Volvo 340 - Acceleration problems

[Mike_V]

Hi,

I have a volvo 340 1.4 litre engine with electornic ignition and experiencing irregular acceleration problems. When accelerating in any gear, the engine will not rev smoothly as I accelerate. It appears as the engine is mis-firing or short on petrol. With the choke out a little way, it helps with acceleration and the engine runs a little better, but not yet 100%. If I stop the engine, wait a few minutes and start the engine again, the car accelerates smoothly and I have full power again. The next time I start the engine acceleration would be problematic again. The problem began several weeks after I replaced the spark plugs, leads, petrol filter and air filter. The carboretor has been cleaned, but that did not help. I am not sure if it is an electronic issue or air finding its way into the system some where.

Any thoughts?

 

[Tony Stanley]

Hi,

I have a volvo 340 1.4 litre engine with electornic ignition and

experiencing irregular acceleration problems. When accelerating in any
gear, the engine will not rev smoothly as I accelerate. It appears as the
engine is mis-firing or short on petrol. With the choke out a little way,
it helps with acceleration and the engine runs a little better, but not yet
100%. If I stop the engine, wait a few minutes and start the engine again,
the car accelerates smoothly and I have full power again. The next time I
start the engine acceleration would be problematic again. The problem began
several weeks after I replaced the spark plugs, leads, petrol filter and air
filter. The carboretor has been cleaned, but that did not help. I am not
sure if it is an electronic issue or air finding its way into the system
some where.

Ignition problems are often mistaken as short on fuel, it could be one of
the items you have replaced with a faulty unit. It is always important to
use good quality ignition components as these are highly stressed
electrically.

Insulation break down - Causes hesitation/misfire on acceleration. The weak
spark that remains after some of the energy has leaked to ground somewhere
other than the plug, is not strong enough to ignite a large volume of
petrol, but seems ok at tick over.

Check the engine at night with your eye accustomed to the dark and look for
glowing or arcing round the the high voltage components. Also try putting
the old parts back in to see if is a problem with the new parts or perhaps
the way you have assembled them. (eg coil cable routing)

 

[Guest]

experiencing irregular acceleration problems. When accelerating in any
gear, the engine will not rev smoothly as I accelerate. It appears as the
engine is mis-firing or short on petrol. With the choke out a little way,
it helps with acceleration and the engine runs a little better, but not yet
100%. If I stop the engine, wait a few minutes and start the engine again,
the car accelerates smoothly and I have full power again. The next time I
start the engine acceleration would be problematic again. The problem began
several weeks after I replaced the spark plugs, leads, petrol filter and air
filter. The carboretor has been cleaned, but that did not help. I am not
sure if it is an electronic issue or air finding its way into the system
some where.

I'd be putting alot of (monopoly) money on crap in the carb thats being
sucked into a passageway or jet during running and partially starving the
engine of fuel. When you switch off the debris floats away until next time
when its sucked into position.

Tim..

 

[Mike_V]

Tony,

Thanks for the advice. Last night I checked the engine and found that sparks were leaking from what appeared to be the spark plugs of the first 2 cylinders closest to the radiator. I replaced both spark plugs and checked again. I did not see the blue sparks this time. I will test drive it today and hopefully the problem has been resolved.

Thanks once again.
Mike.