Technical Grande punto 1.2 petrol 2008 CUTTING OUT when coming to a halt

[Arus18]

Hi all,

Intro:
Brief introduction as I am completely new to this site. Been reading loads of posts on here and seen other people get some really expert advice and I've even used the sites tutorials to perform basic tasks on my girlfriends car that I would not have been able to do other wise! The punto is my girlfriends car and I'm desperate to get it sorted for her as I'm starting to feel really terrible for her!

I personally do not know much about cars but I have learnt alot from this forum so I feel that I know a little bit about this particular topic.

Problem:
Grande punto 1.2 petrol is cutting out when coming to a stop at junctions but also when parking and reversing. In my opinion also the car may seem slightly low on power if going up hill? This may not be the case though as I drive a bigger engine turbo diesel and it might just be that I'm not used to it although my girlfriend has said the same thing about pulling off on hills etc and lack of power on hills.

Things I've tried:
The problem pretty much arose maybe a week after I had changed the breather hoses on the punto after there was a smell of fuel entering the cabin. Both original houses had huge tears in and so both were replaced by myself using a tutorial found on here (thanks!) After a week the car went pretty much into a limp mode and was struggling to get over 40mph! And was also cutting out and struggling to start. Garage said it was the crankshaft sensor... replaced that and basically fixed the majority of the problem. Now what we are left with is a *slight* lack of power and also the same cutting out problem (usually after about 5-10seconds) when coming to a halt (both feet on clutch and brake) then when re firing the engine it usually needs abit of gas on the throttle to start otherwise it will just keep whirring and attempting to start without actually firing up. (From cold however usually works fine first time?)

We took it back to the garage they changed the spark plugs which I think was a guess by them but fair enough... seemed to improve a little bit but problems are still here. There are no error codes according to the garage but he took it out for a spin and agreed that it wasnt right as he experienced the same problems and has made a judgement that it could be the coolant sensor.

Additional info:
When I changed the breather hoses the smaller diameter tube seemed ever so slightly a smaller diameter than the one I had changed however I think this may have been that the original one with time has just become looser around the connector and so looked slightly wider.

I have also read about a throttle relearn. Maybe I should have performed this after installing the new hoses as surely the engine wouldnt have been used to a different ratio of fuel to air? (Maybe a load of rubbish but just a thought).

Thanks and apologies for a huge post I just think the more info for you guys the better picture you will have.

 

[nikrox]

I may have missed it,but have you had the fault codes read yet?..preferably on dedicated Fiat kit.
Does it idle smoothly before it dies ?..OR does it feel like its missing/lumpy?..

 

[Eklipze3k]

There may not be any codes to read, but if you're near to one of our members with MultiECUScan it's definitely worth getting the ECU interrogated.
If I had to guess, I'd say you're looking at a split vacuum hose somewhere.

 

[Arus18]

I may have missed it,but have you had the fault codes read yet?..preferably on dedicated Fiat kit.
Does it idle smoothly before it dies ?..OR does it feel like its missing/lumpy?..

Hi nikrox,

Pretty sure the garage has said its showing no error codes however I cant be certain on what kit hes using or whether it's a dedicated fiat one.

It does quite smoothly and very quietly sometimes hard to tell it's even done it!

 

[nikrox]

After a lot of faff I contacted this place on ebay..very helpful man who imho is a diamond. Worked for my problem..https://www.ebay.co.uk/itm/FIAT-GRA...a=1&pg=2059210&_trksid=p2059210.c100148.m2813

 

[Arus18]

Thanks for that... what exactly was the problem with yours if I may ask?

 

[nikrox]

Stuttering,dropping revs,felt like it was going to cut out...

 

[damted]

But wat caused this problems and what actions solved it ?

 

[GrandePunto PL]

That eBay offer name is incorrect. There's no "IAC valve" in the Grande Punto. Idle air is provided by throttle, always slightly open.
This is fuel fumes "EVAP" system solenoid valve. It has some influence on the idle (but should not make the engine die).
It can be very easily cleaned, un-seized. Don't have to buy a new one.
But warning: it can be easily disturbed, popped out of position when you install it or you replace the breather small hose (it's in the same area behind/under the intake manifold). It will not seat properly = major vacuum leak.

Engine cutting out (stalling) when you try to move (1st or R gear) + lack of power uphill are classic symptoms of valve clearance out of spec. And/or ignition system (worn, old spark plugs) and/or serious vacuum leak (intake manifold, throttle, hoses, brake system - servo). But there's more (various sensors, intake restriction, exhaust leak or restriction, not enough fuel, engine out of timing - belt skip or...valve clearance again).

Easiest check would be vacuum test (real vacuum gauge) or MAP sensor reading via FES/MES program.
Idle vacuum should be around absolute +300 mbar MAP sensor reading (or negative, -0,7 bar on the mechanical gage).

For this and future repairs you need MES (program) and ELM327 ("cable", interface) anyway.

 

[nikrox]

replacing said unit cured it...BUT it was a second hand unit.