Ok I am a bit confused. In the original info on the DMCNEWS site you say between pins 1 and 4 - in here you reference pins 3 and 4. Could you clarify please. ( I actually assume that 1 and 4 is correct based on other op amps ) Incidentally that would be a no I didn't put in the .1 uF caps. I am going to remove the GC again and try to resolder all connections but pulling the boards out far enough has been a real pain. The epoxy or whatever within the strain relief has a death grip. It was quite interesting just replacing the caps and transistors. BTW Is it possible that I have reversed the caps? I know the problem is heat related in some way due to the way and timing of it. It is very consistent. If the car is cool no probs. Once it gets hot it will not go to 3rd, and from 1st to 2nd is sluggish. Solder joints do seem a likely culprit. Hopefully I will get it all fixed this weekend. Would really like to get to the fuel sender. Thanks for all the help. BTW I did disconnect the open throttle micro switch. No change. :( Matthew L. Walker VIN #1219 <snip> >Did you add the .1 microfarad caps across pins 3 and 4 >of the 6-pin >comparator chips? Greatly improved overall stability. Could have cold solder >joint somewhere on the board that opens up with heat. Most likely spot is >where the inter-board jumpers solder on the boards. Been suspicious of <snip>