CAR LOSES POWER WHEN ACCELERATING HARD

L

lunarboy

New Member
My V8 has jsut been fully serviced as it wasn't running right - the choke had been slightly stuck on so new choke cable fitted-the serviced inc new plugs, filters, traps, oil, anti freeze etc so running well enough until i accelerate hard - the box kicks down car starts to accelerate and then doesn't really appear to do much else. Reduce acceleration and car runs ok again. Thoughts? BTW It has lumenition so ruling out points ... :) anyway v frustrating - if there is already an appropriate thread just point me in the right direction Cheers
 
first stop in situations like that is always dashpot oil - has it got any?

Next would be mixture checking.
 
OK Guys - starting with dashpot oil - where should they be filled to - the narrow tube is full that the damper goes into - is that the correct measure - the book talks about 1" below the top but is that of the narrow reservoir or the broader area?

Checking full throttle - i will double check

Fuel starvation - most likely causes to start with ? :?

Cheers
 
When stationary will it rev easily and freely to the rev redline?
When driving pull the choke out a little and see if that cures it!
Did they fiddle with the carbs?
What model SU carbs have you got?
If pulling the choke out a bit cures it you may need to richen the carbs by 1/4 turn and try again.
 
damper oil is 1 inch down (I normally fill it to the bottom of the threads) from the top face after the rod is screwed out. If you put too much in it throws it out the top anyway. If there's oil in the top (narrow) bit then it's probably OK.

try the pilkie list next. Does it do it without kickdown (start from slower, leave it in gear and floor it)

re fuel starvation - check the filter's OK as a first step.
 
and another point is what oil is in the dashpot? 3 in 1 or 20/50?one of my dashpots came undone , car was ok until i floored it then blurrrgh!first thing is to look where people have been anyhow,good luck ,rich
 
Ok - if the rain stops for long enough :( I will get the car out and go through all the areas mentioned. I'll let you know - cheers for the help
 
mine is similar, coughs and splutters a bit at 40 and under hard acceleration i get a big miss, checked plugs and leads, so waiting to check carbs, and tune, if that doesnt work, would be looking at fuel pump to see if thats the prob
 
looks like it has been needing a clean and the mixture made a bit richer ...longer run this weekend so we will see :)
 
Hard acceleration is when a car uses the most fuel,if delivery is a bit suspect it can be OK for the rest of the time but not good enough for flat out motoring.
Check all the filters,the pump and pipes for air leaks and see if that fails if there is any sediment in the carbs.
Trying the reserve tap and making sure the vent to the tank works (take off the fuel cap and listen for air being sucked in) is worthwhile too.
 
I had a very similar problem (documented on her). Thought it eas fuel starvation. It was the coil. Would rev freely while in neutral and then would go fluffy above 4000 rpm in first, 3500 in second (auto box). Test drove it lots and all symptoms seemed to suggest fuel, but I replaced the coil and it now pulls all the way. Cheap fic too as only £15. So buy a new coil just for a laugh and see what happens.
 
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