[Hyundai i30 1.4]

Hello guys, I’ve just bought a Hyundai i30 model year 2016. It’s a 1.4 petrol engine, type g4lc and I have a problem with the oil pressure, hope you can give me some advices. It first happen when the engine was warm, when I started the car the engine oil light came up so I checked the oil level and it was ok, I towed the car to a shop and they changed the oil pressure sensor and checked the oil pressure and it was all fine. After I drove like 20 km and shut down the engine and restarted after 10 minutes the oil light came up again. I checked the oil pressure again and it is low. I mention that the engine was changed by the dealer when the car was in warranty and it currently has about 65.000 km.                                      Does anyone encountered this issue and have any ideas of how to solve it? Thanks!

[TerryT]

...After I drove like 20 km and shut down the engine and restarted after 10 minutes the oil light came up again. I checked the oil pressure again and it is low....

Just to clarify something which has confused me a little (which is not too hard these days) and it may help our technical guys understand the problem. 

When you say, "I checked the oil pressure again and it is low", do you mean you used an oil pressure gauge to measure the oil pressure or you meant that the engine oil in the sump/oil pan was low on the dipstick?

As your oil pressure sensor is new it would normally rule that part as being the problem.  One issue could be faulty/damaged wiring somewhere from the sensor to the dash (or a faulty oil dash light?) but electrics are the Prince of Darkness to me, unfortunately.

[Hyundai i30 1.4]

Yes, the oil pressure was measured with an oil pressure gauge.

[TerryT]

Ok, thanks for the quick reply.

So, the workshop “...checked the oil pressure and it was all fine[/b].”  Did they tell you what the oil pressure reading was at idle and say, at xyz rpm?

You said: “After I drove like 20 km and shut down the engine and restarted after 10 minutes the oil light came up again.  I checked the oil pressure again and it is low.”  So, what oil pressure readings did you see on your gauge at idle and say, at xyz rpm?

[TerryT]

@ Hyundai i30 1.4

Now I know that you used an oil pressure gauge to test the oil pressure, you can forget everything I said about the oil sensor wiring possibly being faulty. 

[Hyundai i30 1.4]

First time they checked the oil pressure they said it was about 1.8 BAR, then the oil, oil filter and oil pressure sensor was changed, I drove the car and after the engine got warm, the oil light came up, so I checked the oil pressure, at idle was 0.4 BAR which is about 6 PSI and it got higher when accelerating, at 1000 rpm it was close to 1.8 BAR but when let to idle the oil pressure dropped to 0.4 again.  The oil used is 5w30 as recommended by the carmaker.

[Greyhound]

What rpm is the engine idling at?

[Hyundai i30 1.4]

The engine is idling at about 750 rpm

[Greyhound]

As your oil pressure is normal 1.8bar at 1000rpm but only 0.4bar at 750rpm I was thinking your idle spreed was low.
I found this post where idle speed (1.4L Petrol) was discussed. There idle rpm mentioned is higher than yours.
1.6 diesel - Idle speed, how noisey at idle and air con whine

Maybe others with the 1.4L Petrol can post the idle rpm they have. 

[PGN I30]

How often has the oil been changed and with what oil?

[Hyundai i30 1.4]

I don’t know what to say about the idle rpm, everything seems to be ok. And for the oil, the previous owner said he changed it every 10k km, he used the 5w30 I think

[TerryT]

@ Hyundai i30 1.4
Your problem has bugged me, mainly because imo you have done everything right but are still no closer to an answer. 
You need one of our tech guys to weigh in with some knowledge or experience with this type of problem.
I had started scribbling down some notes to consolidate all the info in the posts here and before I knew it, I had a novel, but I'm a persistent bugger (my wife says it's one of my endearing traits!).

Car:
•  2016 i30, 1.4 petrol engine, type G4LC with approx 65,000 km (odometer?). 
•  Engine changed by dealer when car was in warranty 

History of problem
- Started the car with a warm engine, engine oil light came on.  Checked oil level, it was ok.
- Towed car to workshop.  They changed the oil (5W30, as rec’d by Hyundai), the oil filter and the oil pressure sensor. 
- Workshop checked the oil pressure and said it was all fine @ 26 psi (rpm not stated).
- You drove car for approx. 20 km, stopped it and restarted it, and after 10 minutes the oil light came on. 
- You checked the oil pressure with a gauge and it was 6 psi at idle (750 rpm) and 26 psi (1,000 rpm). 

Previous car owner says the engine oil was changed every 10,000 km with 5W30 (and presumably the oil filter was changed regularly) so that would normally rule out old, contaminated engine oil gumming up passageways and parts etc.

