heavy stutter when using partial throttle. HELP!

[nampus]

Hello guys,
I've got a problem and I hope someone can help me, my 1.2 super s has developed quite a heavy stutter when using partial throttle.
Somethimes it can be so bad, that when pulling away from standstill the car will just stall as soon as I lift the clutch a little, resulting in pulling away with 3500 rpm and looking like an idiot :blues:
It comes and goes, and it feels like it only happens when the carb is only using the primary barrel, at constant speeds, and with less than about 75% throttle. (when it stutters and I put my foot down completely, the car just starts pulling normally)
The carb has already been cleaned completely, was ok for 2 days then started stuttering again.
When it happens it's usually with a warm engine, but it happend with a cold engine a few times as well.
I have no idea what it can be, everything looks perfectly fine, but something must be wrong.
Fuel filter is clean, oil is ok, plugs are ok, already threw in a bottle of carb cleaning stuff.
Nothing works.
(1.2 super s, without egr or katalysator, about 87000 miles)
I really hope someone can help me, because I'm starting to get a little desperate!
Thanks in advance
Cheers
Nampus

 

[imp124]

if its not electronic ignition i believe some people have had problems with their condensor which i think is near the distributor somewhere, also the distributor cap may need a good clean / replace?

Cheers

Steve

 

[Shaun]

would dirty clogged pipes cause this?

 

[egres_svk]

mine did that too.

when i gave it full throttle, sometimes it stopped stuttering, because the vacuum advance changed timing a little, what was enough for dizzy to deal with the damaged condenser and points and work for few moments

first check all the vacuum pipes - might be a crack in some of them

second, take off the distributor cap, check the contacts. if there is some kind of residue, try to scratch the surface a bit to remove it.. same with the rotor arm contacts

third and probably most important, get the dizzy out (will make work simpler), get the points out and also, if you can, measure the capacity of condenser.. if you can get a hold of those 2 items for a good price, replace them, if not, try to atleast clean and grind the surface of the points.. for testing purposes (if you cant get the condenser soon enough), it is possible to buy regular condenser with capacity around 220uF for AC voltage - check local shop with electronic parts ("radio shack" or what).. after changing it should help..

 

[superls]

mine did this, i swapped the carb, still did it, changed the dizzy and ht leads and coil and capacitors, still did it, changed the plugs and it stopped it.

 

[nampus]

Thanks for the replies guys!
The distributor and the points have been cleaned only a few weeks ago, and that didn't help.
Changed the plugs this morning, went ok for about 20 miles and then started stuttering again.
So I'll go and check the vacuumpipes as soon as I get the chance.
Again, thanks for the help!

 

[egres_svk]

Thanks for the replies guys!
The distributor and the points have been cleaned only a few weeks ago, and that didn't help.
Changed the plugs this morning, went ok for about 20 miles and then started stuttering again.
So I'll go and check the vacuumpipes as soon as I get the chance.
Again, thanks for the help!

have you also checked the condenser? just in case, try to measure resistance of coil and HT leads - even low cost multimeter for a few quid does the job

 

[nampus]

Thanks for the help guys.
Problem seems to be solved, got a ma10 carb from the scrapyard fitted and is the car is doing fine again.
Cheers

 

[Shaun]

Thanks for the help guys.
Problem seems to be solved, got a ma10 carb from the scrapyard fitted and is the car is doing fine again.
Cheers

ah so it could be the carb.... time for a cleans me thinks (Y)

 

[Nismok10]

ive been having problems with my super s.. i think its carb its all be apart and cleaned its the fuel air ratio solenoid valve.. .. it went on the dyno and got 70.5 bhp running rich.. so im going for a new auto grassing inlet mani and weber so i can get easy 85bhp

 

[Shaun]

ive been having problems with my super s.. i think its carb its all be apart and cleaned its the fuel air ratio solenoid valve.. .. it went on the dyno and got 70.5 bhp running rich.. so im going for a new auto grassing inlet mani and weber so i can get easy 85bhp

ah cool that would be nice, so you never got the carb sorted then :down:
you still keeping the car shiny after the paint job?