[jarnie123]

My daughter recently purchased a used i30.
She says that at times (not often) it is hard to start and lacks power for a while and then comes good. She says that there does not seem to be a pattern to this problem and it doesn't happen often.
She took it to a mechanic (NOT a Hyundai workshop) and when she explained the problem he told her (my daughter's words) that he thinks it is a problem with the fuel rail and/or fuel pressure regulator and that it would cost about $500 to fix. I am not sure if she should pay out that sort of money unless she is assured that his diagnosis is correct. I know that there are many sensors in the engine such as the MAP, throttle position etc which could cause this problem.

Has anyone had that problem and if so what was the fix?
If not  does anyone have any ideas as to what they think the problem could be?

Thanks

[Dazzler]

Hi Jarnie,

I assume it is out of warranty?

I can see it is petrol but more information would help. What year and model. Series 1 (FD) or series 2 (GD)

Which motor? 2.0, 1.8, 1.6 litre?

[tw2005]

If you have an OBD2 scantool it may be worth doing a check for any codes . Crank sensor s have been known to play up. Next time it's hard to start, keep an eye on the tacho and see if it pulses at all on crank or totally dead.

Fuel rail / pressure regulator. SHould be an easy one to check the pressures but if it's intermittent I generally think electrical.  What's the history? how old, distance travelled, service history? Filters changed on time etc.

What gets replaced for $500? I'd want a detailed quote, also sounds like a guess, "He thinks"

[jarnie123]

Thanks everyone

My daughter tells me that it is a 2012 GD manual 1.8L with just over 100,000 kms.

I will ask her to check the tacho next time it is hard to start. I will ask her those other questions.

Thanks

John

[tw2005]

I believe the fuel filter is part of the pump in tank.  I know someone who's car would not start and that was after a filter replacement that broke something on the pump. It was dealer serviced, also read of poorly filter causing issues too, and if it has not been replaced at all, probably worth changing it out.

All my cars are CRDi (Diesel) so I can't comment first hand on any known issues.

@nzenigma

[jarnie123]

Some more information from my daughter -

It has always been regularly serviced ....
15000km Hyundai
32000km Hyundai
45000km Hyundai
60000km unsure
78000km Holden
90000 and 100000 by independent mechanic
"Mechanic He said he would replace the fuel pressure regulator as the pressure is showing to drop extremely quickly after engine switched off (He tested it)"  Any suggestions about this?

John

[tw2005]

Some more information from my daughter -

It has always been regularly serviced ....
15000km Hyundai
32000km Hyundai
45000km Hyundai
60000km unsure
78000km Holden
90000 and 100000 by independent mechanic
"Mechanic He said he would replace the fuel pressure regulator as the pressure is showing to drop extremely quickly after engine switched off (He tested it)"  Any suggestions about this?

John

I'd have to read up on it but manual says pressure should hold for 5 mins. If it drops quickly / immediately it suggests faulty check ball in fuel pump ( replace pump). If it's slow then suggests leaky injector or pressure regulator. Pressure spec is 46.9 - 52.6 psi

will have to read more tonight

Can't imagine $500 top replace a regulator though

[nzenigma]

About 50 psi is normal pressure for a fuel rail (petrol).

The regulator is in the tank and is attached to the pump.

Essentially, it does the obvious and sustains 50 psi, but also stops the pressure going higher. The latter is the possible fail point.

Havnt got an $au price for new, but  a 2nd hand pump would be about $100 and 20 minutes easy DIY to install under the back seat.

[jarnie123]

Thanks again everyone.

I have been in contact with my daughter (by email as she lives in northern Victoria and I live in Blue Mountains NSW) and this is what she said -

He replaced the pump a few months ago as that was his immediate guess (as well as the spark plugs).

I just msged him on messenger and he told me this:

Yes Mel. we attached a fuel pressure guage to the fuel pressure hose an ran the engine. While running the pressure was spot on but there was no dynamic response hen revving, ie the pressure should rise when revved. and also the pressure would drop after the engine was stopped. It should hold residual pressure when stopped.


Your comments? Is it correct what he said?

Also I checked Ebay for fuel regulators and found a genuine one listed at $129 and a non genuine one for around $60. Maybe his charge for the regulator would be higher as I can't understand why he has quoted her around $500 as from what you guys have said it is a fairly easy job and as such would it take more than an hour to replace?
I have suggested to my daughter that she ask the mechanic for an itemized quote.

[tw2005]

313803L100



AZERA 11- ELANTRA 12- i30 12- i40 11- GeNuiNe FUEL PRESSURE REGULATOR 313803L100 | eBay

[nzenigma]

'no dynamic response [w]hen revving, ie the pressure should rise when revved.'    yes, sort of.

it wont rise greatly if the regulator is working properly.

'He replaced the pump a few months ago as that was his immediate guess'

sensible move, but in doing so he replaced the attached regulator.

Therefore , pump, pressure and reg.failure solved??????

[tw2005]

'no dynamic response [w]hen revving, ie the pressure should rise when revved.'    yes, sort of.

it wont rise greatly if the regulator is working properly.

'He replaced the pump a few months ago as that was his immediate guess'

sensible move, but in doing so he replaced the attached regulator.

Therefore , pump, pressure and reg.failure solved??????

How do we know he replaced the whole pump assembly and not just the pump motor?

