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carfreak09
06-06-2016, 09:09 PM
Since I notice a few turbo owners in here lately, I thought I would bring up this observation and compare to other turbo owners experiences. I've been noticing a prominent hesitation/jerking sensation when accelerating at around 2500 rpms and then again around 2900. I thought at first it was the AC compressor turning on at inopportune times but I notice the same issue with it off. It's highly annoying as the car just refuses to accelerate smoothly when passing those rpms. It's most noticeable in 2nd and 3rd gear and again when in 6th gear and trying to accelerate slowly on the highway. It doesn't feel like it's losing power per say, but it feels like something mechanical happens (perhaps the turbo is kicking in fully) and the car jerks. It's almost like the engine mount is too soft and allows too much engine movement, thus causing the engine to rock backward when the turbo engages and causing the jerky motion. Also, when turning the car off, you can feel the engine rocking back and forth (sort of like a run-on sensation in some old bad running clunker) and you can often hear a metallic rattling noise, like a heat shield or exhaust part is moving around.

Im just curious if any other turbo owners have noticed this jerkiness. My 500 turbo has some hills and valleys to its power distribution in the same rev range but it doesn't get jerky like the X. If others experience this, I'm going to assume the extra weight is just magnifying a bad habit of the small engine.

aelfwyne
06-06-2016, 09:51 PM
Since I notice a few turbo owners in here lately, I thought I would bring up this observation and compare to other turbo owners experiences. I've been noticing a prominent hesitation/jerking sensation when accelerating at around 2500 rpms and then again around 2900. I thought at first it was the AC compressor turning on at inopportune times but I notice the same issue with it off. It's highly annoying as the car just refuses to accelerate smoothly when passing those rpms. It's most noticeable in 2nd and 3rd gear and again when in 6th gear and trying to accelerate slowly on the highway. It doesn't feel like it's losing power per say, but it feels like something mechanical happens (perhaps the turbo is kicking in fully) and the car jerks. It's almost like the engine mount is too soft and allows too much engine movement, thus causing the engine to rock backward when the turbo engages and causing the jerky motion. Also, when turning the car off, you can feel the engine rocking back and forth (sort of like a run-on sensation in some old bad running clunker) and you can often hear a metallic rattling noise, like a heat shield or exhaust part is moving around.

Im just curious if any other turbo owners have noticed this jerkiness. My 500 turbo has some hills and valleys to its power distribution in the same rev range but it doesn't get jerky like the X. If others experience this, I'm going to assume the extra weight is just magnifying a bad habit of the small engine.

Is your X automatic or manual?

If it's an automatic..... Well let's just say that transmission is herky-jerky.

carfreak09
06-07-2016, 12:05 AM
Is your X automatic or manual?

If it's an automatic..... Well let's just say that transmission is herky-jerky.

There is no automatic with the turbo...please read carefully :)

5port
06-07-2016, 08:10 AM
Assuming this wasn't happening in the beginning it could be turbo surge caused by a loose clamp on one of the hoses. Sometimes you can hear the leak. I would think check all clamps first. Here's a similar thread:

http://www.fiat500usaforum.com/showthread.php?18425-Turbo-surge&highlight=Turbo+surging

carfreak09
06-07-2016, 01:57 PM
Assuming this wasn't happening in the beginning it could be turbo surge caused by a loose clamp on one of the hoses. Sometimes you can hear the leak. I would think check all clamps first. Here's a similar thread:

http://www.fiat500usaforum.com/showthread.php?18425-Turbo-surge&highlight=Turbo+surging

Hmmm...interesting. Thanks for the thread. I have had an odd high pitched whistle sound effect when first starting the car in the morning. I thought it was just mechanical whining, but perhaps the whistling is a boost leak somewhere. Are you referring to clamps on the intercooler hoses?

randY49
06-07-2016, 02:56 PM
Hmmm...interesting. Thanks for the thread. I have had an odd high pitched whistle sound effect when first starting the car in the morning. I thought it was just mechanical whining, but perhaps the whistling is a boost leak somewhere. Are you referring to clamps on the intercooler hoses?
I've never owned a FIAT 1.4T, but in my experience with other turbos it is usually the connection at the intake manifold that develops a leak. However, it would be a good idea to check all your intake hoses.

