Kia Forte Turbo Forum banner
1 - 20 of 28 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter · #1 ·
Don't really know how to explain this but ill try the best I can so when I'm driving at like 40-50 and sometimes from a stop I will go to step on the gas and it will be lazy not turbo lag lazy but like will feel like its struggling to get up to speed and then other times it will feel fine and nothings wrong when I coast at those speeds or just lightly tap the accelerator at those speeds it also feels like there's a very faint shimmer feel where it feels like im gonna let the clutch out from a stop (but at like 40-50 mphs) its very faint and only happens for like a sec then everything kicks on more of an annoyance right now then a true problem maybe. anyone got an ideas on what this could be? maybe im just losing it.
 

·
Registered
Joined
·
458 Posts
Are you going WOT and where is the RPM when you're calling for power? Personally, I don't feel like this car has any go below 3,000RPM and it's advised that we don't go WOT below 3,000-3,500RPM anyway so that's where I cruise at in the city. It's in case I need to avoid any bonehead who cuts me off or I need to do sudden lane changes from situations like that. Terrible for gas mileage but it's cheaper than being t-boned or worse.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #3 ·
What is WOT? One time the RPMS where lower and it was very lazy through all of first and most of 2nd up to like 45-50 and the rough shaking studdering seems to happen when I very lightly put on the gas in like 3-5 gears at lower rpms between 45-70 ill have like cruise on and ill just love tap the gas very lightly and it will feel like I'm about to bog out very faintly the car will like shake.
 

·
Registered
Joined
·
1,697 Posts
From your intro it looks like the car may have about 24k miles.
There are things that may need to be addressed.

One of them are air leaks (should not really matter as engine depends on actual boost pressure) as they may cause weird issues. That means check tightness of all clamps before and after compressor (turbo).
Then - fuel.
It may be poor fuel quality and poor delivery.
Some cars suffered from kinked fuel hoses causing poor power. If I recall, there was one member who has high pressure pump replaced as well. High pressure as you get fuel dumped into cylinders at 2500 psi, while MPI engines get the pressure rather about 50 psi.
As for poor quality - well, add some better grade, say 89/91 octane.
However, running 91 or 93 octane may sometimes cause problems as well (poor combustion efficiency - simply it is too resistant to ignition). But for this to happen you would need to have more issues such as bad spark plugs, weak coils...
And at this point we get to spark plugs.
2015 MY had the older type of spark plug. Unless yours was updated.
Older means at hotter temperature. That means the spark plug was running hotter than should be, causing issues as you describe.

Being 2015 (registered when? dec 2014 at the earliest?) and 25k miles - still warranty. I guess reporting it to your dealer can get some things done or checked.

There is one more thing, but this would rather be happening every time. It is the dog bone engine mount. MT are much more prone to having them worn due to shifts (load changes).
You may want to replace the rubbers there if you experience wheel hop. Just be advised - it may increase vibrations in the car.


Besides the above - when I was driving 2015 F5 MT I loved the low end torque. Do not get me wrong, the current 2016 AT has same, but in MT it was better. I never complained about poor power at low rpm (low rpm means about 2000-2500). Sure, it was pulling like crazy past 3500 and seemed like a beast when pushed closer to 5500, but only after slow driving (it was simply feeling of the power rush).

Let us know what you discovered and how the problem was addressed.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #6 ·
Any advice for what type of spark plugs should be used? I'm gonna have my guy look at these issues and see if they are the problem! thank you! any advice for rough shifts into gear it feels like it grinds sometimes when shifting into gears and other times its really smooth
 

·
Registered
Joined
·
458 Posts
WOT (wide open throttle) don't floor it at low engine speed, when I need power I run the engine between 3 & 5.5k under that it struggles.
At any RPM this car must feel slow compared to your V6.

Drove a GTX Grand Prix back in the day. That thing was a beast.
 

·
Registered
Joined
·
1,697 Posts
Any advice for what type of spark plugs should be used?
Pull out at least one of yours and note the model you have. We can go from there.

