Technical Acceleration Issue with 1.2 8v 500

[EJ192]

Hi guys

I've got a issue with my 2010 1.2 500 which started last week. When I accelerate, the car splutters/jerks/hesitates and this slowly smooths out when I pick up speed. It starts, idles and revs standing fine.

I've had an auto electrician look at it this morning and he says there's no codes stored, the throttle body was a bit mucky so cleaned that but he noticed a pipe on the left side of the engine has split. See attached pictures, is this the breather hose? I don't think this hose has ever been changed, I've had the car 9 years.

The problem seem to happen after I filled the car up with supermarket fuel 2 weeks ago. I didn't really use the car until about 3 days after. A few days of having this issue I filled it up again elsewhere to "dilute" the fuel suspecting bad fuel and it might be coincidence but the acceleration issue seem to settle down after then.

That was Tuesday last week. Yesterday and today the problem seems to be coming more frequent now which is now starting to worry me.

The auto electrician wasn't much help and suggested the car needs a service (it's due in January) making sure the spark plugs are changed. The plugs were last changed in 2017 but I only do about 6k a year if that. I have had the oil, oil filter and air filter changed every year since 2017 so not been neglecting the car.

Any idea what this could be? The pipe does look a mess with all the cracking and if it is the breather hose, would this cause the issues I'm having?

Will appreciate any ideas

 

[jrkitching]

The breather hose needs changing now - I'm surprised you're not getting an oil smell in the cabin. It's a known issue with early 500's and yours looks like the original; most of similar vintage had split and been replaced even before the cars were out of warranty.

I don't think changing it will solve the issue (though it definitely needs doing), but changing the plugs might, expecially if they've been in there for three years. Swapping for iridium equivalents (NGK DCPR7EIX) may also help and if you do, you won't have to look at them again for the life of the car. They're due for replacement now, so you've little to lose by trying this first.

Sometimes with an older car, rough running can be down to a combination of a number of tired components. At this age, the ignition leads and coil packs could also both be past their best, but I'm not really a fan of just changing stuff based on guesswork; it can be an expensive way to fault find an issue.

If a breather replacement and plug swap doesn't fix things, use of a proper Fiat-specific diagnostic tool like MES might help work out what's going on.

 

[EJ192]

Yes that hose isn't great! I noticed it starting to deteriorate a few years ago but with having no issues and garages not saying anything to me, I've just left it.


To be honest I'm quite worried how much needs to be spent to get this issue sorted but as you say, getting the hose replaced along with spark plugs is probably best thing to start off with.

 

[John202020]

Idea, change the oil/filter, air filter, spark plugs with Iridium ones, fill the car with Super Unleaded (e.g.. BP ultimate Shell ultimate/super, replace the hose, and check the "thin breather hose to air box" about £65 for parts, then see how it runs after 50 miles or so?