The other thing that comes to mind is perhaps a failing wastegate? Just something else to consider if you can't find a leak in the hoses.

5port
06-07-2016, 03:09 PM
Hmmm...interesting. Thanks for the thread. I have had an odd high pitched whistle sound effect when first starting the car in the morning. I thought it was just mechanical whining, but perhaps the whistling is a boost leak somewhere. Are you referring to clamps on the intercooler hoses?

Yes. All hoses in the path from the output of the turbo ---> intercooler ---> intake manifold.

pkgmsu2000
06-07-2016, 07:16 PM
how many miles on the car now? this is my first fiat, but my previous car was a dart 1.4T 6MT. Same engine and same trans. From experience, we would troubleshoot...

1) engine mounts, upgrading the rear trans mount with a firmer mount greatly helped shifting and stopped the slopiness
2) upgrading bushings in the shifter box
3) adjusting the wastegate *properly* to ensure a smoother boost across all power band, plus installing a boost gauge or Ultraguage to monitor boost
4) checking spark plugs every 20k and replacing them at 25k or 30k, plus upgrading to colder plugs gapped properly
5) having dealer perform all flashes that have been released
6) checking for boost leaks (hoses, connections, fittings) and checking the stock boost solenoid valve (known to be quite faulty if same OEM part)
7) upgrading the factory downpipe to alleviate any airflow restrictions to exhaust more CFM let the turbo actually do some work


again, im still just starting to dig into the similarities between 1.4T dart manual and 1.4T 500x manual, so stay tuned in the next few weeks to see what i learn :-)

carfreak09
06-07-2016, 08:20 PM
how many miles on the car now? this is my first fiat, but my previous car was a dart 1.4T 6MT. Same engine and same trans. From experience, we would troubleshoot...

1) engine mounts, upgrading the rear trans mount with a firmer mount greatly helped shifting and stopped the slopiness
2) upgrading bushings in the shifter box
3) adjusting the wastegate *properly* to ensure a smoother boost across all power band, plus installing a boost gauge or Ultraguage to monitor boost
4) checking spark plugs every 20k and replacing them at 25k or 30k, plus upgrading to colder plugs gapped properly
5) having dealer perform all flashes that have been released
6) checking for boost leaks (hoses, connections, fittings) and checking the stock boost solenoid valve (known to be quite faulty if same OEM part)
7) upgrading the factory downpipe to alleviate any airflow restrictions to exhaust more CFM let the turbo actually do some work


again, im still just starting to dig into the similarities between 1.4T dart manual and 1.4T 500x manual, so stay tuned in the next few weeks to see what i learn :-)

So is yours smooth accelerating all the time or do you run into any brief hesitations like I described? I'm at 9300 miles. I will be taking it in soon to have the loose passenger side power window switch panel fixed, a pull to the right fixed, check the operation of the HVAC to see why fresh air mode doesn't work, and see if my ECU is up to date (I have doubts it is since it was a June build, was driven by my salesman from another dealer and delivered to me on a Sunday when their dealer wasn't even open).

pkgmsu2000
06-08-2016, 09:44 AM
So is yours smooth accelerating all the time or do you run into any brief hesitations like I described? I'm at 9300 miles. I will be taking it in soon to have the loose passenger side power window switch panel fixed, a pull to the right fixed, check the operation of the HVAC to see why fresh air mode doesn't work, and see if my ECU is up to date (I have doubts it is since it was a June build, was driven by my salesman from another dealer and delivered to me on a Sunday when their dealer wasn't even open).

my 500x has a grand total of 54 miles, but i experienced all of the symptoms that you described in my 1.4T dart. let us know what they say about flashing the ECU. the top fix for my dart was the wastegate adjustment, which we found some 2013 darts (1st model year) to be set WAY too low out of the factory. some at the factory were set at 0mm or 1mm, we adjusted them up to 5mm and the 2nd-to-3rd gear "surging" went away during acceleration.

pkgmsu2000
07-06-2016, 08:48 AM
http://www.fiat500usaforum.com/showthread.php?25368-Multiple-recent-updates-make-sure-to-get-them!

post #8, 2nd picture says the EPS update addresses the jerkiness you described at 2500 RPM. im still fighting with my local dealer to get these updates, but they are being stubborn about them because my VIN doesnt show up for the 5 updates.

carfreak09
07-07-2016, 01:22 PM
http://www.fiat500usaforum.com/showthread.php?25368-Multiple-recent-updates-make-sure-to-get-them!

post #8, 2nd picture says the EPS update addresses the jerkiness you described at 2500 RPM. im still fighting with my local dealer to get these updates, but they are being stubborn about them because my VIN doesnt show up for the 5 updates.

