My 1993 7.3l idi 5spd shakes and shudders at startup. sounds like the flywheel. when I give it the gas it will go away. but everyonce in a while
while sitting at idle, it comes back. I also know someone that has a 94 automatic that does the same thing. Is it fuel, or flywheel out of alignment.
thanks for the help with screws shorting out in the cab. never would have figured that one out.
thanks.

 

...bump.... automatics dont have a flywheel, its a flex plate. in your truck though if you think it may be the flywheel, you can always check a few things on it. when you shut down, does it make a clunk? does it shudder when you fire it up cold and warm or just one or the other? you may have air in your fuel lines causing what sounds like a miss. im sure others will chime in there.

 

I wasn't sure about the automatic. mine does it at startup warm and cold.
I don't know about the clunk when I shut it off, because it seems like it has always done that. but I would have to say yes it does make a noise like that when I shut it off.

 

Sounds like the dual mass flywheel is giving up the ghost. I have had good luck using the single mass conversion from NAPA, even though they are made in China. You can get the whole clutch conversion for less $ than for just the dual mass flywheel.

 

ya, dmf is ready to be replaced, that clunk is a great sign of how worn out/broken the springs are inside it.

 

its been doing it for over 2 years. why would the automatic make the same noise.

 

if the automatic makes the clunking noise then your in big trouble. lol... were talking about the clunking noise for you man. could also be the issue with the shudder and shake but again, i think that could be a miss. fuel issue. air in the fuel lines, maybe bad injector. i would do a compression check first, then if those all check out alright fire the truck up and crack one injector line at a time and that will bleed the air out of the system.

 

also, you might wanna press the screader valve on your filter housing, see if air comes out first or fuel instantly. if its air then you have a pre ip air leak. could be a bad lift pump pushing air though the system or a leak in the lines allowing air to get into your system.

 

thanks, appreciate the help. figured mine was the dmf, my buddies automatic, he said it does it almost all the time. mine goes away, but I know what is coming