So my 77 FJ40 was in the shop last week and when I picked friday it up it ran fine. Saturday morning she was running a little rough but I had just filled up with a higher octane than usual fuel and figured that was the problem. I haven't tried to drive it since saturday and today when I fired it up it would idle okay but if you pushed on the accelerator at all it would start to sputter and if you didn't release it would die. In checking for a vacuum leak I found that if I pulled the vacuum hose that my finger is pointing at on the carb it runs fine. Any input you give to help direct me in a direction would be great. I a going tomorrow to pick up the FSM from Spectre. Thanks in advance.
Help with vacuum?
- Thread starter Sloan
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That port is connected to the power piston, which in turn engages the power valve. If the power piston does not get sufficient vacuum to keep it retracted, the spring behind it will help it drop, engaging the power valve.
If engaging the power valve off idle appears to correct a malady, you have a different problem.
Getting a FSM can't hurt, but what about asking the shop that just worked on the truck?
Best
Mark A.
If engaging the power valve off idle appears to correct a malady, you have a different problem.
Getting a FSM can't hurt, but what about asking the shop that just worked on the truck?
Best
Mark A.
- Thread starter
- #3
Last night after I got my daughter to bed I got a chance to sit down with my Haynes manual and the truck and realized that I am missing a VSV valve which I found and the hose routing is wrong. I also have a vacuum port on the distributor that was left open. I got popped for my DUI distributor a few months back and went back to the stock one and the aforementioned shop did the swap for me. I love the owner but they seem to have gotten into this pattern of only fixing exactly what you asked them to fix. I don't know if they don't see other problems or what. I just had my FJ60 smogged there and same thing, got it back and the next morning it wouldn't run. BTW, thanks for the help Mark. 