Unfortunately, the updates did not cure the hesitation :( Its really irritating.

pkgmsu2000
07-07-2016, 07:46 PM
Unfortunately, the updates did not cure the hesitation :( Its really irritating.

any way to safely post a video of RPMs with sound?

pkgmsu2000
07-20-2016, 04:00 PM
Unfortunately, the updates did not cure the hesitation :( Its really irritating.

check out post #34 in this thread titled "Jerks at 2500RPM". you might want to see about your coil packs which are unfortunately a known issue with 1.4T

http://www.dodge-dart.org/forum/dodge-dart-1-4l-multiair-turbo/30561-jerks-2500rpm-4.html#post478353

carfreak09
07-20-2016, 11:12 PM
check out post #34 in this thread titled "Jerks at 2500RPM". you might want to see about your coil packs which are unfortunately a known issue with 1.4T

http://www.dodge-dart.org/forum/dodge-dart-1-4l-multiair-turbo/30561-jerks-2500rpm-4.html#post478353

Thanks for this info! You know, I was already beginning to suspect a poor performing coil pack as a possible culprit. The info you provided has me leaning closer to it as the jerkiness feels like a minor stumble/misfire and is most noticeable when the AC is on, which is when the coil pack would be under added strain. I guess I could buy one coil pack and start the process of elimination although that would be very tedious. It's that or take it to a dealer further away and see if they will listen to me and actually test the coil packs.

pkgmsu2000
07-21-2016, 10:06 AM
Thanks for this info! You know, I was already beginning to suspect a poor performing coil pack as a possible culprit. The info you provided has me leaning closer to it as the jerkiness feels like a minor stumble/misfire and is most noticeable when the AC is on, which is when the coil pack would be under added strain. I guess I could buy one coil pack and start the process of elimination although that would be very tedious. It's that or take it to a dealer further away and see if they will listen to me and actually test the coil packs.

keep us posted on how things go. im only at 387 miles, but i think you are at 9,000 miles and i am wondering i am looking into the future here...

pkgmsu2000
07-21-2016, 02:06 PM
additional coil pack research tells me that coil packs should always be replaced in sets of 4. The reason is that they all share the same circuit and once one starts going it will start to mess up the other coils also. Even though you have one or 2, the damage may have already been done to the others. FWIW.

carfreak09
07-21-2016, 02:45 PM
keep us posted on how things go. im only at 387 miles, but i think you are at 9,000 miles and i am wondering i am looking into the future here...

Wow, do you drive anywhere?? I do that many miles in 3 days easy! Im over 12k now.

pkgmsu2000
07-21-2016, 02:57 PM
Wow, do you drive anywhere?? I do that many miles in 3 days easy! Im over 12k now.


dont drive much, lol, work from home and take my jeep most places

grosa_2002
07-30-2016, 06:18 AM
This sounds all too familiar. We traded our 2013 500L 1.4L Turbo with Dual Disc Clutch Transmission automatic (kind of). I never did get used to the herky jerkiness of that combination. Anything in the mid throttle range would do this and yes it is boost related. The engine works great in the Abarth, not so smooth in the others. The whistling you hear is likely the turbo itself, it's supposed to whistle and wine a little. It is after all a turbine wheel and a compressor, I'd worry more if you didn't hear the turbo. With a turbo, you need to adjust your driving habits a little. Your either on or off boost and modulating back and forth will produce some power surges. Hope this helps.

Best regards,
George

pkgmsu2000
08-09-2016, 10:31 AM
was it the coil packs?

carfreak09
08-17-2016, 06:05 PM
was it the coil packs?

Tentatively, I'm going to say I think it was. It took over a week to get the coils from Eurocompulsion as they had to special order them. Apparently, the L and X use different (stronger?) coil packs then the Abarth, which could partially explain the higher torque rating in the L and X. This kind of sucks though as dealers may not stock these as they would the more common Abarth. I finally put them in today.

