by the distributor and goes towards the firewall. This was loose and it would intermittently ground itself out, cut power in half and kill the idle. I'm not sure what this wire is for, but the tech sautered it back to where it was supposed to be and I was on my way.

Hope that helped

Ryan

Ryan, I checked that braided wire (actually 2 in my case, both from the firewall, one to each side of the rear of the engine valve cover) and they were in good shape. Thanks!!

Vacuum leak or fuel pressure regulator malfunction?

Well, fault code 1-2-1 has been set on the car. This code points to the AMM and the manual suggests some tests on section 2 (23) of the green book. The AMM passes at least 2 of the 3 specified tests. The 3rd test checks for burn-off after the engine is shut off and specifies that "...the needle on the voltmeter should oscillate for around 1 second...". My digital meter blips from 0.0 to about 3. volts and back again once very quickly. If this test is OK, then I could really use some additional direction. Thanks, guys!!