Major Acceleration Problem...Help
Thread Starter
Burning Brakes
Joined: Jul 2001
Posts: 862
Likes: 0
From: CT
Major Acceleration Problem...Help
My small block has been running great up until yesterday. I had not driven it for two weeks started it up and as I strarted down the road the car was bucking, back firing and breaking up badly. I came home and replaced the rotor, checked the fuel filter, pulled the plugs and found 7 out of the 8 were wet. When I am uup around 2500 RPM it seems to clear a little, but as the RPMs lower it get real bad. Before I had put it away two weeks ago I had added Lucas Fuel Treatment. Up until that time the car had run great. It feels as if I have water in the gas. Could this additive be the problem? I have an MSD systm on the car. I really dont know how to troubleshoot that. I am wondering if I remove the old gas if that will help. I have checked the wires and distributer cap. I am at a loss. Any help would be appreciated.
Thanks
Mike
Thanks
Mike
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
Re: Major Acceleration Problem...Help (My69)
You know, I put some fuel system cleaner in my car about 3 years and the engine promptly exploded. People who were on the forum way back when may remember. :)
I don't know if the fuel is the case, though. Is there any chance someone could have tampered with your car?
-Steve
I don't know if the fuel is the case, though. Is there any chance someone could have tampered with your car?
-Steve
Thread Starter
Burning Brakes
Joined: Jul 2001
Posts: 862
Likes: 0
From: CT
Re: Major Acceleration Problem...Help (Pacin'California)
Steve:
Thanks for the response. I am positivve no one tampered with it. This thing has me baffled. I am hpping it is just the additve. Any other thoughts? What do yoou mean your car exploded?
Mike
Thanks for the response. I am positivve no one tampered with it. This thing has me baffled. I am hpping it is just the additve. Any other thoughts? What do yoou mean your car exploded?
Mike
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
Re: Major Acceleration Problem...Help (My69)
It was a fluke- two days after I put the fuel additive in I threw a rod and punched a hole in the side of my L-48. :) Additive really cleaned those cylinders out!
Melting Slicks
Joined: Aug 2003
Posts: 2,135
Likes: 2
From: Dayton Oh
Re: Major Acceleration Problem...Help (Matt Gruber)
:iagree: with Matt. First thing to do is guarantee you've got proper fuel, fire and timing. You say you had wet plugs so its probably safe to assume you're getting fuel. If you can see a good blue spark at the plugs, then you've also probably got good fire. Therefore, next and easiest thing to do is to check the timing. Good luck :cheers:
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Race Director
Joined: Feb 1999
Posts: 16,978
Likes: 7
From: In Dreams There Is Truth Ohio
Re: Major Acceleration Problem...Help (My69)
Lot of things....maybe blown power valve if you have a Holley, arcing ignition wires...easy to chech that, run it at night, if arcing, you will see that, dirty fuel filter, or water in gas, msd unit going south, plugs, cracked distributor cap. If you are running points, check the distributor plate, check distributor hold down.
Good luck
Good luck
Le Mans Master
Joined: Aug 2000
Posts: 9,662
Likes: 7
From: Semper ubi, sub ubi
Cruise-In VI Veteran
Cruise-In VII Veteran
Re: Major Acceleration Problem...Help (My69)
I agree with George it could be a 100 different things. If I had to guess, I'd say that maybe the fuel system cleaner knocked some sludge or corrosion from your gastank or fuel lines and maybe plugged your filter.
If you are running a Q-jet there is a small filter inside the inlet of the carb. It is either a smalll paper filter or a porous compressed metal of some kind. Those things will plug you off quick. It also could have flushed some sort of deposits out of your car that plugged off your jets,
And after two weeks of setting there could be some water in the tank either from rain if it was outside or condensation if there were any fairly major temperature changes.
If your 69 is like mine you can get a flash light and see into the tank pretty easily, look and see if you see anything that looks like water in the tank.
If you are running a Q-jet there is a small filter inside the inlet of the carb. It is either a smalll paper filter or a porous compressed metal of some kind. Those things will plug you off quick. It also could have flushed some sort of deposits out of your car that plugged off your jets,
And after two weeks of setting there could be some water in the tank either from rain if it was outside or condensation if there were any fairly major temperature changes.
If your 69 is like mine you can get a flash light and see into the tank pretty easily, look and see if you see anything that looks like water in the tank.
Drifting
Joined: Nov 2002
Posts: 1,665
Likes: 1
From: Ontario
Re: Major Acceleration Problem...Help (My69)
Here's a guess for ya - Your fuel treatment loosened up some particles in your fuel lines. These particles eventually made their way to the needle and seat in your carb. Now your needle or seat are scratched or somehow stuck open, resulting in gas flooding into your intake resulting in an extremely rich mixture. This could explain your wet plugs and rough running engine at lower RPMs. Look into your intake through the carb and see if it is flooded with gas. Unfortunetely the only way to check your needle and seat is to pull the lid, primary rods and float from your carb (I am assuming you have a Quadrajet). Like I said this is just a guess, something you could try if all the easier things don't get you where you want to be. This is interesting, let us know what the fix is. Good Luck :thumbs:
