What do you think is causing this?

Meaker · 31 Dec 2018 at 11:29

Engine warning light came on again on my Veloster Turbo.

Car is tuned but not to a silly degree, ran fine for 2 months and 3000 miles.

Took it in for a service from Hyundai dealer, they have admitted to fitting the wrong spark plugs at this time.

Ran incorrect spark plugs during dyno day but was performing normally. On the way back it started stuttering beyond 40-50% throttle.

Took it in for them to have a look, they replaced with the correct spark plugs, drove normally for a couple of days and the issue came back but different. Rough idle and stutters at 90% throttle.

Took it in again and they diagnosed a faulty spark plug, they replaced again. This is the result of a new spark plug and about 800 miles of driving (Up to Edinburgh and back again with a little run around now and again in between). Decided to get my own tools and take a look.

This is from cylinder 1, tried removing cylinder 2 spark plug but would not budge. 3 and 4 came out without too much trouble and looked fairly normal:

OBD says misfires are cylinder 1 and 2 so I would not be surprised if 2 is in the same or worse state than 1.

My guess is either coil damage or blocked injectors from the initial misfiring?

Orionaut · 31 Dec 2018 at 11:56

Looks like bad detonation.

You really want to get No 2 out and see what it is like and resolving the issue before continuing to use the car.

If No 2 really wont come out with normal hand pressure then you might require specialist help. Snapped off spark plugs can be a complete nightmare, especially on modern cars where access to the damaged threads isn't so good. If you break it in your own driveway you might end up having to have it recovered to somebody who can deal with it if you cant find anybody who can come to you (I know somebody in SW Surrey area who does this sort of work mobile, but he only works for traders)

Holed pistons are a distinct possibility if you continue to use the car and are melting spark plugs so readily

Meaker · 31 Dec 2018 at 12:12

It will start but I intend to take it back to them on Wednesday to take a look again, wont use it other than taking it there at this point.

Dangerous Dave · 31 Dec 2018 at 12:53

I'd get the remap taken off it before doing anyway thing else, it looks like it has bad detonation which may have damaged a piston/valve.

acemastr · 31 Dec 2018 at 13:13

Get that tune off of it, your tuner should have noticed bad spark plugs before he even started tuning it (if he's good, my bike guy is) and would definitely have noticed detonation on the dyno.

If hyundai ask why there's a low start count (ECUs count number of starts, remap will probably reset to zero) simply say you took the battery negative off.

Meaker · 31 Dec 2018 at 13:24

The remap was done shortly after getting it and it ran fine for 3000 miles over 2 months, the original spark plugs I bought it with never had any issues. It only started misbehaving after they replaced them with the wrong ones.

HoneyBadger · 31 Dec 2018 at 14:13

Take the remap off and diagnose and fix the car as it was originally designed, then put the remap back on. Basic 101.

You have a fuel/detonation issue and the remap will only confuse things. Just because it appears to have been fine for 3k, doesn’t mean it is/has.

jpaul · 31 Dec 2018 at 14:19

Meaker said:
Ran incorrect spark plugs during dyno day but was performing normally. On the way back it started stuttering beyond 40-50% throttle.

... so something occurred during the dyno ? did that proceed normally, cooling, rev-limiter ?

Meaker · 31 Dec 2018 at 14:53

There was a couple of dips in the final run which I think might have been the steering being knocked slightly but otherwise it was smooth and normal.

chaparral · 31 Dec 2018 at 15:10

Googling pictures of spark plugs that look like that says is caused by "pre-ignition"

Orionaut · 31 Dec 2018 at 15:25

chaparral said:
Googling pictures of spark plugs that look like that says is caused by "pre-ignition"

Further to what I said earlier.

Is this a GDI engine (Autodata doesn't seem to be very clear on this model range)

If this is a GDI and something has ****** up the injection profile, Premature Injection <Erm, Cough!

> could be causing this. As others have said. Second step is to revert to standard tune (First is to remove the stuck plug and make sure there isn't any other damage, really it is!)

Meaker · 31 Dec 2018 at 15:48

It is a GDI for certain since they call it a T-GDI engine.

