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JFairman JFairman is offline
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Join Date: Jul 2006
Location: S. Florida
Posts: 7,224
"since it is a cold start issue and I cannot tell the actual pressure until the car if running correct?"

The control pressure on a cold motor will be the same if the engine has just started running or is just sitting there and will stay that way as long as you remove the electric heater element plug from the WUR.
Remove the plug from the cold start aux airslide valve too if you want it to remain in the open coldstart position while the ignition is on and the pumps are running.

That plug is for the heater element on the bimetalic spring inside the WUR so you want it unplugged while the ignition is on and the pumps are running so the WUR stays cold and you can take as much time to adjust cold control pressure as needed.

The bimetailc spring is mounted on the other end of that steel friction fit plug you tap in a tiny bit farther to lower cold control pressure.

It's almost impossible to tap it in and get it in the perfect position especially if it hasn't been adjusted in 20+ years and it's corroded a little. Most likely it will be stuck in place and you'll keeep tapping on it harder and harder until it moves and then it will slide in too far and your cold starts will be a little too rich.
BTDT on old CIS BMW 320i's back in the late eightees many times.

Anyway, you may get lucky and tap it just right and get it really close and alot better than it is now.
You can always take it apart and tap the steel pin back the other way if you go to far or send it to Brian Leask and have him make it fully adjustable.
The 4 flat blade machine screws in the bottom of the WUR holding on the bottom plate can be really tight...

My AFR is around 10.5:1 when I first start my '87 and I can drive off right away after a cold start without any hesitiation or hiccups from the CIS.

The bimetalic spring in the WUR quickly warms up making the control pressure raise quickly, and the idle AFRs are in the mid 14's after a few minutes running.
Old 11-13-2009, 10:42 AM
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