84Capri

I've had a hesitation problem ever since I put my Holley Street Avenger on. When I first put it on, the heat shield wouldn't allow a good seal on the intake, and I had HORRIBLE hesitation. It would just about die when I pressed the peddle any further than 1/10th the way down. I removed the heat shield and rebolted the carb down, and it was night and day difference, but I've still got a little bit of hesitation.

If I floor the peddle from idle the RPM's will drop dramaticaly, and stall 1/2 the time. Any more than 1/4 down on the gas and the RPM's drop (no where near stalling, but about 200-300 RPMs) until either I let up a little, or pump the peddle.

It's not too terribly bad if the engine is warm, but when it's cold it's HELL.

How can I check the seal around the carburetor? I was thinking soapy water, but don't really like the idea of soap getting in the block.

Could it be the vaccuum advance? I know absolutely nothing about the vaccuum advance dizzy's, what should I look for?

And lastly, what's an efficient way to test the vaccuum lines for leaks?

'84 5.0 Mercury Capri RS
Reman'd 302 H.O. installed in July
Holley Street Avenger 570cfm Carb
Mallory HEI distributor
Holley 80GPH Fuel Pump (on the block)

Thanks in advance!

67mustang302

Spray brake cleaner. If the idle suddenly surges then you have a vacuum leak. That way you can spray areas and find out where the leak is. Otherwise, make sure your timing is correct, and you may need to tune the accelerator pump and secondary spring.

mjr46

what type of intake are you using?? the factory ford 4 barrel one?? that has the circular venturies?? Personally if you are using the egr plate under the carb..there is a good chance there is a vaccum leak....do as 67mustang says above^^^^^......after that you'll have to start with the primaries and tune that circuit first...starting with the accelerator pump...but remember when tuning a carb car it is important to take not of when hesitations occur..like on accel?? or decel??....at cruise to part throttle..or wide open throttle.....knowing when and how the hesitation occurs will help you know what area of the carb needs tuning

projectresto83

You might want to check out your plugs too and see if you are running really rich. I know on my eddy performer 600 thats on my car is having some issues but I know I am rich as hell. The plugs are are as black as black can get. I can't drive mine at the moment cause of tranny problems, but I am slowly working out the kinks on my carb. I leaned mine out by changing the jets and rods on the primaries and that helped a ton but it is still too rich.

Be sure your ignition is in good shape and your timing is where it is supposed to be also, that is part of my other problem. Mine doesn't like having the vac advance hooked up at all[&:].

WhiteWindsor

When tuning a carb a vacuum guage come's in handy. A vac guage can tell you alot.