'68 289 2V

The car cranks and idles great.......except.......it's idling at 1800 rpm's and won't idle down........also as soon as I give it a footfull of throttle, it goes dead.........I can "blip" the throttle, but anything past 3/4 causes it to go dead when it winds back down.

I have played with the choke incessantly........also, the fast idle screw on the throttle linkage is backed all the way out.

I am puzzled.

The car ran fine until it stranded me about a month ago.......vapor locked.....haven't been able to drive it since that happened.......it does not want to run when you give it gas and idles in the stratosphere. I took the air horn off last night and cleaned the float bowl out.....it is getting PLENTY of fuel.

I have a Petronix ignition on order and it should be here next week.

Any ideas? I used brake cleaner to look for vacuum leaks and could find nothing wrong.

In the not too distant future I plan on going to a 4bbl but for now I really need to get this thing figured out so it will run until then.

This may be something simple that I'm missing.....actually, I HOPE that is the case.

Any and all help or suggestions will be greatly appreciated.

 

Insert crickets chirping....................


NOBODY has advice?

What did I say wrong in my post?


I actually managed to drive the car to the end of my subdivision and back yesterday.......it only went dead when I pulled back into the garage.

I am rapidly running out of hair to pull out.

 

well no, just not easy to troubleshoot. with the choke butterfly vertical and fast idle screw all out (not touching linkage) and having it idle at 1800rpm:
does the throttle linkage hit the bolt. with that i mean can you adjust the rpm with the curb idle screw? if yes, what happens if you bring her down to what she should be.
you say she get's plenty of fuel. can you see fuel inside the carb when she's idling? if yes, that's wrong.

maybe it's just a mechanical problem the carb linkage itself? the linkage on those cars go bad (specifically at the end of the rod where the joint is that leads down to the rod of pedal). maybe when you accellerate slowly the throttle sticks at 1800rpm and when you rasp it she goes the full way to the stop where the car stalls because it's not set correctly.
ya. on that thought check the linkage, it might just be sticky. when idling at 1800 rpm try to close the throttle further at carb. if you can bring it down further than idle, the linkage is sticking

 

First, I would set choke to full open to get choke out of the equation.
Second, I would check for sticking choke fast idle cam adjustment.
Third, I would look into venturi and verify the throttle plate is closed when throttle in idle position.

 

Im kinda wondering if its a vac leak.

With it at "idle" spray some carb cleaner around the base and housing of the carb front and back... if you hear an rpm change that is the location of the leak.

Rule out vac leak first then we can start on the hard stuff...It only sounded like a choke issue until you said it would die on the rev down. If the plate was blocking air flow it should die on the rev up and it sounds like you've put some effort into the choke side of things. they aren't THAT difficult to figure out.

-Gun

 

To add to what the others have said. After you are certain that its not the linkage sticking partially open. Check your ignition timing. If for some reason you are advanced too far then it cause a higher idle speed.

 

Thanks guys.............no vacuum leak......went that route first.........timing is set......I thinking you guys are right, it's the linkage on the choke.........hopefully I'll have time to play with it some more this week.

Got my Petronix ignition to install.......once I get the screw out that I broke off in the vacuum advance, I'll get it installed.......DOHH!!!!

When it rains it pours........

 

Been running pertronix in two cars for 10 years w/ no problems.
I've left ignition on overnight more than once, by mistake, still no problem.

 

Are you running aftermarket heads?

If you are running big port heads the intake gasket placement is CRITICAL, a little bit off and you have a built in vac leak. We chased that around for a couple of days on my sons Falcon with a 302.

These gaskets can "seem" fine, but there is enough play around the bolt holes that a good set of gaskets can look fine and leak like crazy, my son was sure they were right, but the sealing area was like a 1/8", super thin... and they weren't right.

 

not tyhe linkage on the choke. the throttle linkage. post a picture of your carburetor taken from drivers side so that we can see the firewall as well and I'll point it out