At any RPM this car must feel slow compared to your V6.
Not every V6 is same. You can have 1.8 V6 in Mazda MX-3 or 4.3 in Chevy S10.

I would say, at low rpm Forte must be quicker than any "normal" NA V6. In 4th gear, at 2000 rpm - GP would not pull the same. WOT or not.

any advice for rough shifts into gear it feels like it grinds sometimes when shifting into gears and other times its really smooth
At 25k miles one may check the gear oil.
I was surprised how smooth this tranny was comparing to 2009 Hyundai Elantra. That one did not like cold shifts at all.
So, for Forte - just to cover basics - make sure clutch is completely depressed. This one catches very early low, so I even caught myself not to pushing it all the way down. It was OK to move out of gear, but not enough to move in.

As for gear oil - Redline is good. I got Elantra to have very smooth shifts with this oil. Did not cure everything, but was much better.
 

·
Registered
Joined
·
458 Posts
Pull out at least one of yours and note the model you have. We can go from there.



Not every V6 is same. You can have 1.8 V6 in Mazda MX-3 or 4.3 in Chevy S10.

I would say, at low rpm Forte must be quicker than any "normal" NA V6. In 4th gear, at 2000 rpm - GP would not pull the same. WOT or not.



At 25k miles one may check the gear oil.
I was surprised how smooth this tranny was comparing to 2009 Hyundai Elantra. That one did not like cold shifts at all.
So, for Forte - just to cover basics - make sure clutch is completely depressed. This one catches very early low, so I even caught myself not to pushing it all the way down. It was OK to move out of gear, but not enough to move in.

As for gear oil - Redline is good. I got Elantra to have very smooth shifts with this oil. Did not cure everything, but was much better.
Funny you mentioned the MX-3 because my older brother owned one when it came out. It was called the Precedia, lolwut? It had pretty good get-up from the butt dyno but I was too young at the time to know better.

Again, I think my recollection of years past may be skewed comparing to modern day experiences but all I know is the big displacement V6s were such a riot. Never driven a V8 before; that and the V12s is kind of on my bucket list.


Regarding the application specific oils, does it really make a difference? Will Motul or Royal Purple really be better than say, Castrol or Quaker State? I heard of Redline, but how tangible are these premium oils compared to regular stuff?
 

·
Registered
Joined
·
827 Posts
20 Regarding the application specific oils said:
The motor oil AND filter make an enormous difference. YOu can perform an empirical & Scientific test yourself. Go buy one of those hideous orange FRAM filters and some gawd-awful Kmart grade budget oil. Run the oil for 5000 miles and have the oil & filter analyzed. Do the same thing with Mobil 1 and a mobil 1 filter. Then you'll know.
Otherwise you're a victim of marketing hype and circular debates.
 

·
Registered
Joined
·
1,697 Posts
Again, I think my recollection of years past may be skewed comparing to modern day experiences but all I know is the big displacement V6s were such a riot. Never driven a V8 before; that and the V12s is kind of on my bucket list.
I would turn to the old cars where engine was not limited by computers and was making power the way you would set up carburetor or adjust timing.
I brought up 1.8 V6 as a comparison as saying V6 is better than I4 may not be true. 1.8 V6 will be weaker than 2.5 I4 at any given point. Sure, V6 will rev easier due to +2 cylinders and being lighter per piston. But that's it...
I also recall my 1991 Trabant (1.1 version) seemed faster than 1997 Neon (DOHC version) I had as the first car in the US.
How come 1.1 I4 be better than 2.0 I4? No clue... and it was not. It was the computer and transmission. Trabant was stick. Neon was AT... and it was heat soak as much as it can get. It was awesome on cold, but once temperature got it, power was killed. Intake was sitting on the head. Nice and hot.


