fingers99 said:

And, then, why should the throttle stop suddenly go out of adjustment?

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Since owning my car never had a good idle, always was slightly high. Had repeated attempts to fix it but never quite succeeded. Only triggered my interest to try to fix it again a month ago when suddenly realised my mpg went down unexpectedly. At this time turned out that the lambda sensor was dead. After changing the lambda sensor the idle still did not improve and also replaced the idle stepper again which also did not fix the issue.

did you try changing whole throttle body

Did not try to replace the body. I did replace all the parts like the idle steper motor, and throttle positioning sensor. I wanted to change the injector, pressure regulator and intake temperature sensors but the replacement throttle body that I ordered recently did not come with that part so I could not do it. So I ended up experimenting with the throttle stop adjuster which seems to have worked. The replacement throttle body that I got looks much more in worse state that my one any way and will need at least proper cleaning if I were to use it. Also without new gaskets and hose fitting kit for all the bits attached to the throttle body I would not do it anyway.

checked cable?

https://www.fiatforum.com/punto/357...-stupid-questions-would-appreciate-reply.html

ultimately unless someone has moved the throttle stop at some point you should never have to move it, ever.. It is possible as a car bought 2nd hand that it has been twiddled by someone once if it has always had a high idle.

I probably would have just tried swapping it, its only a few pipes, takes few mins tops but if it working now just leave it for a while and see if its ok.

Did some extensive test drive today and must say the car drives beautifully. The idle is now just under 1k rpm with engine warmed up and about 900rpm with all electrics on as well. The car sounds very quite now and the idle speed is nice and steady.

what fixed it?

flisko said:

what fixed it?

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Adjusting the throttle stop screw did the trick for me.
Idle speed was about 1.2K steady. Adjusting the stop screw with engine running brought the rpm down to 1K steady. Left it like that and test driven the car today for quite a while and everything runs very well now. Hope it stays like that.

so someone was playing with the cable nuts a?

flisko said:

so someone was playing with the cable nuts a?

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No the cable adjusting nuts do not need to be adjusted as long as the throttle sits on the stop. The stop adjuster is no the same as the cable adjuster.

pic?

flisko said:

pic?

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No I see you want me to do some proper work. I'll see what I can do for you though.

Here is a picture of the adjuster on a throttle body I bought to try to replace my one. You can see the an Alan key inserted into the adjuster.

interesting is that 75 punto?

flisko said:

interesting is that 75 punto?

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No, SPI engine. 75 MPI engine, might also have it though if it uses same throttle body.

Had to do an MOT today as I missed it but got polity reminded yesterday. The good news is it passed with no issues.
The emissions data were too good to be believed. CO = 0.0%, and HC=16.
So I guess what I did seem to have bin a good fix. I must admit the idle speed at the moment is behaving.

hc 16? what is that