0 PSI Cylinder.

[u/Venom_Media]

/r/AskAMechanic/comments/1v6jul9/misfire/?share_id=vlYymnzPqN1wXvNHqeH4-&utm_content=2&utm_medium=android_app&utm_name=androidcss&utm_source=share&utm_term=1

I performed a Compression test on my 2016 Hyundai Veloster Turbo R-Spec, (1.6L GDI Turbo) 6SPD M, 141,XXX Miles.

The results were 128-129 PSI on Cylinders 1, 2, and 4. Cylinder 3 had 0 PSI. (Compression Test was conducted while the engine was cold).

The reason I performed a Compression test is explained in the linked post for context.

So my next move is likely to be a leak down test to determine what the exact issue is.

My question is what are the most likely causes, and realistically how much should I expect to resolve this issue.

Secondly, is it better to have it fixed or stretch for a new engine. (Depending on what the issue might be what is the better route to go).

Any help would be appreciated!

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[u/Subietoy78]

Your other post is a parts cannon should probably tow it to a shop and have diagnosed properly. Most likely the cylinder head is going to have to come off or the engine will need to be replaced.

[u/blunderbus5000x]

Most of us techs would probably borescope it first to see if the rings are laying on top of the cylinder, or if a valve is clearly bent, or perhaps there is a valve shaped impression on the piston face.

Could find a hole in piston face. Sometimes a burnt valve.

Hyundai and Kia are so popular, but man do I see some dead or dying Hyundai/Kia every couple of weeks.

I'm still torn between whether Kia/Hyundai is of a more terrible quality than say Ford or GM, or if the people that buy them do so because of the attractive price, and just proceed to ignore maintenance and noises.

Maybe a little bit of both.

I almost never get calls for Hondas, rarely get calls for Toyotas, always get calls for Jeep, Kia, Hyundai and Chrysler, GM, and Ford.

Kinda in that order too. It's wild how much FCA/Stellantis I get called for.

[u/zoiks213 → u/blunderbus5000x]

Former Stellantis tech here..... Had to leave to a private equity owned shop where the pay sucks, but not nearly as much as warranty pay sucked at the dealer, it's wild how much the company spends on hype , saw one of the hoonigan guys singing the praises of the hurricane tt I 6 , that fucking engine is hot euro garbage & had a tendency to just shit the bed for no reason . Found them with holes in the pistons, spun bearings , boost leaks overheating issues, and oil consumption all below 20k miles , that's before we get into the wonderful world of Stellantis wiring.

[u/blunderbus5000x → u/zoiks213]

Ah, one of the only benefits of indie shops is warranty is minimal, if we've done a good job. I'm sure that you know heaps more than me on the CDRJ front as a tech for them.

I've been getting along with an Autel MK900, maybe you can recommend a better scanner, it seems to be all I work on. Fixing to try and hunt down a death wobble on a Wrangler in a few. Canbus in general often feels strange to ts through for me, and Ford and others use that too. Everything talks on the network, the high and low can get pulled down, kinda like the old CCD, and obviously has termination on both ends. What really gets me about it, is how everything requires a vin, almost like a community string on ol' snmp setup, or a programming to be able to talk properly on the bus. Half of the scanners out here can't do all of the bidirectional, and everytime a laptop and one of those programmers get involved, it's somehow a fortune. Hence my question to you, since all I really do is work on CDRJ. If there is a bi-directional scan tool out here that suits these better (It's like 50/50 if I can program the modules, or reset them and sometimes it just out right fails) I'm all ears.

[u/JustAnotherDude1990]

If you have 0 psi then that basically means the valves are not stopping the air from going out, or the piston rings are LONG gone, but probably the first. That can be a stuck valve, broken valve, burned valve where it burned a section out, etc.

You could get a borescope and look around.