Good evening chaps and chapesses.

I have currently purchased and been driving a Cento Sporting Abarth 1.1 for the past 4 days. I bought it when it needed some serious TLC. The head gasket water pump belts and a full service has been done to it. It now idles around 1250rpm which seems ok.

The major issue I have is that when approaching a junction or roundabout when pressing the clutch in the revs drop down to 0 and the engine cuts out.

I have flicked through the guides on here and made sure all the breather pipes etc are in the right places, the ecu has also been reset. It has also had redex flushed through with fresh fuel just in case.

Any ideas what could be causing it to stall?

Thanks

Fuzzy

Have you checked the intake gaskets? Spraying carbon cleaner or something like that around the surfaces?
How does it start from cold?
Does it start straight back up after stalling?

Chris

Yeah all the gaskets are new and they have all been checked for leaks.

From cold it starts first time every time and idles around 1400/1500rpm then settles to 1250 rpm as it gets warm.

After stalling again it starts straight away with no issues. Most of the time I'm still rolling so I can do a quick on the fly bump start to keep me going. I have literally googled and searched the life out of this and can't for the life of me figure out what's wrong.

Idle speed when warm should be 800 give or take.

Overtight throttle cable? (should have plenty of slack), someone messing with throttle stop (check throttle is closed). Failing that, air leak.

I've just fitted a 40mm throttle body on mine, and this has happened twice to me since. Definitely something in that area. I've checked all the hoses, and there okay. Its a new gasket, the only thing is that at first the throttle cable was sticking.....possibly something to do with this?

Has the car been modified in any way? Check the tps and map sensor, make sure the map pipe isn't blocked.
Does the car stall if you rev it in neutral?

Chris

Give the idle control valve a clean.

Cinq999 said:

I've just fitted a 40mm throttle body on mine, and this has happened twice to me since. Definitely something in that area. I've checked all the hoses, and there okay. Its a new gasket, the only thing is that at first the throttle cable was sticking.....possibly something to do with this?

Click to expand...

Likely. If the cable sticks or is too tight, then the ECU and the potentiometer struggle to see what revs should be.

No pipes are blocked and nothing has been modified.. My throttle moves freely and it sits back as far as it goes every time.. When I rev it up on the driveway it doesn't stall.. its only happened when I've been driving it.

OK.

BUT the only reason it idles that high is too much air. This isn't open to debate -- it's a fact. I'm open to other suggestions, as to why this might be, but air leak is by far the most likely.

I had the same problem last year on my '98 Sporting and it was the Crank Sensor.

Reached 139k yesterday - 150k is the target.

you say the head gasket was done, when they fitted the inlet mani back to the head did they fit a gasket? there could be a kink in the gasket if it is there or maybe it hasnt been done up tight enough?.

i had the same problem when fitting a punto 75 tb, it turned out too be a very small hole between the inlet mani and the tb which was fixed with a bit of instant gasket.

theres also 2 alan key bolts on top of the tbh, make sure they are tight or evan take it apart and use a bit of instant gasket to to remove that from the equation.

check all the vac lines are fitted properly, and are free of splits or cracks.. I can tell you if i pull a vac line off the back of my throttle body the car idles at about 1200rpm too.

there is a lovely picture in the guides posted by fingers which shows what all the connections are and what they should be connected to. Go look at that and compare it to your pipes (as they will have all been removed and put back when the HG was changed, i suspect one is not been put back/has split/or placed incorrectly.

edit: i think on the diagram in guides it shows a pipe that should be connected to MAP sensor, this is not usually there on a cento TB, the MAP is taken off a line to the inlet manifold - but my TB does have that pipe and thus it needed blocking off.

GeorgeDamper said:

I had the same problem last year on my '98 Sporting and it was the Crank Sensor.

Reached 139k yesterday - 150k is the target.

Click to expand...

Agree with the above!

Crank sensor might account for stalling, but not, methinks, for high idle.

how could it... surely thats not even possible - all it can do is make the plug spark at the right time, the wrong time or not at all, can't effect idle.

I replaced my crank sensor to rectify the stalling - I didn't have high idle.

They could be 2 separate issues or could the throttle cable have previously been tightened to increase the idle in order to prevent the stalling ?

All pipes checked.. all intake gaskets checked and replaced by myself. My dad has informed me that it was idling high before the headgasket was even done. I've got hold of a workshop manual for it but I'm not sure where to even start when it comes down to it. Weather hot or cold it sits at 1400rpm now at all times.. Still stalls now and again tho when pressing the clutch in. The cam sensor is fine.. and the car has only done 42,000 miles.

Any more ideas?

However many times you say it, no-one believes you. If it is idling too fast, it is getting too much air in there.

Either -- the throttle cable is too tight (plenty of slack), some clown has been messing about with the throttle stop, the rubber nipple has come loose and is buggering everything up, the cable is seizing, the butterfly isn't closing, or, it's a plain simple old air leak.

A vacuum guage might be useful.

As Dave Walker is fond of saying "air doesn't go down a wire" which pretty much rules out any electrical issues.

On MPI cars, it's possible (albeit very unlikely) that the injector O rings fail -- or are replaced with the wrong ones/left out. etc.

Wow I've bought a car with a forum community of idiots. I am mechanically minded and my dad is a mechanic. I attend car cruises shows and events I'm not just some random guy who's bought a cento and knows nothing about cars. I have just done a full head gasket set on this perfectly. Now it was revving high before and it's revving high now. There are no leaks going anywhere into the intake. I've double checked and triple checked. I've read the guides, made sure everything is in the right place, and checked and checked again.