Only geniuses need apply..... (Non Clio car troubles)

sevenfourate

Devotee of OCD
Paid Member
I'll try to keep this brief, but to give all the facts.

My Sons 2008 1.2 8V petrol, manual Fiat Punto starts playing up.:


Diagnostic check says crank sensor - fitted new. Not alot different
Cam sensor then fitted - better ? Not sure.
My Son then says everytime i go into town its stalling like 20 times. (May be completely unrelated)
I drive it - it appears ok when cold but gets worse when hot and does stall 3 ties towards the end of my journey.

At this point the car sounds well, stops well, goes well, has no dash lights and no fault codes.

My garage try a new fuel pump. A different MAP sensor, this that and the other. No different.
But they do find when the car is ticking over happily in neutral and not moving - you can press the brake pedal a few times and the car stalls. Every time......

So they smoke test the brake servo to see if its leaking. Indeed, the smoke 'erupts' into the car. This isn't normal.
So we buy a tested / warranted great looking used servo. Fitting was intended for Thursday this week. I text mechanic and ask him if he can smoke test new servo before fitting. He does - and says that appear to 'leaks' too !

Right - luckily my wife has a Punto too....albeit alot newer and a bigger engine....but lets drag that to the garage and leak test that servo too out of interest. Guess what - that leaks too. On a car that runs / brakes etc perfectly and is not that old.
So 3 units, 3 tests and all don't appear to be completely sealed units. A Fiat trait then perhaps ?

But where from here ? ABS pump is about all that's left of the brake system to try - IF its not the servo (£200+ to swap over - and with tests being inconclusive perhaps). Seems silly at this point.

Anyone got a freakin clue....cause neither i nor my mechanic really know wtf is going on here !
 
Breather problem causing an issue with air flow sensor? Brake servo pulling air out causing it to run lean/stall? I'd check for air leaks, split pipes, mixed up pipes etc.

Could be a bit far fetched but I can't see what pressing brake would have to do with engine stalling. If it was just a heat issue I'd say failing coil pack or ignition module etc. Good luck :think: