(T) "Panda" miss fire and spluttering problem

Hi all, I wonder if I can call on the vast experience of you all. I have just fitted my new exhaust and have now been able to move onto the next problem. When I load the engine at low revs in particular, she splutters and cuts out till I back off and change down a gear to increase the revs. Also from idle, when I push down on the throttle she is slightly hesitant.

My thoughts so far are:

1) The usual blocked jet in the carb problem!
2) Vacuum advance?
3) There is still a slight leak from the exhaust pipe but not a lot.
4) Air filter looks quite dirty, maybe she is running too lean?
5) Old points might need replacing

I will start to go through this list first thing in the morning, but what do people think is the most likely cause?

Thanks for any help, allways much appreciated!!

Si

Accelerator pump? When you step on the throttle the carb chucks in an extra squirt of fuel to allow time for the extra vacuum generated to pull more fuel through the jets. If it isn't working you'll get that hesitation when you floor it but it should pick up again.

You can check the air filter easily enough - just remove it and see how it runs without. If it's still the same you can rule it out. Most trouble shooting is just a process of elimination until you hit the problem. Try the easiest and most obvious first. Checking the vacuum advance unit is also quite easy if you don't mind the taste of rubber/dirt/grease etc.. Just take the tube off at the carb end and trying sucking/blowing through it. There should be a lot of resistance to your efforts to get air in/out. If you can just blow through it easily them the diaphagm inside is split.

Hope these tips help.

Hi si,
Just cured this on mine (missfire not so much as splutter though) - see 'leave well alone' thread - by opening up the points gap - allen key with tape on tickover - one complete revolution did it for me (clockwise) - tickover much improved, though this has altered the timing as it pinks a little now on hills - am awaiting timing light... though may just undo the nuts and try turning the distributor a bit (when I fig out which way...)
3 would result in slight loss of power not what you describe I would say
Eliminate 4 by taking it out (put it back if it still does it of course)
then by order 5, 4, 1
could be a combination of these last three of course, or:
6) condensor

Oh yes, points. Do check these too. It's also quite easy. Take off the dizzy cap and put the car in gear with handbrake off. Now slowly pull the car towards you and watch them to see if they open and close. Not sure what the gap is for these but it will be pretty small. If they're opening too much or not at all that would affect timing and spark. The flat mating faces of the points should also be just that - flat. If they're all burnt and pitted it's time for new ones.

Well, I have changed the points and all seems to be well. Adjusted the timing too and she's running sweet most of the time. Only thing remaining is the backfiring but its not major.

I beleive that a new air filter, and some remaining exhaust blowing are to blame for this, although I will give the carb a service too if the problem persists!

Now I am off to london for some drinks, and to collect some shiney new wheels for the car! Wish me luck, its the first journey since collecting her

THanks for all your suggestions! They have been most useful. I have not come accross some of the modern day features (relatively speaking) on this "panda".

Cheers!!
Si

Have you taken on another project Si? I spy three cars in your sig pic, thought you just had two.

Yes indeedy, this will become a competition car in the not so decent future. Sports exhaust fitted, and lancia beta alloys to go on too (thanks kev - mandapanda for those!! I am so pleased with them).

Here is a linky to its progress report. It has been banished to the non fiat section for its spanish roots!! I will add a link on my sig for those interested to keep an eye on. Should make sure I have plenty to do for the next 6 months!!

Si

Hi:
Just to confirm that turning dizzy clockwise would -advance- the ignition timing - the spark occours earlyer (10 degrees BTDC), and turning it anti-clockwise would make spark ignition later -retarding ignition timing- meaning that the spark occours almost at the top end of the piston travel (2 degrees BTDC for eg.).
At least thats what i was told...

Cheers guys

Hi
Thought I would just add - only running problem I have had in past 7 years and 25k miles re: splutter (carb model) was blocked jets. Happened 3 times - I could drive round the problem, but wouldn't idle and had to have choke on slightly. Totally cured in about half an hour. If it's backfiring badly with explosions, then 9 times out of 10 it's condenser about to fail - happens more in damp weather as condenser tends to suck moisture in.

Hello, this is my first post, so please be gentle.

I have the sputtering and miss fire problem with my 999 Fire engine (mounted in a 1988 panda 4x4), but it's intermittent.

I've changed: fuel pump and filter, air filter, spark-plugs and leads. The head Gasket blew, so that's all been replaced. The exhaust's also been remounted, so there's no leaks. The carb's have been cleaned out by an AA man (this happened before the head gasket blew), but the problem's still there.

Like i said it's intermittent, and not a problem when she's first started. It starts up when she's restarted after parked, though not every time.

Any thoughts would be very welcome, as it's doing my head in. Could it be something in the fuel tank?

Cheers

just sorted the same problem out on one of our 4x4's son said it would cut out but could be re started first go more often than not. He confimed it would just run out of power. I changed the complete dizzy and yes job sorted either damaged wire inside dizzy or power pack on way out

Worth a go this is - should be fairly cheap and always something to check when you are servicing your car.

Power pack may not be so cheap...but seems likely...or you say an AA man cleaned the carb.....i would do it myself!!!!

Cheers for that, I'll try the dizzy out and pick up some carb cleaner. I suppose this is what you get when you by off someone who drives it once a year

if you can blow though it quite eas, does that mean the diaphagm has split? how do you fix that?