Regarding the application specific oils, does it really make a difference? Will Motul or Royal Purple really be better than say, Castrol or Quaker State? I heard of Redline, but how tangible are these premium oils compared to regular stuff?
The motor oil AND filter make an enormous difference. YOu can perform an empirical & Scientific test yourself. Go buy one of those hideous orange FRAM filters and some gawd-awful Kmart grade budget oil. Run the oil for 5000 miles and have the oil & filter analyzed. Do the same thing with Mobil 1 and a mobil 1 filter. Then you'll know.
Otherwise you're a victim of marketing hype and circular debates.
I think it was referring to gear oil, not engine oil.
However, NOPE, no way I am trying that. I stick to OEM filters - period. As for oil. Oil is just oil. For everyday drive, in "regular car", you would not see a difference. As long as lubricant is there - it works. The only difference could be seen in cold start and then some small in overall fuel consumption, which actually mainly depends on your right foot - how you accelerate and mainly how you coast.

I said Redline only because that is the only manufacturer that makes 75W85 GL-4 oil as synthetic. Or go OEM...
Yet with those cars gear oil wears down faster due to power.
I did see big change, mainly in very cold and very hot (not much between though) in Elantra. Never got to change oil in MT F5.
 

·
Registered
Joined
·
827 Posts
I would turn to the old cars where engine was not limited by computers and was making power the way you would set up carburetor or adjust timing.
I brought up 1.8 V6 as a comparison as saying V6 is better than I4 may not be true. 1.8 V6 will be weaker than 2.5 I4 at any given point. Sure, V6 will rev easier due to +2 cylinders and being lighter per piston. But that's it...
I also recall my 1991 Trabant (1.1 version) seemed faster than 1997 Neon (DOHC version) I had as the first car in the US.
How come 1.1 I4 be better than 2.0 I4? No clue... and it was not. It was the computer and transmission. Trabant was stick. Neon was AT... and it was heat soak as much as it can get. It was awesome on cold, but once temperature got it, power was killed. Intake was sitting on the head. Nice and hot.






I think it was referring to gear oil, not engine oil.
However, NOPE, no way I am trying that. I stick to OEM filters - period. As for oil. Oil is just oil. For everyday drive, in "regular car", you would not see a difference. As long as lubricant is there - it works. The only difference could be seen in cold start and then some small in overall fuel consumption, which actually mainly depends on your right foot - how you accelerate and mainly how you coast.

I said Redline only because that is the only manufacturer that makes 75W85 GL-4 oil as synthetic. Or go OEM...
Yet with those cars gear oil wears down faster due to power.
I did see big change, mainly in very cold and very hot (not much between though) in Elantra. Never got to change oil in MT F5.
PLP - I'm virtually CERTAIN you wouldn't try that test I suggested.
And I have no doubt that your personal logic is stated in the generalizaton right here (exact quote) "As for oil. Oil is just oil. " I'm certain that is your viewpoint.
Great to live a free country!
 

·
Registered
Joined
·
1,697 Posts
And I have no doubt that your personal logic is stated in the generalizaton right here (exact quote) "As for oil. Oil is just oil. " I'm certain that is your viewpoint.
That is only a part of my sentence. It is taken out of context. :)
You missed the part "for regular daily driver". Say you just go from point A to point B using, say Chevy Aveo (whatever car) that you just drive. Then having a 5W-20 from Sears or same viscosity from Purple - you would not even know except the price.
So do not misrepresent my statements lol
JK
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #14 ·
An update on my car as of 9/21/17Hey guys so we changed out the spark plugs and oil in my car and I thought everything was going good but I noticed today when I tried to pass someone going about 45 I dropped down into 4th and went WOT and the car begain to sputter out its almost like its clogged or something there was no power it was trying to go forward you could feel it attempting to throw power forward the car would like lurch forward a few times then it gained a little power and seemed fine but it was almost like I was in to high of a gear kinda feel or feel like when your coming to a stop in a high gear its that kind of sputter. any ideas? sorry I'm really bad at explaining things lol
 

·
Registered
Joined
·
19 Posts
search for the Fuel line issue and see if that sounds like your situation.
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #16 ·
from what I'm reading the only issue I have in common is loss of acceleration when I step on the gas and it only happens sometimes its the weirdest thing took it to kia and they told me nothing was wrong I cant be going crazy can I lol
 

·
Registered
Joined
·
1,697 Posts
search for the Fuel line issue and see if that sounds like your situation.
It is not fuel issue.
It is rather boost or more likely ignition related.