Installing them was a learning experience....first problem I ran into was an engine cover that didn't seem to want to come off. I removed the 2 bolts but the back of the cover was being held firmly in place and I couldn't see what was holding it. Finally, a hard yank got it to pop off. I was worried I would break something! Turns out it's a ball/socket arrangement....odd to say the least. 2nd problem was I had difficulty figuring out the plugs for the coil packs. You have to lift a small black tab slightly, pry a yellow slider towards you, then press the black tab down to unlock the plug from the socket. The first one came off without me fully realizing the process. The second one wouldn't seem to budge even with the yellow slider pulled out. As I was pulling on it, the socket of the coil shattered, thus ruining it as a spare!! :bash: Apparently, I wasn't pushing the tab down to unlock it. Lesson learned the hard way....The 3rd problem was Fiat, in its infinite wisdom, routes 2 crankcase ventilation hoses directly over the top of the left coil pack. I tried removing the one hose from the PCV valve but it wouldn't budge so I decided to unbolt the entire plastic contraption on the right and a bracket that helps stabilize the hoses and try to maneuver the hoses enough out of the way to unbolt the coil pack and pull it out. This worked, probably because I have relatively small hands. I'm not sure if this process would work for everyone.

Initial impression is that the car does seem to accelerate smoother and have more power down low. I have felt a little hesitation a few times but nowhere near as bad as it was. Since the exhaust had already improved the hesitation, it's a little more difficult to say how much of an improvement can be attributed to the coil packs. It cost me $200 to replace them. It will take some more seat time to determine if the out of pocket expense was worth it.

pkgmsu2000
08-19-2016, 10:01 AM
Tentatively, I'm going to say I think it was. It took over a week to get the coils from Eurocompulsion as they had to special order them. Apparently, the L and X use different (stronger?) coil packs then the Abarth, which could partially explain the higher torque rating in the L and X. This kind of sucks though as dealers may not stock these as they would the more common Abarth. I finally put them in today.

Installing them was a learning experience....first problem I ran into was an engine cover that didn't seem to want to come off. I removed the 2 bolts but the back of the cover was being held firmly in place and I couldn't see what was holding it. Finally, a hard yank got it to pop off. I was worried I would break something! Turns out it's a ball/socket arrangement....odd to say the least. 2nd problem was I had difficulty figuring out the plugs for the coil packs. You have to lift a small black tab slightly, pry a yellow slider towards you, then press the black tab down to unlock the plug from the socket. The first one came off without me fully realizing the process. The second one wouldn't seem to budge even with the yellow slider pulled out. As I was pulling on it, the socket of the coil shattered, thus ruining it as a spare!! :bash: Apparently, I wasn't pushing the tab down to unlock it. Lesson learned the hard way....The 3rd problem was Fiat, in its infinite wisdom, routes 2 crankcase ventilation hoses directly over the top of the left coil pack. I tried removing the one hose from the PCV valve but it wouldn't budge so I decided to unbolt the entire plastic contraption on the right and a bracket that helps stabilize the hoses and try to maneuver the hoses enough out of the way to unbolt the coil pack and pull it out. This worked, probably because I have relatively small hands. I'm not sure if this process would work for everyone.

Initial impression is that the car does seem to accelerate smoother and have more power down low. I have felt a little hesitation a few times but nowhere near as bad as it was. Since the exhaust had already improved the hesitation, it's a little more difficult to say how much of an improvement can be attributed to the coil packs. It cost me $200 to replace them. It will take some more seat time to determine if the out of pocket expense was worth it.

solid write-up, thanks for sharing with us. hopefully the $200 was well spent, but its a bit concerning to me that anyone would have to change 4 coil packs at less than 15,000 miles. please, please keep us posted with your experiences going forward. i am still at 680 miles on my Pop, lol. but i am absolutely following your progress to see if your present is my future, lol.

lastly, i can suggest that you just leave the engine cover off in FLA. the cover is a big heat trap for the turbo/engine bay, and im guessing its hot all the time in florida. i use my engine cover in denver winters, but never denver summers.

carfreak09
08-19-2016, 09:35 PM
solid write-up, thanks for sharing with us. hopefully the $200 was well spent, but its a bit concerning to me that anyone would have to change 4 coil packs at less than 15,000 miles. please, please keep us posted with your experiences going forward. i am still at 680 miles on my Pop, lol. but i am absolutely following your progress to see if your present is my future, lol.

lastly, i can suggest that you just leave the engine cover off in FLA. the cover is a big heat trap for the turbo/engine bay, and im guessing its hot all the time in florida. i use my engine cover in denver winters, but never denver summers.

