Thread: 454 engine studder?

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I have a '79 454 in my '69 nova. It was running fine and great (besides needing a new fuel system, working on that) until I parked it on jacks for a month or so to do body work on it.

WHen i got it and and drove it the other day, ir was fine for the first few minutes then it started to studder and chokejust a little bit. I thought it might need gas or something so I filled up, and started and again it was fine. As I drove more, again after a few minutes it did the same thing, and the longer i drove it the worse it got. After shutting it off and restarting it, it would run fine again for a few minutes before progressively studdering more and more.

The car is at the painters for another day, so I haven't had a chance to check things out. I do need to re-do my entire fuel system because it is much too small for the engine (original lines for a straight 6). This hasnt been a problem before though, so i'm not sure why it would be now?

The carb is a tired old Q-jet. I was wondering if the fuel filters were getting clogged but that doesn't explain it getting worse the longer it runs does it?

Please help!
Eric

Originally posted by ericingram
I have a '79 454 in my '69 nova. It was running fine and great (besides needing a new fuel system, working on that) until I parked it on jacks for a month or so to do body work on it.

WHen i got it and and drove it the other day, ir was fine for the first few minutes then it started to studder and chokejust a little bit. I thought it might need gas or something so I filled up, and started and again it was fine. As I drove more, again after a few minutes it did the same thing, and the longer i drove it the worse it got. After shutting it off and restarting it, it would run fine again for a few minutes before progressively studdering more and more.

The car is at the painters for another day, so I haven't had a chance to check things out. I do need to re-do my entire fuel system because it is much too small for the engine (original lines for a straight 6). This hasnt been a problem before though, so i'm not sure why it would be now?

The carb is a tired old Q-jet. I was wondering if the fuel filters were getting clogged but that doesn't explain it getting worse the longer it runs does it?

Please help!
Eric

It might be the filter. If there are larger solids (like rust fromt the tank) floating in the fuel filter They may be floating away from the filter element when it's not running and then re-plugging the filter when there is fuel flow?
Could be the fuel is old or has obsorbed moisture while sitting in the body shop?

Maybe when you had it up on jacks, the crud in the gas tank was stirred up and when youwent to start it the filter caught most of it. Get a new filter and try running it again.

Pretty much what you think it is or what pro said. The engine will start up and you will drive for a ways until debris starts to build up in either the tank where the flow line is, or by the fuel filters. The longer you drive, the more stuff that gets in there and starts to plug up the line. When you shut it off the stuff goes back the line or away from the outlet in the tank, until you start it back up again. The longer you drive the more its gonna shudder. It could be some water but my best guess is debris from inside the fuel system. Changing the filters on the carb or pulling/dropping your gas tank and cleaning it would likely solve it for now. When you install the new system for more flow just make sure everythings clean and the tank is very clean on the inside. Hope that fixes it. Good luck, have fun.