1968 plymouth fury weird issue. Help! !

[68plymouth383]

So I took my 68 fury out today. It was running great but every so often when I punch it, and it shifts into third gear, and It keeps on pulling, it'll just lay down and act like it's starving for fuel. Today it bogged completely down, I let off the throttle, and it recovered. After that all was well. New wix fuel filter, plenty of fuel in the tank. Carter thermoquad carb. Fuel pump is a few years old. New ignition system ect... please help

 

[The Horvaths]

Sticky floats or needle. Check your service manual, it will how to check fuel pump.

 

[68plymouth383]

Ok, will do. Thanks

 

[67 chrysler300]

Very similar thing has happened to me with my 67 300. When its kinda hot outside and I floor the throttle from a light, It will take off like crazy; then, if I keep my foot in it, it will suddenly bog down like its starving for fuel OR the ignition cut out. I've got a 440 TNT with Edelbrock 750 cfm carb and Mopar chrome box electronic ignition.

After I let off the gas it runs normally again..I had a 2004 Honda Accord V6 and it feels exactly like when I'd floor it and the engine would rev up to the rev limiter. The computer cuts out the ignition to protect the engine from over-revving.

 

[mr. fix it]

for me it's a light to steady throttle on take off is good but if i punch it from a stand still it dies...
I just rebuilt the carb yesterday and it was good for a day and now it is back to doing the same thing...

 

[68plymouth383]

I don't have that issue at all. I can punch it from a complete stand still, and it'll pull like a monster. I'm wondering if my coil is intermittent, or I've heard that sometimes your ballast can cut out. I want to go back to a starvation issue for fuel, but the carb is set up perfectly. It maybe the tail of the fuel pump push rod that everyone keeps talking about...

for me it's a light to steady throttle on take off is good but if i punch it from a stand still it dies...
I just rebuilt the carb yesterday and it was good for a day and now it is back to doing the same thing...

 

[mr. fix it]

put a stethoscope to the fuel pump, if you hear it tapping away really loud this may be the cause...

 

[70bigblockdodge]

Check ground on ecu, my Challenger did this and I chased a fuel problem which was also a partial problem, sending unit was sucking air under a half a tank(pin hole in pick up tube) after that solved I had a partial clog in fuel line. Then I finally found the ground on ECU. Sometimes it takes me a while.

 

[mr. fix it]

another odd ball thing too could be a partially blocked up exhaust.

Give your mufflers a rap with a rubber hammer or your hand to check to see if there are any loose baffles.

 

[68plymouth383]

Ok, I think I've got the problem solved guys. I bought a nos Chrysler harden'd fuel pump push rod, and a new spectra fuel pump. I pulled the current push rod, and it looked a lot shorter measured up. It measured at 3" With a tape measure. New there 3.25... so there's my issue. I swapped it out, and installed a new Fuel pump, and my car runs better than new.

 

[detmatt]

Ok, I think I've got the problem solved guys. I bought a nos Chrysler harden'd fuel pump push rod, and a new spectra fuel pump. I pulled the current push rod, and it looked a lot shorter measured up. It measured at 3" With a tape measure. New there 3.25... so there's my issue. I swapped it out, and installed a new Fuel pump, and my car runs better than new.

Hah!

 

[68plymouth383]

Hah is right my friend. Just like you said previously check your rod folks. The originals do wear out, and your left with some strange issues...

Hah!

 

[67-Fury]

Just like you said previously check your rod

 

[Dobalovr]

View attachment 87250

Aw you beat me to it....

 

[Dobalovr]

Asked my wife to double check my fuel pump rod length (my eyesight is bad) she came back with looks like 8" .....now I know why I married her.,,

 

[mr. fix it]

...LOL!!!!

 

[65 500]

Asked my wife to double check my fuel pump rod length (my eyesight is bad) she came back with looks like 8" .....now I know why I married her.,,

It's metric in Canada, she meant 8mm.

 

[Dobalovr]

It's metric in Canada, she meant 8mm.

Crap stupid metric system....

 

[65 500]

Crap stupid metric system....

 

[mr. fix it]

for me it's a light to steady throttle on take off is good but if i punch it from a stand still it dies...
I just rebuilt the carb yesterday and it was good for a day and now it is back to doing the same thing...

Update to my issue. It was a dumb *** move that I had put the accelerator pump check ball into the wrong orifice. Now it runs like a champ!