usually late ignition timing could cause this or an excessive amount of fuel in the exhaust system.answer
backfire can be caused by choke not shutting off completely, also could have a bad distributor cap, bad spark plugs, bad ignition condensor, bad plug leads, or to much fuel getting to carburetor system
Consider getting yourself a service manual as it contains many troubleshooting for your car. Comes very handy sometimes.
Can also be caused by crossed spark plug wires meaning they are not connected in the proper order
Listen to the Signs of the Car talking to you,
Is the Backfire coming from the Tailpipe area or the Engine Compartment area?
Signs of backfire can be caused Vacuum Leak, in and around the Intake Manifold Base Gasket areas, and the Carb. Base or Throttle Body Base, and in any of the many different
Vacuum hoses/lines depending on your make or model, "Use Caution with what you use to seek out the Vacuum leaks, as many aresol base products contain a petroleum base
which can cause severe flash fires,
( especially on and around HOT Engine Parts & Faulty or Loose Plug wires )
in Running Conditions.Always RememberSAFETY FIRST,You want to drive it after you fix it,"NOT look a pictures of its chard remains,in a Hospital Burn Ward."
Be Safe Now / Cruise Longer
It could also be the contact set / points gap if this has recently been replaced/ adjusted.
Your car is running too rich.
No! A car backfires because unburned fuel is getting to the muffler. The heat of the exhause system causes the fuel to combust, thus a backfire. A bad alternator will just not charge your car battery.
while driving yur car reduces speed then pulls off with speed and backfires what can cause that
Unburned fuel in the exhaust system causes the backfire from the exhaust pipe.
The main causes of backfire in any car are incorrect ignition timing, crossed sparkplug wires or worn timing belt (or chains and sprockets).
I think you are hearing pressure pops. Not a backfire.
A car can backfire and die if the spark plugs are bad. The car could also have a problem with the timing or the catalytic converter .
a backfire is caused by incorrect timing or not enough back pressure in the exhaust pipe
The timing of the engine is off or the spark plug wires have been hooked up incorrectly.
it doesn't or it shouldent'
Backfire is normally caused by engine out of time, or spark plug wires installed incorrectly.
Out of time.
Too much PSI.
A sparkplug misfiring.
Could be in need of a tune-up.
Its either too much fuel coming from the carbeuator and causing it to backfire or it could be spark plugs wired wrong. try to be more specific on where backfire is coming from. either out of the carbeuator or the tailpipes.
As with any engine, timing, and also carb problems.
It's lean. You have to figure out why.
running lean can cause your 400ex to backfire ..if it backfires on deceleration its lean ...if it pops on acceleration its running rich.====carb issues