General Rough Idle

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General Rough Idle

owen454

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New to the board. I have a older gen panda 88 I think.
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And it is idling rough. Today I am doing some love and care.

So a couple of things.

I changed the spark plugs and the oil. When I took off the green carb cover I had some pooling oil around the carb and on the bottom of the plastic cover.
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The spark plugs had a bunch of build up on them but I do not know when they where changed last.
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So the idle problem. When I start i need to have the choke pulled and accel floored. Sometimes it starts rough but almost always takes off quickly. After it is started I can kill the choke after a couple of min as long as I am driving. If I am going to need to stop I need rev a bit then pull the choke back out a bit to keep the revs up. If I do not do this it just sputters and dies. If it does I need to completely floor it and keep the choke off to start it back up.

Any suggestions?

Thanks
 
Its the same with mine, i think its just the cold weather. Keep the choke out for a bit longer, at least until the temperature gauge starts to move
 
Now you have given it new plugs and filter I would start by checking the ignition timing and the points gap.

If these are set correctly and the fuel pump is doing its job (sounds like it is though at the moment) I would suspect a faulty vacuum advance unit or a condenser breaking down.

It will also be worth checking the idle adjustment too with an engine rev counter & gas probe.

Worst case if you run it into a traditional garage (one where they don’t ware white coats and don’t mind getting dirty & know more about cars than the computer tells them) they should be able to give it a full tune up and setup the timing etc for an hours worth of labour.

If you want to get it spot on and are really anal, rent an hour on a rolling road and do it yourself so you know it is right. An hour’s access to a rolling road but without an operator to do anything other than adjust the rollers for you, but with an exhaust gas tester and an oscilloscope to watch the timing should set you back about £70. Well worth the money.
 
Any ideas about the oil in the carb and all over the bottom of the filter? I guess this means oil blowing by my cylinders. I am a bit of a noviced here and have not played with a carb since taking apart a Brigs and Straten motor 15 years ago.

Also to provide more info this model does not have a temp gage and even after 30 min of driving it will still drop out after I kill the choke.

I have been trying to find a good garage to get a tune up but here in France I am having a rough time. Nobody seems to know of a good old fashion garage. I think taking it to the Fiat dealership will just get me a big bill and am worried that they may not have much experience with a older model carb.

Thanks again
Jason
 
If its a small amount no worry its when it starts showing at the back of car you start to worry. I have never found a Fiat that did not show a bit of oil. Now this running out and stopping ie low revs engine then stops, I assume engine is shaking a bit by this time?adjust the gas cable a bit just to pick the revs up but do it when the car is hot.
 
Any ideas about the oil in the carb and all over the bottom of the filter? I guess this means oil blowing by my cylinders. I am a bit of a noviced here and have not played with a carb since taking apart a Brigs and Straten motor 15 years ago.

Not necessarily. If you look at the engine cam cover you'll see a pipe (near the oil filler cap) that runs from the cam cover to the airfilter. This is supposed to re-cycle blow by gases from the combustion process back into the the inlet side to be recombusted. This is only for emission reasons and to reduce engine gases from being vented into the atmosphere.

The disadvantge of this is that it sends a gooey mess into your carburettor and airbox/ filter! That's probably what you're finding - an oily looking substance which is in actual fact exhaust blow by gases collecting and condensating in the top of the carburettor and/ or rear section (near the pipe junction) of the air box.

Also to provide more info this model does not have a temp gage and even after 30 min of driving it will still drop out after I kill the choke.

Check the vacuum diaphragm on the distributor. This has a vacuum pipe running from it to the carburettor and the vacuum advance unit can fail. This makes it impossible to set the timing properly and also affects tickover. It's easy to check the vacuum diaphragm (and also the pipe). Pull it off at the carburettor end and blow through it. If you feel resistance then it is fine. If you don't feel any resistance then either the pipe is split or the vacuum advance unit has failed. Both fairly simple to change and make the world of difference to engine running.

Good luck!
 
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