[milto93]

Hi,

I've been having some trouble with my 2011 i30 as of late. When the engine is cold it takes up to 5-6 goes to start, it started off as a rough start and has been getting progressively worse over the last couple of months. If I start the engine again after a few hours (so its not fully cold) there is no issue, and while driving there is no problems. Only has trouble when i start it in the morning or after being at work. I've included a video, i only started recording after a few attempts at starting it.



The car has has been into Hyundai and no fault codes came up, while it was there the latest software update was completed. I've also changed the Fuel filter, fuel pump, cleaned the IAC and throttle body and switched the fuel pump relay around (swapped with the horn). None of these seem to have helped.

[Dazzler]

Welcome milto,

These hard to diagnose problems can be so frustrating! You have certainly made some logical efforts to sort it. My wife had a 2.0 Petrol CW (2010 build / MY 11 model) which had an issue with starting but only a couple of times and we suspected the immobilizer coil in the ignition was to blame. It came right by itself - no fault found at dealer (as usual)

We are very lucky to have 3 very good honorary Technical Advisors and several other unofficial mechanical gurus on the site. Hopefully they can come up with some suggestions. As you are no doubt aware it is very hard to diagnose these things by remote control (so to speak) Please be patient for replies as we are a worldwide site so it takes a while for everyone to view new postings.

@cruiserfied @nzenigma @tw2005 @diesel1984

[nzenigma]

Hi Milto,
Dazz has said it all . Hard to identify a problem. The single short start then fail, that you filmed would have me looking at a fuel problem, so you have been doing all the right things.
The EVAP purge valve used on many Hyundai  can cause this sort of problem, especially when you have just filled up with fuel. Usually you will have a code.
Irrespective, Ive found many leaking , so don't ignore it. Back of motor- top left side.

[milto93]

Thanks guys, yeah I know problems like this can be pretty frustrating.

So today I used my spare key to see if maybe that could eliminate the immobiliser as the issue, it didn't seem to help. However I tried cycling the key from ACC to ON a number of times before attempting to start it. After that is started no worries. I haven't had a chance to check the EVAP purge valve yet, but I will shortly

[Dazzler]

The spare key won't necessarily eliminate the immobiliser as the issue it could be at the coil in the ignition rather than the chip in the key. The fact cycling the key helps may point to the immobiliser,  I'm not sure though.

[nzenigma]

If it is immobiliser you wont get the engine to fire at all. No rough running etc.
Instead of switching AC to On multiple times; try just switching ON then wait 60 secs before starting. Does that work?

[cruiserfied]

Did this problem start after a fuel filter change?
I know you said you have changed the filter since it happened. But it hadn't recently had a 60000km service?
It sounds very much like a pinched or missing o-ring on the pump or pressure reg.

Didn't say it before because you said the fuel filter and pump have been replaced, but after you said it started well after cycling the key several times. That would have primed the fuel system.

Just a thought.

[nzenigma]

as he said

[milto93]

Cheers, appreciate the help! Turned it over this morning, no luck, turned in off then left it sit at ON for 60 seconds before trying again and it started.

As for the fuel filter, it was very old and brown when I pulled it out so I doubt it had just been changed. I also forgot one of the o-rings and had to pull it out again to fit it. It wouldn't start at all without the o-ring on top of the pump. And the problem was present before I started playing around with the pump assembly.

I also took note of the immobiliser light on the dash and it goes off when cranking and doesn't do any weird flashes.

[cruiserfied]

Yeah missing o-rings happens to the best of us. How many km's when it started/filter change/now?

It still sounds alot like it is slowly loosing fuel prime. The pump should run for about 3-4sec after ignition on. There may be a problem with your pressure regulator or injectors leaking.

It might take a few days but i would like to know what happens if everytime you start the car do this,

-Key to ON position
-Count to 5
-Key OFF then back to ON
-Count to 5
-Start

If there is a fuel prime concern it should start ever time doing this.

[nzenigma]

  what she said again

A slow count to 5 can take 60 seconds

[fifthwheel]

Not very likely to be the issue, but have you checked the 80 amp glow plug fusible link? I was getting rough starts with a cold engine until it stopped needing to be replaced.

I only suggest it because it's a very easy thing to check and (mostly) easy to replace.

EDIT: most certainly not the issue when you run on petrol. 

[milto93]

The rough starts have been an issue for about 5000km (always started first go, just didn't feel 100%), then about 2000km ago it started taking a couple of goes. After this I changed the fuel filter, didn't fix it and it progressively got worse still. I then changed the fuel pump about 300km ago.

I was also thinking that it loses fuel pressure over time rather than it being engine temp related. Thought it might be the fuel pump not holding pressure, hence why I changed it. You mentioned that injectors or fuel pressure reg could also cause a loss of pressure? Any easy was to check them?

I also tried two key cycles this morning, it wasnt enough. Might have to try 5-6 tomorrow. Here's a video of this morning's start.

[nzenigma]

I will leave Tim to follow up on his advice. Its all good stuff.
As I said above it seems that you have been making all the right moves especially that we have more info on the history.
The fuel regulator is questionable, so did you fit a brand new fuel pump assembly or was it ex-wrecker?
Just a thought that you were unlucky with the second one.

[milto93]

The filter was a genuine part and the pump was a Bosch replacement part. The actually assembly is still the original one, I've just changed those two bits within it

[nzenigma]

Cool thanks, over to Tim @cruiserfied

[cruiserfied]

Hmm good video. Too bad it didn't get you anywhere though.

Any next step i would consider is starting to get a bit deeper into diag.
I would be pulling the sender out to inspect and put a fuel gauge on it to see pressure when problem is happening. Maybe send the injectors out for testing.

Of course without having the vehicle in front of me to experience it first hand im clutching at straws.