Technical Engine Failure

[js1999]

Hi there, looking for some help please.
My daughter has a Fiat 500 1.2, 2017 with 36,000 on the clock. She drives locally, to/from college and work rarely getting above 40mph for short distances only and the car has been absolutely fine with no issues.
However, on three occasions now, when travelling farther afield for longer and reaching cruising speeds between 60-70mph, the car experiences a sudden loss in power and effectively goes into 'limp' mode. Engine warning lights are displayed and the speed of the vehicle dramatically declines at which point she pulls over to the kerbside and switches off the engine. Twice I have called auto rescue and by the time they have arrived, the car starts again and they scratch their heads and look at her like she's wasted their time. Last Sunday, after 10 minutes down the dual carriageway doing 60mph, it happened again. I went to her aid and after the engine had cooled down (some 30 minutes), we restarted and took it very steady all the way home. Today the car has started normally for a short trip round town 30 mph only, no issues. My local mechanic took a look previously, replaced the ignition coil set, but this hasn't addressed the issue unfortunately and I worry it will simply happen again on any journey where she increases her speed for a certain amount of time.
I'm grateful for any guidance you might have so we can get to the bottom of this and restore her confidence once more, thanks in advance, John.

 

[jrkitching]

Hello and welcome to the forum.

Has the cambelt been changed recently?

Have you had any fault codes read?

 

[js1999]

Hello and welcome to the forum.

Has the cambelt been changed recently?

Have you had any fault codes read?

Hi and thanks for responding. Vehicle is regularly serviced and has only done 6000 miles last two years. I replaced the cambelt and water pump when I purchased it at 31,500 miles, Sep 2022. Last two services, no ECU faults. Spark plugs are newish, coolant level is where it should be. Cooling fan operation OK as confirmed by mechanic. Fault code showed a misfire fault on Cylinders 1 & 4 which were cleared by the mechanic after the ignition coil and lead set was replaced.

 

[John202020]

The timing is out, this is classic symptoms of a tooth out, honestly take it to Fiat, yes it will cost but this now comes up more and more when people get anyone other than Fiat to replace it.

Misfire 1 and 4 | FIAT 500 (2007+)

Hi update please help ,my friends fiat 500s intermittent faults not storing in ecu,car cuts out when driving.she plugged in obd scanner when happened straight away and error codes were misfire cylinders 1 and 4.changed plugs,coil pack and leads but same happened again

www.fiatforum.com

Engine issues after cambelt replaced | FIAT 500 (2007+)

Hey guys, my fiat is giving up on me. I had the cambelt replaced two weeks ago as it was due (I was not having any issues with the engine before). The first time I drove it after being replaced, I started to lose speed and it began jolting forward when I slowed down to pull over. The engine...

www.fiatforum.com

 

[varesecrazy]

Hi and thanks for responding. Vehicle is regularly serviced and has only done 6000 miles last two years. I replaced the cambelt and water pump when I purchased it at 31,500 miles, Sep 2022.

Did you plug in.. To align the top and bottom timing inputs?

Often this is missed..

Cylinders 1 & 4 which were cleared by the mechanic after the ignition coil and lead set was replaced.

It has sensed a misfire,
You need to figure out why..

Again timing needs to be ruled out,

Both mechanically And electronically

 

[jrkitching]

If it's only been used on local journeys since the cambelt was changed, and the problem surfaced when it started to run longer distances, it could indeed be a valve timing issue. We've seen this reported here many, many times before.

 

[js1999]

The timing is out, this is classic symptoms of a tooth out, honestly take it to Fiat, yes it will cost but this now comes up more and more when people get anyone other than Fiat to replace it.

Misfire 1 and 4 | FIAT 500 (2007+)

Hi update please help ,my friends fiat 500s intermittent faults not storing in ecu,car cuts out when driving.she plugged in obd scanner when happened straight away and error codes were misfire cylinders 1 and 4.changed plugs,coil pack and leads but same happened again

www.fiatforum.com

Engine issues after cambelt replaced | FIAT 500 (2007+)

Hey guys, my fiat is giving up on me. I had the cambelt replaced two weeks ago as it was due (I was not having any issues with the engine before). The first time I drove it after being replaced, I started to lose speed and it began jolting forward when I slowed down to pull over. The engine...

www.fiatforum.com

Did you plug in.. To align the top and bottom timing inputs?

