Tight turn causes stall

I've been experiencing a puzzling phenomena and think I understand but am not sure. Symptons are that my 300E stalls, particularly if not properly warmed
up, when I move the steering wheel hard left or right. Idle is around 500rpm - not sure why it's low - I'm guessing that the extra load needed by the power steering pump will load the engine, but since it's not part of the servo mechanism (engine computer) to keep idle appropriate, the engine stalls.
am I close? cheers, guenter.
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Guenter Scholz wrote:

Has the OVP Relay ever been changed?
WS
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    No, can't imagine why it would affect engine stalling when cold and turning wheel hard over.
cheers
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Guenter Scholz wrote:

Well, if it's a CIS-E injection system, the CIS part is mainly mechanical and the "E" (electronics) part moderates the idle and cold starts.
The OVP relay supplies power to the electronics. If it's 10 - 15 years old, it's probably dead, that's the simple fix, if not, then it gets more complicated.
Cheers, ws
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The Idle speed air valve should keep a constant idle speed.
So, either this valve does not operate properly, or the mixture at idle is not adjusted properly.
The idle speed air valve is electically controlled by the ECU. If it sticks, it may not regulate the idle speed fast enough. The valve is getting power from the OVP relay (87L), so there is a faint chance, that there is an internal bad connection in the relay.
Also check whether the tubes to the valve are correctly fitted.
The idle speed air valve is behind the fuel distributor (under air filter).
Adjustment of idle mixture is normally not required, and it requires that you have a lambda control tester (on/off ratio). You can however try to adjust it slightly for leaner (CCW) or richer (CW) mixture. The adjustment is accessed throuht a hole in the air filter assembly. There is a small plastic plug, which has to be removed from the adjustment screw, before you can reach it. The adjustment screw is spring loaded, and has to be pushed down to do the adjustment.
But before trying that you should see, if there is a vacuum leak somewhere in the intake manifold system.
/Jens
Guenter Scholz wrote:

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    Jens, thanks to you and WS for your responses. At the risk of demonstrating my complete ignorance, let me ask: is the nomial 700 rpm idle in 'D' or in 'N' or 'P'. As WS suggested I finally did pull the OVP relay but it 'looked' OK for now. Pulled the fuse and it's OK. Turns out that in either 'N' or 'P' my idle indeed is about 700 but drops to 500 when the engine engages. then when I turns the steering hard, quickly, idle drops to about 400 before recovering.... when the engine is cold it does not recover neccessarily and often stalls.
So, is a 500 rpm idle OK when engine is in 'Drive'???
cheers and thanks, guenter
ps I do notice that the idle speed takes a few seconds to stabilize after 'rowing' through the 'gears'.
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The nominal idle is 600-700 rpm. But it should remain constant at different loads. This is what idle speed air valve does (controlled by ECU).
Apparently it does it too slowly. My guess is that it is sticking. Try to take it out and clean it.
Guenter Scholz wrote:

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Aha! Jens, many thanks..... now to find that idle control valve...
cheers, guenter

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The nominal idle is 600-700 rpm. But it should remain constant at different loads. This is what idle speed air valve does (controlled by ECU).
Apparently it does it too slowly. My guess is that it is sticking. Try to take it out and clean it.
Guenter Scholz wrote:

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