Troubleshooting: Causes of oil pressure light coming on and/or low oil pressure:
1.   Faulty oil pressure sensor
2.   Faulty oil pressure sensor wiring
3.   Oil level too low
4.   Incorrect engine oil viscosity
5.   Clogged or dirty oil filter
6.   Engine wear
7.   Restricted oil pickup
8.   Oil pump failure

The work done by your workshop, yourself and previous owner has basically ruled out items 1~5.  Given the age of your engine and the previous owner’s maintenance regime, that would likely rule out items 6 & 7. 
So, I’m going for item 8, faulty oil pump…only because I’ve run out of everything else. 😊

Questions:
1.  Have you noticed any decrease in the engine’s power; or the engine temperature gauge has been a little higher than normal? 
2.  Is the engine a bit noisier (especially from the valve train and the oil pump areas?).
3.  How long have you owned the car?
4.  How many kilometres has the new engine done (not what's on the car's odometer).
 

[PGN I30]

I do wonder why it had an engine change during the warranty period and did the previous owner actually look after the engine, as said, it could be a blocked oil pickup in the sump or a faulty oil pump. Dropping the sump to inspect the oil pick up would be the first thing to look at, the oil pump replacement is a bit of a job.

[eye30]

As your oil pressure is normal 1.8bar at 1000rpm but only 0.4bar at 750rpm I was thinking your idle spreed was low.
I found this post where idle speed (1.4L Petrol) was discussed. There idle rpm mentioned is higher than yours.
1.6 diesel - Idle speed, how noisey at idle and air con whine

Maybe others with the 1.4L Petrol can post the idle rpm they have. 

700rpm

[TerryT]

the engine was changed by the dealer when the car was in warranty

@ 567 I30.  Thanks for your input.  I too wondered about the significance of the engine swap and had made the following assumptions:
1.  The "dealer" was a Hyundai dealership, so...
2.  The engine fitted would be brand new, so...
3.  Would have a new oil pickup fitted, and...
4.  Would have a new oil pump fitted.

IF items 2~4 are correct, you would think that would rule out a faulty pickup and/or faulty oil pump especially IF the new engine had been serviced according to the owner's manual. 

And, when/if Hyundai i30 1.4 answers my questions #3 & #4 in my post above, it should help us better understand things. 

D'oh!! I should have also asked Hyundai i30 1.4  what kilometres were on the odometer when he bought the car secondhand as the problem happened at around 65,000 kms.  That would tell us how many kilometres he drove the car before the problem surfaced. I also should have asked him if the previous owner said why the original engine had to be replaced!

While the oil pump shown below is from an Elantra i30 Tucson 1.8/2.0 it shows where the oil pump fits in the engine for those that didn't know.

[Hyundai i30 1.4]

First of all, I just want to thank you guys for trying to help me with this! And to answer your questions, I only own the car for less than a month, so I drove it for about 300 km. I did checked the cars service history at a Hyundai dealership and they told me that the car got a new engine at 110k km (odometer). So I asked the previous owner why the engine was changed, he replied me that it started “knocking”
The car s odometer shows now 173k km so the new engine should have ~63k km. the previous owner also told me that the engine was changed at a Hyundai dealership. I took the car to a different mechanic now, he also asked me about the same question you guys did, he started the car to hear the engine, at first it sounded normal, after a bit of time, with the oil light on in the dashboard, the engine sound changed, it started to knock. The knock seems to be from the left side of the engine, from the timing chain cover. They said they ll check the sump and if nothing is wrong there they’ll take down the oil pump.
I hope I answered your question. I’ll keep you posted.

[Aye30]

Oil pressure adds extra tension to a timing chain tensioner. Is this belt or chain. My 1.4l i20 was chain and older oil would cause noise under the timing chain cover. I never had the oil light come on though. If the oil inlet oring on the timing cover was not being 100% effective, would it struggle againt the thicker warm oil and potentialy allow more air to be sucked into the oil pump? New, cold oil at 5w is thin, and easily drawn into the pump. ( Not  A Mechanic, Just someone reading along ) At roughly 63K the oring should not be an issue, but the cover is sealed with a liquid gastket around the perimeter, and then torqued to spec, if , and a very big if too much liquid gasket and  slightly under torqued bolts, a new oring may have been able to hold back the air leak, but as it aged it may not have been able to keep up.

[TerryT]

@ Hyundai i30 1.4. 
In light of the helpful information in your last post I have amended my summary of your 'Car' and 'History of problem'.  (All figures have been rounded off for convenience).

Car:
- 2016 i30, 1.4 petrol engine, type G4LC.
- New engine was installed under warranty by Hyundai dealership at 110,000 km.
- Car’s odometer is now 173,000 km, so the new engine has done only 63,000 km.
- You have owned the car for less than one month and have done only 300 km in it.
- Previous owner says the engine was replaced because it had started “knocking”.
- Previous owner says engine oil was changed every 10,000 km (5W30)...and presumably engine oil filter was changed regularly?).

