Engine hunting on cold start up

when i start from cold the engine hunts for 50-60 seconds then the tickover is not smooth, its got a purely mechanical c.i.s and as far as can tell the cold start injector and cold start bypass air? valve is working.

When the engine is warm the engine still runs a bit funny

I am certain the timing and spark plugs were changed/checked recently and also for air leaks It has a B200e engine

http://pic7.picturetrail.com/VOL188/...8/23744414.jpg


If you haven`t already done so, clean the inlet tract with carb or brake cleaner, the throttle body is especially important.

Check very carefully for air leaks especially at the big hose shown below.

http://pic7.picturetrail.com/VOL188/...8/24643376.jpg

If no improvement, the thottle stop adjustment should be checked and set as below:-

After cleaning the throttle body slacken the switch screws "B"

http://pic7.picturetrail.com/VOL188/...8/23692958.jpg

Slacken the locknut on the throttle stop screw "A" and back off the ajustment until the plate FULLY closes inside the throttle body.

If it does not close fully you may have to adjust the length of rod "C"

Now screw in the throttle stop screw until it just contacts the lever.

From this point tighten the screw a further 90 to 180 degrees (1/4 to 1/2 turn) and tighten the locknut.

Tighten the screws "B" with the switch positioned so that the switch clicks the moment the throttle starts to open.

Final setting of the idle speed is done with the Knob "D" ONLY.

Colin.

1990 740SE B200E/M47, remote C/Locking.