Trouble Starting & MAF Sensor

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I've got a '78 Westy (2.0 liter FI) that I've had a lot of trouble starting in the cold weather lately. The engine turns over pretty slowly when I try, but I've had the battery charged at Auto Zone a few times and they say it checks out. What's really wierd is that, when I am having difficulty starting it, I can usually disconnect the plug to the air flow sensor, and then it will fire right up. It can't run for very long like this (losing fuel pressure because pump is disconnected?), but as long as I plug the sensor back in I can get it running with this trick on all but the coldest days. What's going on here? Thanks

[NeverHadaBeetle]

If it actually helps to unhook the air flow meter then it's possible your fuel pump is drawing more than its fair share of current. Of course it's also possible your so cold and delirious during the whole episode that your blacking out. Last week I drove my 76 Westy on a couple of mornings when the temps were just below zero and I was so damn cold I could hardly think straight. However, the fuel pump draws power from the solenoid side of the starter so as long as the starter is kicking in then my theory is potentially flawed. But I simply don't think the there is enough other current draws that are triggered by the AFM to really make a difference. Check the wire that runs directly from the starter solenoid over to the fuel pump and make sure it isn't shorting out on the body somewhere. While your under the bus a good ole fashioned cleaning of the starter terminals could only help. And last, but not least (I don't want to rattle anybody's 20W-50 cage), I run 10W-40 oil during the coldest part of winter because the bus starts much easier. By the way I have an oil temp gauge and oil pressure gauge and in temps under 45 degrees the oil temp will barely get to 200 and my oil pressure stays at 35 while cruising with the 10W-40. Good luck.

[keifernet]

try ohming the head temp sensor... see if it checks out. if you do not have it get the Bentley manual. Anyone on here that has to work on or maintain their FI needs that manual!