[nzenigma]

How do we know he replaced the whole pump assembly and not just the pump motor?

  In a world full of people joyfully lead by Trump, Boris and our Happy Clapper, who the *!!# would know what anyone thinks or does anymore? 

[jarnie123]

I called in to see my mechanic today and his first words were "nothing much goes wrong with Hyundai cars".
When I explained the problem he said that intermittent problems were almost impossible to track down and even Hyundai workshops might have problems even plugging their computer into the car.

His thoughts were that it could be the 'non return fuel valve' especially as the system does not retain pressure when the engine is switched off.
Where is the 'non return valve'? Is it supposed to be part of the fuel pump or regulator?

Thanks
John

[nzenigma]

Quick look to confirm> FD system is returnless.

GD is same pump reg set up so will also be returnless.

[tw2005]

I would expect it is integral in the pump motor as a spring loaded check ball. 

[nzenigma]

I would expect it is integral in the pump motor as a spring loaded check ball.

It is maintained by the fuel regulator.

I called in to see my mechanic today and his first words were "nothing much goes wrong with Hyundai cars".

He is correct.

 he said that intermittent problems were [time consuming and difficult]  to track down  correct


Where is the 'non return valve'? Is it supposed to be part of the fuel pump or regulator?   regulator

Thanks
John

John,  The story here is 3rd hand  and the way it is filtering through, I cant be sure if her mechanic actually changed both the pump and regulator , or just one part, or is he still just making suggestions.?????

As I said, you can get the whole unit from a wrecker and drop it in within 20 minutes. They are trouble free, so a used unit will be 99.9% ok.

Re fuel pressure; when the ignition is switched on the fuel pump relay closes for 2 seconds, you can hear that happen. The fuel pressure is now up to circa 50 psi. Relay cuts out. Engine can now fire up. Relay cuts back in and remains on. Fuel pressure is maintained. Engine keeps running. That seems to be happening.

If fuel pressure drops radically, there will be a loss of power. That may be happening.

I have had power and start problems on the FD with the purge valve. Hard starts straight after filling the tank with fuel is tell tale sign.

[jarnie123]

Thanks
I am getting all the info from my daughter and she seems to forget some things I am sure.
She reckons that her mechanic changed the fuel pump (and the spark plugs) and now is suggesting that replacing the fuel regulator would be the next step in fixing the problem. Why her mechanic didn't replace the regulator at the same time as the pump beats me. Maybe he was trying to save her some money - he may have thought that it was a faulty pump.

It seems from what I am now reading is that the non return valve is part of the regulator. Also that if my daughter waits a few seconds after turning the ignition on before starting then the hard starting may not happen - am I assuming correctly.
I have seen listings on EBAY of a GENUINE BRAND NEW FUEL PRESSURE REGULATOR SUIT HYUNDAI I30 1.6L,2.0L 2007 - 2012 FD GENUINE PART NUMBER - 313802H000 for $129 although the listing says for 1.6L and 2.0L and hers is a 1.8L I think. Hers is a 2012 model - it looks like a small metal can with a pipe bent at 90 degrees coming out of the bottom of the can and another fitting on the side of the can near the base.
Why her mechanic has suggested a charge (fitted) for around $500 beats me and so I have suggested to her that she asks for an itemized quote to find out how much he is charging for the part.

Once again thanks heaps.

[tw2005]

I already put part up for reg and link @$50 from korea in 2 weeks if you can wait

[nzenigma]

I already put part up for reg and link @$50 from korea in 2 weeks if you can wait

Mate, seems that you were correct to question the reg replacement.  I just assume people do the obvious or most practical.

The original story has holes in it. The pump was said to be achieving about 50psi, so the motor must start and drive. Why is it an intermittent start up?
The dynamic pressure fluctuation is not big if the regulator is functioning correctly. It seems to be doing that. The bleed off? Never measured it, cant comment on how long it takes.

$500 to go back in and replace the reg, right beside the already replaced pump, is a bit rich.  Would that make it a $1000 job (total) ????? 

[jarnie123]

Sorry missed the link. First time using this forum and didn't notice it.
I don't think my daughter would be bothered and in any case her brother works in the automotive industry and can get BOSCH brand items at trade price and will check next week.
Can I assume that BOSCH makes good regulators?

My daughter now tells me that since she has waits 2 or 3 seconds after turning on the ignition (before starting) the problem of hard to start has not occurred. I now assume from what you guys have suggested that since the pump was replaced that the regulator and especially the non return valve is faulty and she will look for a mechanic who will replace it at a reasonable cost.

[jarnie123]

Did someone earlier suggest that a possible cause could be a leaking injector?
I can imagine that would also cause the pressure to drop quickly after turning off the engine BUT wouldn't there be other problems if an injector is leaking such as rough running?
Thanks

[chaddyhyundai]

Have you tried to switch off 'Eco' mode?  Eco mode makes the i30 drive in grandfatherly fashion, but without it the i30 should be a much more willing performer.  On the 'intermittently hard to start' I have had that as well about 4 times in the last 2 months, mostly for warm starts, but Hyundai has been unable to replicate it.

[CraigB]

Have you tried to switch off 'Eco' mode?  Eco mode makes the i30 drive in grandfatherly fashion, but without it the i30 should be a much more willing performer.

Eco mode on a manual GD does little more than suggest economical shift changes, turning off on your auto holds gear slightly longer.