[joesama]

Hi guys.
Just need some perspectives on what might be the issue with this i30 I have in the household at the moment.
As you all know the model I have is 2013 i30GD 1.8L hatchback.

Last year Nov, I went ahead and did the servicing of the vehicle.

8th year service and I followed the service schedule and did the following.

-Engine oil and filter replaced.
-Coolant fluid replaced after several runs of demineralised water until on the 4th drain, no more colour left.
-Replaced in tank fuel filter.

All parts and fluid are Genuine Hyundai parts. Even the coolant.

Following the change of all the above, I started to feel slight engine hiccups at cold start once the vehicle was stationary until cold. It gets worst when A/C is turned on.
This hiccup disappears once engine is warmed up.

So to try to get this fixed, I have done the following.

Used Moly Poly Fuel system and injector cleaner. No change.
Replaced the fuel filter with another new genuine fuel filter. No change.
Replaced the entire fuel pump with a new fuel filter. No change.
Replaced the Spark plugs. No change.
Cleaned the MAF sensors. No change.
Cleaned the Throttle body. No change.
Cleaned the fuel injectors. No change.

Checked the air filter, they are clean.
I also don't see any leakage of fuel any where.

The vehicle also do not overheat.. the temp rises to just below halfway point and stays there at all times.
(This rules out air pockets in the coolant system?)

And the worst of all, there is absolutely no code in OBD scanner. Ugh...

So.. I'm at loss at the moment as what is the problem.

Any suggestions what might be the problem?

[Aye30]

hi, I have a 2.0l so don't know the 1.8, but when cleaning the throttle, was the iac - idle air control valve cleaned out? (if fitted)

[joesama]

So I don't think this 1.8 GD have Idle control valve..

But is there a bleeder for coolant? I have a feeling air is trapped in the throttle body.

[joesama]

Hi guys..
Im still facing the issue..
So far, I have changed more things to see if that helps.

Replaced Both Cam shaft position sensors.
Replaced Crank shaft position sensor.
Replaced Coolant again.. And also bleeded it while at it.

No change what so ever.
The strangest thing is that it never happens once the car is warmed up.
Only from the initial cold start until about 5 to 10mins. It surges.
Ill try to make a vid out of it when I can.

Any ideas guys?? Im at loss at the moment. Very disappointing.

I've also called up a fuel injector cleaning shop and told the guy about the symptoms and he said.. does not sound like injector issues at all.

[joesama]

So I've received brand new plug coils today and fitted them.
There are no symptoms of hiccups anymore at the moment. Looks like its fixed. Will report back in a next few days after testing the car.