Technical Acceleration problems on Abarth

[Mikas]

Hello everybody!
Today I noticed something weird on my Abarth (Selespeed).
When accelerating hard, there's a noticeable cut in acceleration when the engine is reaching 4000rpms... And then resumes hard acceleration.
The acceleration also feels underpower when starting from a stand.
I don't know if that's something related with the automatic clutch Or some problem with the variable admission.
But this behavious is new to me and there must be something wrong.

Another thing:
I'm used to have a 'sporty' drive mostly in the city, but I'm not sure if making 15L/100Km (less than 16 miles per galon) is normal for this car. ...and the onboard computer tells me the comsuption is even higher than that.

Any suggestions anyone?

Thank's in advance!
Michael

 

[pjp]

Firstlty there is no variable transmission - its a standard 5 speed gearbox with a robot controlling the clutch and gear shift. Clutch is normally fully engaged by about 1500rmpm, you can feel it, and see it on the tacho.

The fuel consumption look real bad - I average 25mpg, a bit of that around town and some on the motorway - some would day I'm not a gentle driver either

I have an idea on this - I'll consult the Workshop manual and get back to you

Paul

Stilo Abarth 3dr, Broom Yellow (Nov '03)

 

[Mikas]

Something went wrong with my reply (no login).

Originally posted by pjp
Firstlty there is no variable transmission - its a standard 5 speed gearbox with a robot controlling the clutch and gear shift. Clutch is normally fully engaged by about 1500rmpm, you can feel it, and see it on the tacho.

Yes I know that. It was a translation problem. English if not my first language. I meant Variable Intake.
But are you saying we can see the clutch operation on the tacho? I can only see the gears changing, is there any other indication I'm missing?

The fuel consumption look real bad - I average 25mpg, a bit of that around town and some on the motorway - some would day I'm not a gentle driver either

I guess that makes us two not that gentle drivers...
The mechanic told me that my milleage was normal for the Abarth. But yours is the second post I'm seeing with very different milleage. The conversion I made from yours 25mpg gave me 9.5L for each 100Km. Unless I'm doing wrong conversions on the net, that milleage of yours seems more like that of a 1.8 Stilo to me. I'm really amazed!

Meanwhile, today I went to the mechanic to see what could be wrong with the acceleration problem. The problem got worst and now it's easier to accelerate faster going easy on the gas, because if you floor it, the engine starts climbing on the revs very slowly and in a non progressive way. i.e. sometimes faster than others. Seems like a clutch related problem, or perhaps ASR malfunction. It doesn't blink though. Let's wait and see, it goes to a complete check next monday.

I have an idea on this - I'll consult the Workshop manual and get back to you

Thank you so much for your help Paul!

Michael

 

[pjp]

Your english is better than my portugese
By variable intake I assume your refering to the so called "modular intake manifold" - Checking in the workshop manual the text states this operates at 4700 rpm, but the diagram indicates 4000-4200rpm. This is supposed to be operated by a solenoid under control of the fuel injection system - maybe if the solenoid was stuck you would get this kind of effect - if you want I can provide transcript of the text.

Paul

Stilo Abarth 3dr, Broom Yellow (Nov '03)

 

[Mikas]

Originally posted by pjp
Your english is better than my portugese
By variable intake I assume your refering to the so called "modular intake manifold" - Checking in the workshop manual the text states this operates at 4700 rpm, but the diagram indicates 4000-4200rpm.

Probably it would be that, yes. I've just read somewhere that this engine has variable intake and I always thought it means that it changes the injection and exaust timings. Perhaps you could explain it better.
And the truth is that something happens at those revs indeed! The engine sounds different and so the acceleration! [}]

This is supposed to be operated by a solenoid under control of the fuel injection system - maybe if the solenoid was stuck you would get this kind of effect - if you want I can provide transcript of the text.

I'm not sure if I would understand it, but maybe there could be others interested. Do as you like, Paul.

Michael

 

[pjp]

Originally posted by Mikas
Another thing:
I'm used to have a 'sporty' drive mostly in the city, but I'm not sure if making 15L/100Km (less than 16 miles per galon) is normal for this car. ...and the onboard computer tells me the comsuption is even higher than that.

My onboard computer is showing 8.8km/l (changed it from mpg temporarily), which I believe is 11.3 l/100km. When I first had the car (and was going gentle) I was getting about 15% better than this.

Paul

Stilo Abarth 3dr, Broom Yellow (Nov '03)

 

[Mikas]

Originally posted by pjp
My onboard computer is showing 8.8km/l (changed it from mpg temporarily), which I believe is 11.3 l/100km. When I first had the car (and was going gentle) I was getting about 15% better than this.

Believe it or not, my onboard computer is giving me numbers higher than the ones I've post. I've made a manual calculation and post my result, not the one from the onboard computer.

Well, let's see if they find what's wrong with my Stilo next Monday.
I hope so!

Michael

 

[pjp]

I'm betting that the solenoid is not operating on the manifold - let us know the result on monday.

Paul

Stilo Abarth 3dr, Broom Yellow (Nov '03)

 

[Mikas]

Originally posted by pjp
I'm betting that the solenoid is not operating on the manifold - let us know the result on monday.

Sure thing!

I'm not sure of what it is because the car goes very well when I'm easy on the gas. As you know better than me, with all that engine power, it goes very fast even with light acceleration.
If I floor it, then the trouble begins. It's like if the computer enter some 'smeagol' mode and start thinking things like: Ok, let's go really fast! No wait, that's too much waste of fuel, let me giving him some time to change his mind. ...Oh, but perhaps he's on a real hurry. ...No, no, better not, on the other hand... what the hell, let's go!


In the end, we'll find a Microsoft bug on the accelerator system.
I'm sorry, the system was designed for gentle drivers only.
...but don't worry, there's this patch to be released next week.

Michael

 

[Lester Piglet]

Hee hee, goodun Mikas.

Les Ross
Certified by a Professional.
03 Stilo 5d JTD80 Active
PSI Powerbox and go-faster turtle.
Metallic Navy Blue

 

[Mikas]

I've got news on this problem.
The only thing the mechanics found to be maulfunctioning was some kind of sensor that measures the amount of air (volume? density?) and gives back that info to the engine's computer.
It's a unit manufactured by Bosch in Spain.

I've heard of this problem on TDIs, but I didn't bought a VW!! [!]

Another thing that's strange is that this unit will only be available on 13th. Why does FIAT needs so much time to deliver this unit? I'm going to try to found out why.

I hope to have more (good) news on the evening of April 13th.


Michael