'81 12A, 5speed, 100% stock. Drove great until I let it sit through the winter. Now, I take it out and she's got no power whatsoever below 5000-5500 rpms, then it takes off like a bat out of hell. Anyone else have this problem, and if so, what did it turn out to be? Otherwise, anyone got any suggestions of what could be wrong or what I should check to figure it out?

Thus far, I've done a fuel volume test, that was fine, I checked the fuel filter by blowing through it, it felt the same as blowing through a brand new filter, so that should be fine.

 

Carbon lock maybe?

 

Sounds like a varnished up carb to me. Causes things to stick open or closed and could be running super rich until high rpms where it has the right amount of fuel. This is just an idea. May want to visually check to see how the carb is spraying fuel.

 

Partially plugged primary jets, takes off when the secondaries open? Either way it sounds like a good carb cleaning is in order.

Isaac

 

Make sure you still have spark on all of the plugs. If that's okay, then pull the jets and see if they're plugged up.

That's what you get for ignoring her for so long...



.

 

Does sound like the primaries are partially plugged and full power isn't achieved till the secondaries kick in.

 

What happens inside the carb when fuel is left to evaporate:

 

Mmmm sorghum.

 

Sorghum is kind of like molasses, only better. Its a food.

 

Cleaned out the jets and also removed the round screens in the fuel rail(?) and replaced them with a paper fuel filter. Still having its stupid problem. Any other ideas?

 

maybe its a spark issue? does the motor sound like its bogging/misfiring all the way till 5000/5500 rpm and then it smooths out? or perhaps its an exhaust leak somewhere?

 

Could be:

1. Old fuel issue. Solution: Drain the gas tank and try again with new stuff.
2. Long shot: Cat converter is shot and creating severe back pressure.

 

clogged

 

I had a simliar issue where I'd only get a kick in the pants when I'd jump atleast half throttle (mech secondaries) turns out the shudder valve was not open/opening (mines actually bracketed open, except them do to intake changes)

 

I think it might be the orange solenoid that controls vacuum advance.. Hopefully going to check it out this weekend, but time is tight. If it were a clogged cat, why would it have plenty of power above 5500rpms? I already changed the old fuel out

 

This doesn't sound like a good idea. What kind of paper filter replaced the screens? Are you talking about the 2 cylidrical screens under the bolts like the one marked with a blue line?



I assume you've removed the plugs and cleaned or replaced them. You might try running a can of Seafoam through the tank. I'd agree that it sounds like the gas in your carb evaporated and left behind something like DD showed you. How did you clean out the jets and are we talking about the primary main jets in the bottom of the float bowl?

 

Those are the screens.. They were crumpled and crudded up, I put a purolator fuel filter in line with the fuel line just before that spot

 

That sounds better. If those screens were crushed whatever gunk was on them is probably clogging the passageways in your carb. Did you use compressed air to blow out the holes after removing the jets? I like to soak the jets in Carb/Parts cleaner for at least 24 hours before blowing everything out with compressed air. You can remove the top of the carb, sponge the gas out of the float bowls with paper towels, and fill them with the same Carb/Parts cleaner to get the passageways clean.

1984 Carb pictures here.
http://intertron.com/ron/carb.html

 

After re-reading your post, I capped off the vacuum feed to the shutter solenoid. The car runs great now. My dad and I worked on this for DAYS, pulled the carb off, cleaned it out, did all sorts of other stuff, and wouldn't have thought of trying this if it weren't for your post. Thank you so much!!!

 

Yeah well would have helped if my original post was in english! lmao

glad to hear you did get the message thou, and not a problem at all thats what places like forums are for.