90 Cadillac DeVille with 4.5 L engine has started to stall intermittently while driving. Will happen at any time. Has happened while driving on the highway, or on entrance ramp to a highway, accelerating up a slight grade, turning a corner, etc. Occurred about 4 times over 15 miles. Gas tank was down to about 4 gal. level. Restarts immediately. I have not seen any check engine light come on with this problem, but I have occasionally seen code E30 (ISC rpm out of range). Any suggestions about possible causes or ways to analyze.

 

Do a search on this forum for "crank sensor". If I recall, the crankshaft position sensor will fail at times and happens so quickly the ECM cannt record it. Just a guess without a code? ISC out of range could be because the car stalls and the throttle is partially open. ISC only works when your foot is off the throttle.

 

Being condition only happens when 1/4 tank or less. Problem could be with sender or fuel pump pick up/strainer.

 

I agree. Rule out the fuel level by keeping it above a quarter tank for a week and report back.