History of problem
- Started the car with a warm engine and engine oil light came on.  Checked oil level, it was ok.
- Towed car to workshop.  They changed the oil (5W30), the oil filter and the oil pressure sensor.
- Workshop checked the oil pressure and said it was all fine @ 26 psi (rpm not stated).
- You drove car for 20 km, stopped it, restarted it and after 10 minutes the oil light came on.
- You checked the oil pressure with a gauge and it was only 6 psi at idle (750 rpm) and 26 psi @ 1,000 rpm.

You said the mechanic recently started the engine and "...after a bit of time, with the oil light on in the dashboard, the engine sound changed, it started to knock."  So, the oem engine had "knocking" problems and the replacement engine after 63,000 km is "knocking".  That is nastily weird! 

You said in your last post that your workshop will now check the sump and if nothing is wrong there they’ll take down the oil pump.  That sounds encouraging.  (I’ll take the money if it turns out to be say, an oil pump faulty pressure relief valve. 😊).

Yes, please keep us posted.

[TerryT]

@ Hyundai i30 1.4.  Mate, in your last post (26 March) you mentioned that your  "...workshop will now check the sump and if nothing is wrong there they’ll take down the oil pump."

Anything new to report?  It had a few of us here thinking. 

[Hyundai i30 1.4]

Hello, the problem isn’t solved yet. They checked the oil sump but nothing was wrong with it. I ordered a new oil pump but something happened with the transporter, so it didn’t arrive yet. I’m waiting for the order to be shipped and then to install the new oil pump. I really hope this will fix the problem.

[TerryT]

Hello, the problem isn’t solved yet. They checked the oil sump but nothing was wrong with it. I ordered a new oil pump but something happened with the transporter, so it didn’t arrive yet. I’m waiting for the order to be shipped and then to install the new oil pump. I really hope this will fix the problem.

Thanks for the update.  This is becoming a long trek for you.  Hope they strip down the old pump and find a fault with it.  My wife and I spun the wheel and we are going for a faulty pressure relief valve.

[TerryT]

Hello, the problem isn’t solved yet. They checked the oil sump but nothing was wrong with it. I ordered a new oil pump but something happened with the transporter, so it didn’t arrive yet. I’m waiting for the order to be shipped and then to install the new oil pump. I really hope this will fix the problem.

Thanks for the update.  This is becoming a long trek for you.  Hope they strip down the old pump and find a fault with it.  My wife and I spun the wheel and we are going for a faulty pressure relief valve.

@ Hyundai i30 1.4.  Hi, have you now found out the reason for your low oil pressure?

[schmick325]

I am battling this in a 2014 IX35 2.0 Petrol G4NC. The car had an intake cam timing code, so installed a new intake VVT solenoid and a new timing chain, tensioner and guides. Still no fix. The timing was ok as well before I changed the chain/guides.

I noticed the oil seals for the pump were flat, so changed those. No change.

Installed a new intake cam sprocket. This fixed the cam timing issue. All this and my 3rd time taking the engine apart, it now has chain rattle on a cold start.

I wish I had now dismantled that oil pump, inc the pressure relief valve and inspected it for sludge or worn components. Aside from a blocked oil gallery leading to the tensioner or worn main bearings, that's all it can be. Engine makes no bad noises at all.

I found a good YT vid of how the pump works. Even though its based on a Toyota, it is the same as the oil pump used on these cars How the Engine Lubrication System Works - YouTube

You can see on the oil pump where the old chain was striking it

[schmick325]

Interesting, have noticed in this photo there appears to be hairline cracks in the oil pump housing. Wonder if they are and this is causing pressure loss.

Looks like im ripping this thing apart again 

[Hyundai i30 1.4]

Hi there guys! Sorry for the late update, I was pretty busy lately. The oil pressure issue is still there on my I30, I have changed the oil pump and the timing chain so far but the problem is still there.

[TerryT]

Hi there guys! Sorry for the late update, I was pretty busy lately. The oil pressure issue is still there on my I30, I have changed the oil pump and the timing chain so far but the problem is still there.

Wow, your low pressure problem has been going for five months, and still undiagnosed! 

Just to clarify something, did you change the oil pump and timing chain or did your workshop do the job?

I'll have to re-examine my posted 'summary of events' (26th March) to refresh myself but I think I'll  be conceding defeat. 

[Hyundai i30 1.4]

Yes, sorry, the workshop did the job, not me, they said they tried everything and the only thing left to do is to tear apart the engine, there might be an worn crankshaft bearings problem, that’s why I left it unsolved because I don’t know if I m going to invest that much money in it 🤷

[TerryT]

Yes, sorry, the workshop did the job, not me, they said they tried everything and the only thing left to do is to tear apart the engine, there might be an worn crankshaft bearings problem, that’s why I left it unsolved because I don’t know if I m going to invest that much money in it 🤷

@ Hyundaii30.  Have you fixed the low oil pressure problem on your car?  What was the problem?