Simon · 31 Dec 2018 at 16:08

Might be low speed pre ignition. Will be made worse due to more boost at the lower speeds

IAmATeaf · 31 Dec 2018 at 19:28

As the cars been back to the dealers won’t they have spotted the tune? Maybe not have raised it as an issue at the time due to themfinding incorrect plugs but maybe if there is more damage they may have made a note?

lordrobs · 1 Jan 2019 at 12:22

What fuel was it mapped on and what have you been running since?

Frozennova · 1 Jan 2019 at 19:22

Can you photo number 1 spark 1 showing the porcelain?

Once it starts to detonate/pre-ignite it's a vicious cycle, once the piston starts to become pitted it makes it more prone to continue as that pitted piston creates hot spots

Simon said:
Might be low speed pre ignition. Will be made worse due to more boost at the lower speeds

That would be my first port of call. Particularly as this is just after a service after 3k miles of running fine.

I suspect the tuner may have dropped in a folder plug as part of the tune and now the main dealer have done a service and gone back to a hotter plug LSPI has reared its ugly head.

Edit: As daft as it sounds OP this could also be oil related too

Meaker · 2 Jan 2019 at 13:19

lordrobs said:
What fuel was it mapped on and what have you been running since?

Momentum 99 on both counts.

Frozennova said:
Can you photo number 1 spark 1 showing the porcelain?

Once it starts to detonate/pre-ignite it's a vicious cycle, once the piston starts to become pitted it makes it more prone to continue as that pitted piston creates hot spots

That would be my first port of call. Particularly as this is just after a service after 3k miles of running fine.

I suspect the tuner may have dropped in a folder plug as part of the tune and now the main dealer have done a service and gone back to a hotter plug LSPI has reared its ugly head.

Edit: As daft as it sounds OP this could also be oil related too

It's back in the shop now so I can't do more pictures. I don't believe any changes were made to the car for the tune. 186 -> 216 was the mapping. Note however it is a detuned engine from the 201 BHP american series with which it shares the same spark plugs and everything engine related.

I know during the service the oil was replaced but I believe the normal and turbo use the same 10W-30.

So really it was a 7% uplift tune from rated.

Armageus · 2 Jan 2019 at 13:41

What year of Veloster is it?

I assume the "R6" on the plug is the heat range, if so there's some reference that Heat Range 6 plugs are too hot, and you should use a 7 rated plug (and apparently was changed on the 2014+ model)

https://www.velosterturbo.org/forum/veloster-maintenance/21425-spark-plugs.html

Oddly on Bosch's site it lists the both the YR6NI332S (heat 6) and the 9624 (heat 8)
https://www.boschautoparts.com/en/auto/spark-plugs/double-iridium-spark-plugs?partId=YR6NI332S
https://www.boschautoparts.com/en/auto/spark-plugs/double-iridium-spark-plugs?partId=9624
https://www.boschautoparts.com/en/auto/spark-plugs/double-iridium-spark-plugs?partId=YR6NI332S

Meaker · 2 Jan 2019 at 13:44

That is interesting. I could order a set and swap them out myself.

Frozennova · 2 Jan 2019 at 13:51

Armageus said:
What year of Veloster is it?

I assume the "R6" on the plug is the heat range, if so there's some reference that Heat Range 6 plugs are too hot, and you should use a 7 rated plug (and apparently was changed on the 2014+ model)

https://www.velosterturbo.org/forum/veloster-maintenance/21425-spark-plugs.html

Oddly on Bosch's site it lists the both the YR6NI332S (heat 6) and the 9624 (heat 8)
https://www.boschautoparts.com/en/auto/spark-plugs/double-iridium-spark-plugs?partId=YR6NI332S
https://www.boschautoparts.com/en/auto/spark-plugs/double-iridium-spark-plugs?partId=9624

Just to confuse matters, they're referring to NGK Heat ranges in that thread, Bosch go the opposite way.

https://matchlessclueless.com/wp-content/uploads/2011/05/Temperature-range-comparison.jpg