have a 78 pickup stock 20r. it will start up when cold and idle good for about 15 minutes then start to sputter and die. i can restart but have to give gas to keep it running. carb was just rebuilt and it does misfire a little. Any ideas would be great
same exact truck. same exact problem. i diagnosed mine to be a combination of a vacuum leak and a bad EGR vacume check valve. haha im located in washougal. if you have any questions feel free to shoot me a text 360 936 4829
no problem man. feel free to hit me up whenever. im in Vancouver all the time, i work right off 14, near I5
ok...... still having idle problems..... changed water temp switch checked compression 160 across vacuum is 20lbs steady fuel pressure 4lbs steady the motor ran good with emission components still installed but after i removed the smog pump and unhooked egr it warms up then dies(unless i close the choke) does the carb need to be adjusted for not having the emission stuff? junk the stock carb and buy a weber? any help is very appreciated!!!!!
well...if it was mine, i would junk the carb and get the weber.. i love mine. IF you wanna keep the stocker try to richen up the mixture a lil, if its running with the choke on it sounds like its super lean..
I'd go for a Weber too, although I'd try turning the idle screw out a little and seeing what happens. Might just be lean. If you just rebuilt it it might need some adjustment. Those stock carbs are touchy to vacuum signal too, if you've got any of those hoses wrong it won't run right. That's why I went for a Weber, one hose, done. I'd make sure it's the carb that's the issue first and eliminate any other issues (vacuum leak, timing, etc) before you spend the $$$.
I had more problems with those Aisen carbs. I finally had enough and went to pull a part and found a Weber. It was like night and day. No tinkering or tweaking and no big ugly ass air cleaner.
