Hello folks,i wonder if anyone can shine some light on this?
Noticed a few times now when accelerating up to about 60mph all is well but when we coast on a light throttle after getting to 60mph the car starts shuddering like a misfire,wont accelerate to a higher speed.Today it happened again but this time cut out to.After stopping it restarted no problems.This fault might not happen for a week.I suspect it could be an injector with excessive static leak back and thus lossing fuel pressure.No fault codes at all.Any more ideas before the injectors come out to be tested.Shes only just turned 50k to.

I don't think it's injector-related, it sounds much more likely to be EGR valve issues as the valve should operate at around 60mph in 5th. My 2.4 had similar issues which went away after replacing the EGR valve. The injectors on these engines are generally reliable and should not be giving problems after such a low mileage. Given the relatively low cost of an EGR valve (look on ebay, it's the same as a 1.9 16V one as fitted to the 1.9 DTH Vectras etc) and how easy they are to fit, it's got to be worth a go. Mine's now done a further 40K with no recurrence. If it's the same 'vibration' I was getting then it almost feels like a driveshaft joint's gone. I was able to clear mine by manually dropping two gears and getting the revs up, the increased pressures in the manifold then got the valve to close.

Please let us know how you get on, hope this helps.

Oh, forgot to add - if it is injector-related, it might be worth running some injector cleaner through it, along with a tank of BP or Shell fuel, as these engines seem sensitive to 'supermarket' fuels.

Thanks for the info.Took it to a friend of mine today to put it on his diagnostic machine.Guess what no faults logged.
I think its either EGR related or fuel related.Whilst we were there today we looked at the fuel correction values.Seems the values are well out and whilst reving it up it had a misfire.
This has lead to us removing the injectors for testing,we then found another problem.Numbers 1,2,3 came out freely,4 and 5 were siezed in the head due to carbon which had come up the injector sleeve.
We managed to get them out with a puller but the bottom copper washer has failed.Maybe something to watch out for?Anyway their off getting tested.I might put an EGR on in any case.Thanks for the help.

EGR problems do not log any faults, EGR is dumb and doesn't communicate back to the ECU. So when it sticks, you don't get any codes. Take the EGR off, see if the rod is moving freely and clean it or buy a new one, it's the most common problem on the forum.

EGR is pretty dumb but if the EGR valve sticks closed or the EGR flow is too low then the ECU will flag a fault.

Similarly is the EGR solenoid/wiring goes open circuit.

After taking advise of "do i dont i",i bought a new egr valve today from ces and fitted it this morning.The injectors came back this evening so ive just fitted them too.The only problem my man could find was they didnt run right on idling,which it was a bit rough on idle.Im hoping with numbers 4 and 5 being loose in the head might have something to do with it to.All the injectors are now tight in their sleeves now and with fresh sealing washers.So we will see how she goes now fingers crossed.Come sunday we will be leaving this country with the caravan for two weeks.Lets pray.

Did you put the injectors back in the cylinders they came from? If not then I would do so or failing that use FiatECUScan (or similar diag tool) to correctly register the injectors to each cylinder.

Yes i numbered them before removal and fitted them back in the same place to save injector classification.Thanks to everyone for the input,i felt a bit disheartend earlier this week,although im a diesel engineer myself but on industrial applications these little ones are a mine field and in all honesty im not familar with car engines,the fuel system is the same as some of our units but thats it.I dont want to speak to soon but its done 150 miles today,so once again big thanks.

might be your clutch slipping, our croma was still juddering after i had changed the egr valve, and cleaned the map sensor. cost us £1056 new clutch, flywheel and cylinder. we were lucky though... mechanic showed me part all cracked and said if it had broken would have taken out the gearbox / transmission, so be careful

Hello guys,arrived back today with croma still in one peice.But we still have the problem although nowhere near as bad.It has only done it twice in 2weeks.It seems if we leave it ticking over for a while before we set of its ok,if we set off straight away it seems to do the judder which could last for now maybe 5 seconds,as though its temperature related.Ive tried switching the box to manual but makes no difference.I still dont know wether its engine or gearbox which is at fault as we still have no warnings.
Does anybody know wether two temp senders are used,like one for the dash,and one for the engine ecu?
I spoke to my helpfull Fiat agent whilst on holiday and their thinking along the lines of inlet manifold swirl flaps.
Thanks guys

Just out of interest, did the judder happen when you were towing or solo?