An update on my car as of 9/21/17Hey guys so we changed out the spark plugs and oil in my car and I thought everything was going good but I noticed today when I tried to pass someone going about 45 I dropped down into 4th and went WOT and the car begain to sputter out its almost like its clogged or something there was no power it was trying to go forward you could feel it attempting to throw power forward the car would like lurch forward a few times then it gained a little power and seemed fine but it was almost like I was in to high of a gear kinda feel or feel like when your coming to a stop in a high gear its that kind of sputter. any ideas? sorry I'm really bad at explaining things lol
I know what you are talking about.
Exactly same is happening to mine. On very rare occasions it seems like power is gone. It pulls, but very slowly, like a weak engine.
My boost gauge shows no more than 5-7 psi at that time. Sometimes, just before that happens, I have a quite loud ping.
One more thing happening moments before - kind of uneven power, sometimes overboost (I got 21 psi or even more as gauge went out of scale and the needle was shaking between 20 and 25 psi), ping like noises, and smoke. Lots of smoke.

To me looked like carbon deposits or something causing spark plugs to get too hot and not allowing much of power due to preignition.
Another one could be poor gas. But it would happen once per tank. Then I could not duplicate it.


One thing solved the problem for a while in my previous car - putting colder spark plugs. I put XP 5702 and the car had so much power. It pulled like crazy everytime. Until the spark failed within about 1000 miles. Never put them back again. Returned.


When I was testing 89 and 93 octane petrol I did not really have this issue coming back.
Yet, it would not mean it would or would not present itself.

It happens only when you have been driving for a while and engine is hot. It may or may not be preceded by ping.
It is not fuel starvation issue, as it is not constant. I can pull over, put in parking, rev, drop gear and still nothing. Then I restart the engine and all is fine...
 

·
Registered
Joined
·
11 Posts
Discussion Starter · #18 ·
ya that's exactly whats happening I think ive even heard the loud ping before and wondered what the hell it was I have xp5702s in there right now I believe and I'm using BP 91 octane which is really the only gas I have in town except at a crappy kwik trip. so you think its spark plugs or something more or something else I'm so confused on why this is happening and its frustrating the shit outta me!
 

·
Registered
Joined
·
1,697 Posts
Hmm...
your statement confuses me then.
Having XP5702 (if there are not damaged, I do not see why they would cause any problem - I had ceramic drop) should be all good. Mine are OEM heat so I thought it was that.
That seems like something else then.

I will think of it what else I should go after.
If yours is 91 octane and +1 heat range - darn it, that makes it a completely different beast then.

What year it is? How many miles? Production date? Any mods, tune, and such...
You did not say about your ride when you joined...



For me it was actually two different scenarios.
One with the ping, then overboost, smoke, and power drop.
Second was after driving on highway (regular, gentle speed, nothing fancy) and when I come to accelerate at 60 mph - nothing is happening. It upshifts, revs, and no power. But this one is "quiet" without any initial problems.

Again, give me some time... :) I might come back with something.
Or maybe someone else will drop some idea.

But this exact problem happened to me a few times: in 2015 F5 MT - at about 15k miles, then 17k, and near 19k. In 2016 F5 AT: 5k, 8k.
But I would almost always put 87. For a while had 89 and 93 (about 1600 miles, exactly 6 tanks). Car was going same.
No really any mods. Testing intake to make any difference for power/noise/fuel consumption.

So far I can tell it makes a bit more power, but definitely uses more fuel. Just off topic...
 

·
Registered
Joined
·
534 Posts
Ok, first let's get some data logs in here. An obdii reader and some software are cheap enough and valuable enough to have. We are grasping at straws here trying to speculate.


There are 3 things and engine needs, fuel, air and spark. So at a minute we need to get information on boost, fuel pressure and timing. Then we can move forward.

But to speculate, this could be a bad coil, more boost due to a bad sensor, fuel pressure cutting out etc.
 
1 - 20 of 28 Posts
Top