I would agree that changing coil packs at such low mileage is a disappointment. That being said, the hesitation was noticed in the first 600 miles so perhaps I just got a bad coil pack from the factory. I almost did leave the engine cover off but then I noticed the significant sound deadening material on it so I figured it's helping keep the engine quiet. Also, it keeps water and the majority of dirt/dust from getting on sensitive electrical parts, which should help them last longer and look cleaner longer. I'd prefer to replace it with a more stylish engine cover though.

Happy to provide useful info! Us rare Pop owners have to stick together! The service advisor at my huge multi dealer said mine was the first stick shift X he had ever seen. While it's fun to have something unique, it's also a bit scary as I'm always nervous they will think it's a 2.4 and service it improperly. And my fears were realized just last week when I went in for my 2nd oil change. I noticed the receipt said $30 oil change when the last one said $50 (I got 4 free oil changes from Fiat when I bought the car). I thought that was fishy so I called and spoke with the service manager. She assured me that she had noticed the mistake when they went to charge Fiat for warranty and personally asked the tech if he put in synthetic oil in my car. He said he had noticed that I got synthetic the first time so went with that rather then what the service advisor typed in. Since she was aware of the mistake, I feel she was being honest with me. Still, owning such a rare bird can be concerning when it comes time for service.

ronbo10
08-20-2016, 01:11 PM
I've been watching this thread with interest, even though I don't own an X- but do own an L with the same engine/same tune (though with DDCT). Thanks for the thorough write-ups, carfreak09.

Just an observation and a suggestion, which you're probably doing already anyway. I noticed our L starting to get a small hesitation, not off idle, but passing, say, 1700 rpm using part-throttle. This was with about 16,000 miles on the odometer. I generally use 89 Octane, which gives me no apparent issues (though I've heard using less than 91 might have you swapping out your plugs earlier than you might have to otherwise). In any case, with the hesitation (a pretty slight one, really), I ran a couple of tanks of 93 octane, and that seemed to help. At least there's no more stumble, though I suppose it also could have been a bad tank of gas that was causing the stumble, so maybe this was a coincidence- who knows.

Also, I make sure to use Top-Tier gas, a standard which Shell and BP support (my choice in my area because they're easily found)- this ensures your FI system gets the detergents it needs to keep the injectors clean. It's my understanding that Top Tier detergents are only used in Top-Tier supporting companies' premium grade fuel, but given that mid-grade is actually just a combining of the low-octane fuel with the high-octane fuel, 89 octane should provide at least some of that detergent action.

pkgmsu2000
08-22-2016, 03:47 PM
i am always using 91 octane or better, and i am going to always do my own oil changes even though i too get a couple "free" oil changes... LOL nothing in this world is free :-)

Southernroadrunner
08-22-2016, 09:33 PM
i am always using 91 octane or better, and i am going to always do my own oil changes even though i too get a couple "free" oil changes... LOL nothing in this world is free :-)

I got a couple free oil changes and shoe rotations back when I bought my pop and it never cost me anything when I was done. Even free coffee and donuts both times

pkgmsu2000
08-24-2016, 05:09 PM
I got a couple free oil changes and shoe rotations back when I bought my pop and it never cost me anything when I was done. Even free coffee and donuts both times

my point is that service departments at dealerships dont respect other peoples cars. sure, free oil change, lol, but techs who just graduated high school forget to tighten things, they leave tools in your engine bay, they dont clean your interior after touching things with dirty greasy hands, they can cause from improperly lifting the car, damage driving the car or parking the car, some idiot gets too close and scratches the car up... and of course any damage they do is your word against theirs, you cant win that argument. something as simple as changing my oil is well worth it to me to get the car up on a lift, get under the car and do some quick inspections, look around the engine bay... always best to spot little problems that can fixed at low cost before they turn into big problems at high cost... changing my own oil isnt expensive and a great way to keep maintenance costs low and if i stay on top of things, i also feel safer and worry less.