Backfire under acceleration

[ally123]

I've recently purchased a project car 1995 vs 5ltr statesman was recently driving it and was driving well. Parked in the shed for couple days and went to drive again noticed that under acceleration it was hesitant and back firing really loud and stalled on me twice but slightly tapping the accelerator would get me going otherwise it would just konk out could this be ignition module or something to do with ignition

 

[bluehighway]

If its stalling /cutting out /misfiring/ under acceleration (as it gets worse it will be hard to start backfire and stall ) but able to crawl tapping or going very light on the accelerator ...it could be the fuel pump is stuffing out...pop the fuel filter out of the fuel line and check too see if its black stuff that comes out when you tip the contents of the fuel filter out into a container...this will tell you if the pumps ok...if its clean fuel its likely something else just remember which way the filter goes ...its ok to put it back on if its clean... (not sure of the location as I have different car but im guessing up around the diff head somewhere near the tank. If it is the pump theres likely threads here on changing it... or youtbe...

 

[Immortality]

Tapping the throttle gives it more air which might suggest it's rich so it might be a leaking fuel injector or a stuffed fuel pressure regulator diaphragm letting fuel straight into the intake manifold via the vacuum reference hose.

Pull the plugs and see what they look like.

Does it smell really rich in the exhaust?

 

[ally123]

Okay was going over leads and found that number 4 has been arcing to the block big crack and split in the rubber cap. Will be getting new leads and fuel pump as I've done the fuel filter recently it will start and idle fine but under throttle it backfire

 

[BlackVXGTS]

Hold off on changing the fuel pump until you have explored all the other easier avenues, as it's a ba*tard of a job, and you have to drain petrol out of the tank beforehand. If you don't know the maintenance history of the car I would suggest that you replace the spark plugs as well as the leads. An hairline crack in a spark plug can also cause your symptoms. Make sure you replace (or at least inspect) the distributor->coil lead as well as the others. I'd also strongly suggest that you relocate the ignition coil onto the strut tower to minimise any future grief of it fails. Pic of my wife's VS Clubsport below:

 

[ally123]

Tapping the throttle gives it more air which might suggest it's rich so it might be a leaking fuel injector or a stuffed fuel pressure regulator diaphragm letting fuel straight into the intake manifold via the vacuum reference hose.

Pull the plugs and see what they look like.

Does it smell really rich in the exh

Hold off on changing the fuel pump until you have explored all the other easier avenues, as it's a ba*tard of a job, and you have to drain petrol out of the tank beforehand. If you don't know the maintenance history of the car I would suggest that you replace the spark plugs as well as the leads. An hairline crack in a spark plug can also cause your symptoms. Make sure you replace (or at least inspect) the distributor->coil lead as well as the others. I'd also strongly suggest that you relocate the ignition coil onto the strut tower to minimise any future grief of it fails. Pic of my wife's VS Clubsport below:

View attachment 263984

Hey mate the coil had already come like that it's been sitting for abit got it as a project for myself to eventually take to powercruise I've found old wires burnt out **** connecting to ignition module and heat shrinked, rotor cap on dizzy wasn't on properly so fiddled around with that and number 3 cylinder plug lead had actually burnt out and was arcing on either headers or block just tapped it up obviously getting new plugs and leads went for a drive and I actually had throttle so now I know at least what to expect for now