Hi,

I have a problem that I hope some one here can give som new ideas for. The problem is that when I lift off on the accelerator the car misfires and stutters. The the car has been to a local Fiat shop and the manifold has been changed since there was a leakage, also the lambda and the spark plugs has been changed and the compresion has been checked. I think that the engine gets too much fuel but I don´t know what the problem could be? Could it be the injectors? Or the throttle position sensor? The strange thing is that the problem only appears now and then and not all the time. Also the idle is a little bit rough but not so that the cars stalls. When accelerating the car goes perfect but on lift off or on steady gas the stutters appear.

It really annoying so any tips and ideas are more then welcome!

You have to excuse my english by the way

Patrik
a swedish barchetta driver

On lift off, it sounds like it could be a problem with the throttle body being dirty. I was advised to clean I with carburettor cleaner, which solved part of the problem. It only takes a few minutes and is probably best achieved with an old toothbrush.

Let me know if you don’t know what a throttle body is and I’ll see if I can find the Swedish word for it.

Matt.

Thanks for the advise. I will definitly try that. It actually seems logic as the injection warning lamp never goes on when the problem appears and I think it should do that if there were any problems with the injectors or any of the sensors.

Patrik

I have now cleand the throttle house and the car drives like a dream Many many thanks for the tip

That is good news. You're most welcome for the tip, it came to me from someone else on the forum.

Matt.

No joy that lastes for ever Have tried the car a couple of times more and it runs fine as long as the weather is hot and the air is dry but when its damp outside it runs uneven and misfires. Could it be the air flow meter?

Have also noticed that it sometimes smells of petrol in the trunk but, dont think that has anything to do with this or?

Forgot that the problem is more common in higher speeds. That is on the motorway and so.

Sounds like the air flow meter to me.

I had the same problem on my Alfa 156 2.0TS which is a similar setup to the B engine.

John

Hello again!

You could of course clean the mass air sensor too, and re-check the throttle body to see if it's become dirty again.

To my way of thinking there are two different symptoms:
1. Juddering, where the car feels like you're in the wrong gear and is about to stall. If it's this it often happens when you lift off the accelerator, or if you're driving at low revs.
2. Mis-fire. This is a bit different! The engine clatters slightly as one of the cylinders is not getting a proper explosion. The car feels reluctant to pick up speed, but might suddenly surge ahead as you start firing on all four again.

The first problem is typically caused by:
a. Dirty throttle body (including spring).
b. Poor quality petrol.
c. Poorly connected air-intake after the mas air sensor. If you get an air leak, the air-sensor is no longer reporting the right value.
d. Mal-functioning/dirty mass-air sensor.
e. Problem with the oil breather splitter.

Possible solutions are to clean the throttle body and spring, check the air-tightness of the air intake system, clean the mass-air sensor. If it's not that I'll post a picture of the "oil breather splitter', as I call it.

The second problem is more likely to be electrical. Things to check are that the spark plugs are correctly fitted and dry. Also check that your leads are dry and not cracked (was it a damp morning when you had the problem?). Of course the spark plugs might be faulty.

I'm not an expert, so others might feel I'm being over simplistic, or am on the wrong track. I won't be offended if someone comes up with a better idea, but the above reflects my experience with the Barchetta thus far.

It's also hard to describe the problem without using too many colloquialisms, but I tried!

Anyway, good luck,

Matt.

Thanks for all the tips. Now I have cleand the air mass sensor, checked the throttle house again, changed the throttle sensor to a new one, checked for air leakage and checked the sparks. Hopefully it will work but fine now...

The oil breather splitter, is it the one on the top right of the engine that goes in to the air intake? Beside that it could break and leak, what else can be wrong with it? Is there a filter or something in it?

I don't think there's anything inside it. The problem I had was a small crack which only opened up once the engine was hot. It was quite difficult to diagnose until the crack got big enough that the oil started appearing on other parts of the engine.

Another problem you can get is that the breather part becomes blocked with sludge. That's fairly easy to check though.

Anyway, let's hope all your hard work has fixed it!

Well, now the cars seems to run ok. Will take it for a longer drive this weekend to test it properly. It passed the swedish MoT yesterday anyway and the exhaust values (CO (on idle and 2500 revs), lamda and HC) was perfect so it realy should be alright I think...but I won´t take out any victory in advance so a proper test drive will be necessary!

Since last I have driven about 1000 km and the car runs perfect, again many thanks for the tips.

Unfortunatly some idiot broke in to the car last night and demolished the ignition and steeringwheel, the dorrlock, stole the stereo and my ipod. With other words, no barchetta driving on my coming holiday

rylander said:

Unfortunatly some idiot broke in to the car last night and demolished the ignition and steeringwheel, the dorrlock, stole the stereo and my ipod. With other words, no barchetta driving on my coming holiday

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I thought Sweden was a relatively crime free country!

Sorry to hear about that. I hope the insurance covers it!

I thought Sweden was a relatively crime free country!

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Well, not that crime free unfortunatly!

Sorry to hear about that. I hope the insurance covers it!

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Thanks! And yes the insurance covers it.

Probably a Danish criminal I imagine Some XYZ person smashed up my wife's car when we were in Italy, the insurance paid, but it's still not nice and it takes time to organise.....

Probably

Know exactly what you mean, its a lot of work even if the insurance covers everything.

But you have to try to se things from the bright side and since the car probably won´t be ready for my holidays I have to by someting else...mayby this one:
http://www.blocket.se/vi/12483043.htm?ca=11_s

For those of you how don't read swedish its a absolutly perfect 131 for only 12.000 SEK (that about 1300 euro or 900 £)...not to bad

Looks like somebody has looked after that car. Good value for money!