Hey there, I built a fresh 440 for my charger a year ago. The engine pulls strong to around 4 grand. after that the engine chokes. It sounds like is is missing and kind of pulses and sounds out of time. Sometimes it sounds like it tries to suck a valve through the head. This would royally suck Where should I look? the problem is fairly recent. Fuel or ignition, timing?....hmmm. Runs great at lower rpms and still embarasses cars in races though. Thanks guys
Mopar Lover
Probably either lack of fuel or ignition.
Since all these cars are getting old, ANYTHING from the tank forward is suspect. Could be rust/ junk in the screen at the tank pickup, collapsing hoses on the suction side of the pump, or junk / rust/ corrosion/ damage to the fuel line anywhere.
Check the pump pressure, and check the pump for flow. Pressure/ vacuum gauges at any automotive store are just not that expensive. You should have somewhere around 5 psi, 3 1/2 absolute min. It would be good if you can safely rig a fuel pressure gauge that you can see through the windshield for testing.
Also check the inlet side of the pump. It should be able to develop a vacuum of at least 10", with the outlet disconnected from the carb.
You should check volume. Absolute min. is 1 qt in 1 min at 500rpm (slow idle)
I asssume you have electronic ignition and not points? Could be bad plugs wires cap, rotor, coil or ECU, just about anything in there that deteriorates the spark.
I'd start by changing the plugs, and use and ohmeter to check the wires.
CRITICALLY look over the cap and rotor for flash over, carbon tracking, cracks, moisture.
If you don't find something there, try another coil.
Also don't forget the common problem now that these cars are getting old---poor connections through the firewall connector. On that note, it is even possible that an ignition switch going a little south might be making poor contact. It would be worth checking some voltages
Since all these cars are getting old, ANYTHING from the tank forward is suspect. Could be rust/ junk in the screen at the tank pickup, collapsing hoses on the suction side of the pump, or junk / rust/ corrosion/ damage to the fuel line anywhere.
Check the pump pressure, and check the pump for flow. Pressure/ vacuum gauges at any automotive store are just not that expensive. You should have somewhere around 5 psi, 3 1/2 absolute min. It would be good if you can safely rig a fuel pressure gauge that you can see through the windshield for testing.
Also check the inlet side of the pump. It should be able to develop a vacuum of at least 10", with the outlet disconnected from the carb.
You should check volume. Absolute min. is 1 qt in 1 min at 500rpm (slow idle)
I asssume you have electronic ignition and not points? Could be bad plugs wires cap, rotor, coil or ECU, just about anything in there that deteriorates the spark.
I'd start by changing the plugs, and use and ohmeter to check the wires.
CRITICALLY look over the cap and rotor for flash over, carbon tracking, cracks, moisture.
If you don't find something there, try another coil.
Also don't forget the common problem now that these cars are getting old---poor connections through the firewall connector. On that note, it is even possible that an ignition switch going a little south might be making poor contact. It would be worth checking some voltages
Thank you sir! I'll get to it this weekend when school is not happening. I'm going to check the ignition first. I replaced the cap, it was firing across, it didn't solve the problem though. There are plenty other variables I know.
Have you heard the story of the cumbersome giant alternator that sits right next to the distributor and somehow affects the spark/ ignition magnetically? I heard it from an old mopar friend of mine.....
Have you heard the story of the cumbersome giant alternator that sits right next to the distributor and somehow affects the spark/ ignition magnetically? I heard it from an old mopar friend of mine.....