Hello mate,only when solo absolutley perfect with van behind it but then it had been left running for half an hour for the kids getting set up with their tv screens.In all honesty i cant knock it for the way it performed towing the van,never short on power.My other thought is the gearbox not selecting gears as it should because the engine speed never seems to alter when it does it or that is what it feels like.And we still have this gearbox whine when the revs drop down to say 1300rpm.It then changes down and the noise goes,i dont think the noise has got worse though.Puzzled to say the least.Sooner or later it will have to put a warning up,im going to wait until next time it happens and try and keep it going for as long as poss to get it to try and put a warning up.Perhaps the ecu in question needs to see the fault for 10seconds before it puts a warning up.

I have a 2.4, and the gearbox makes slight rattle sounds as its "thinking", about to change gear, I think this is fairly normal.
I recently had a glowplug error only at startup, slight misfire, and the glowplug warning would come on about 20 seconds after starting for perhaps 30 seconds.
Glowplugs were renewed, one showed an error. The mpg has improved by about 5-8%, but had an ECU reset as well. Previous mpg about 40.
At 1300 rpm it is surely looking for a gear change.

Hmmm...got me puzzled. Not about the gearbox (they all do that, sir, especially from 6th to 5th - the car hangs on far too long before dropping down and whines while doing so, mine's done this for the past 65,000 miles and these days I change down manually to avoid the noise ), but the vibration. If it was swirl vane I'd expect a warning light or error code, the ECU keeps a good eye on them. Might be worth having a look at your inner driveshaft joints for signs of excessive play.

As for your temp sensors, there are three for the air side of things - one on the driver's mirror for outside air temp readout on the dash, one in the MAF for incoming air temp and one in the inlet manifold for intake temp. If you can connect to the car using FiatECUScan (do a search on here if you're unfamiliar with this) you can see the readouts from the sensors. There is only one for the water temp, from memory I believe it's next to the thermostat on the 2.4 engines. The ECU provides the signal for the dash gauge.

There is a possibility that the MAF could cause such symptoms but before spending money I'd hook a laptop up to the car and go for a drive to see if any weird readings manifest themselves. Just to confirm - the judder happens at about 60mph and doesn't go away even if you drop to third and rag it?

Finally, set the onboard computer to 'instantaneous mpg' and see if there is a noticeable change when the judder happens. In the absence of warnings, all you can do is try and get as much information as possible. Sorry I can't be of more help at the minute.

Just spoke to the wife,on the last bad occasion she switched to manual and pulled it down to 4th still juddered,then up to 5th same again,then 6th same again.She pulled over put it to park.At which point it was still shaking and farting.It then put a warning up but she cant remember what it said.But possibly it said "fluid level low"followed by an R.This letter being the first letter of a word but she cant remember the word.She panicked and rightly so.
We,ve now had 5days of trouble free motoring again with it.I wounder weather something goes on were after a repair it has to settle down again?
Very strange,also i think the fuel pressure is a bit low we monitered it with a snap on scanner,at tickover we had 270 bar,i would expect 380 to 400 bar on this bosch system.We see very similar systems (EDC15) and minimum is 380 bar.Does anyone now if this is right.
Thanks again seth

Hi guys a bit of an update.I ended up booking the car into our local fiat agent to see if they could shed some light on it.Funnily enough they found a fault code in both the transmission ecu and engine ecu even though it never put a warning light on that i know of.
They have now carried out a download for both ecu,s.I presume this an updated software version?Fingers crossed.
On a better note i hope,while we were there i ended up treating the missus to a new 500.Not a twin air but a 1.2 pop,which still promise 65mpg and £30 a year road tax.At least it,ll take the croma off the 2mile school run which can,t be helping it.
cheers seth

What were the fault codes?

If I'd known your car was doing a 2 mile school run, I'd have advised you to stop - cars like this (i.e. modern diesels with a DPF) really don't like doing lots of short journeys. Having the DPF regenerate at certain conditions (high load, low RPM - i.e. about 60-65 mph in 6th) can cause the car to run unevenly, especially if the injectors are a little clogged and the EGR valve is past its best...

It'll be interesting to know what the codes were, to see if further action is required.

Hope you enjoy the 500, I'd love an Abarth but I don't think it would tow the caravan too well

Hello mate.Just looked at the bill.All it says is carry out software download for engine ecu and gearbox ecu.OMG i wonder if it was just doing a dpf regen all the time?
I do hope the 500 is ok for her,we pick it up on saturday.she has fancied one for ages,just cant believe we,ve gone back to a petrol engine but needs must and petrol is cheaper too.
Fancy going to Gayden in september,any other croma owners going?
Thanks for everys ones help on this one.
seth