Often this is missed..

It has sensed a misfire,
You need to figure out why..

Again timing needs to be ruled out,

Both mechanically And electronically

Thanks a lot. My local garage changed the belt, not a job that I could do myself that's for sure. It's true that the three engine power loss occurrences have all taken place after the cambelt was changed so I guess that I need to go back to them. We had quite a long journey back from Kent where we purchased the vehicle and there was no issue on that journey home which was 2 hours and 60mph+ all the way. This thread has already been really helpful and I will revert once the garage has checked their installation. Thanks for your help!!

 

[js1999]

The timing is out, this is classic symptoms of a tooth out, honestly take it to Fiat, yes it will cost but this now comes up more and more when people get anyone other than Fiat to replace it.

Misfire 1 and 4 | FIAT 500 (2007+)

Hi update please help ,my friends fiat 500s intermittent faults not storing in ecu,car cuts out when driving.she plugged in obd scanner when happened straight away and error codes were misfire cylinders 1 and 4.changed plugs,coil pack and leads but same happened again

www.fiatforum.com

Engine issues after cambelt replaced | FIAT 500 (2007+)

Hey guys, my fiat is giving up on me. I had the cambelt replaced two weeks ago as it was due (I was not having any issues with the engine before). The first time I drove it after being replaced, I started to lose speed and it began jolting forward when I slowed down to pull over. The engine...

www.fiatforum.com

Thanks a lot. My local garage changed the belt, not a job that I could do myself that's for sure. It's true that the three engine power loss occurrences have all taken place after the cambelt was changed so I guess that I need to go back to them. We had quite a long journey back from Kent where we purchased the vehicle and there was no issue on that journey home which was 2 hours and 60mph+ all the way. This thread has already been really helpful and I will revert once the garage has checked their installation. Thanks for your help!!

 

[puntodeltathema]

Multiple misfires which only occur at speed is also a known mode of ECU failure. So if the fault continues to prove elusive it may be worth sending the ECU off to one of the repairers on the web for checking and repair.

 

[js1999]

Multiple misfires which only occur at speed is also a known mode of ECU failure. So if the fault continues to prove elusive it may be worth sending the ECU off to one of the repairers on the web for checking and repair.

Thanks for the guidance on this. Will look at this once the cambelt installation is checked. Much appreciated, J.

 

[The Panda Nut]

Before doing anything more expensive try changing the plugs. One of our 1.2 Pandas eat them. I cannot see any reason for it. ALso I have had similar problems with oil from the breather pipes pooling in the inlet manifiold and upsetting the MAT sensor that lives in the end of the inlet manifold. a large piece of lint free c;oth has removed a lot of oil sludge in teh past and made adifference as I think it also wiped the MAF at the same time.. Our cars also misbehave with the throttle body needing a clean. MES can check that the evapouration solenoid valve is functioning correctly. My dealer said that a blocked breather pipe ( in which sits a flame arrester) can also not help. Suggest remobing the short breather hose from cam cover to air box and flushing with carb cleaner. (they replaced mine). These things are quick and cheap so worth trying fistt. My feeling is the cambelt if a problem (unlikely at 10 - 15K) woulod not recover at anytime if it has slipped. I recommend MES from Gendan.co.uk you only need two diagnostic visits to be well ahead financially. I chnaged our coil pack as well even though the old one appeared to be OK. We had a clear run for 35K following these things before it started again.

 

[jrkitching]

My feeling is the cambelt if a problem (unlikely at 10 - 15K) woulod not recover at anytime if it has slipped.

I doubt the cambelt has slipped; I think it wasn't timed correctly when the belt change was done 18 months ago, and it's still in the same (incorrect) position. The problem hasn't appeared before because the car was only used for local journeys; once it started being used on longer trips, only then did it became apparent.

My understanding is that if you keep below 3000rpm, it won't put the EML on even if the timing is slightly incorrect. Above 3000, it has to be spot on.