Sounds like pistons hitting the heads

[mf7lakes]

after 2 days being parked - pressed the start button - oops, didn't press brake pedal - then press brake pedal & hit the button again- engine starts - with a great rattling of valves/lifters/pistons metallic sounds of the engine tearing itself apart.

shut the thing down asap -- waited about 1 minute -- hit the start button again - rattles once then smooths out to normal sewing-machine-like purr.

WTFFFF?????

the engine malfunction icon was illuminated - so hopefully it threw out some codes that show what was going on when this happened.

Have appointment tomorrow w/dealer.... will advise

Anybody else have this ?????

 

[xiaphin]

Certain Nissans when sitting for a while (couple weeks) make noise when started. Lack of lubrication in the head since all oil has drained into the crankcase. Once lubricated noise goes away. Havent had this issue with the Genesis although what you described sounds similar but I'm not a mechanic.

Towing the vehicle to the dealer?

 

[Mark_888]

I don't know if it is the same problem, but many have reported a similar problem with the V8. It turns out that sometimes the valves are in wrong starting position, especially in cold weather or when car parked on a slope. It has been most often reported when turning the engine on for a very short time and then off, and then restarting, which somehow gets the valves in wrong position for next start. There are lots of threads/posts on this.

 

[unluckier]

I don't know if it is the same problem, but many have reported a similar problem with the V8. It turns out that sometimes the valves are in wrong starting position, especially in cold weather or when car parked on a slope. It has been most often reported when turning the engine on for a very short time and then off, and then restarting, which somehow gets the valves in wrong position for next start. There are lots of threads/posts on this.

How can the valves be in the wrong position when they are mechanically linked. The cylinders would over pressure and cause catachrestic failure.

 

[mf7lakes]

Thanks Mark - I'll search the forums for valves in wrong position. I really want to see the codes that the computer has stored tomorrow.

 

[Mark_888]

How can the valves be in the wrong position when they are mechanically linked. The cylinders would over pressure and cause catachrestic failure.

Maybe it is not the valves, but some other parts. Check the other threads/posts on this subject.

 

[scottdk]

after 2 days being parked - pressed the start button - oops, didn't press brake pedal - then press brake pedal & hit the button again- engine starts - with a great rattling of valves/lifters/pistons metallic sounds of the engine tearing itself apart.

shut the thing down asap -- waited about 1 minute -- hit the start button again - rattles once then smooths out to normal sewing-machine-like purr.

WTFFFF?????

the engine malfunction icon was illuminated - so hopefully it threw out some codes that show what was going on when this happened.

Have appointment tomorrow w/dealer.... will advise

Anybody else have this ?????

Try this thread

http://www.genesisowners.com/hyundai-genesis-forum/showthread.php?t=3781&highlight=engine+shaking

 

[mf7lakes]

After reviewing several DOZEN different posts - this is the link to the thread that exactly describes what I experienced. This started back in 2009 - and obviously still going on with the 2012 model 4.6 ....... mine has 11,000 miles.

http://www.genesisowners.com/hyundai-genesis-forum/showthread.php?t=3781&highlight=engine+shaking

 

[veed]

never had this happen, but there have been several TSBs that weren't applied to my 2011 when i got it (dealer did after the fact for no addtl $$). i think there's something in that thread about a SW update that addresses the issue ...

... which is probably a word to the wise who buy used (esp from a dealer). make 'em apply all TSBs and SW updates BEFORE you drive it off the lot.

 

[Mark_888]

never had this happen, but there have been several TSBs that weren't applied to my 2011 when i got it (dealer did after the fact for no addtl $$). i think there's something in that thread about a SW update that addresses the issue ...

... which is probably a word to the wise who buy used (esp from a dealer). make 'em apply all TSBs and SW updates BEFORE you drive it off the lot.

I don't believe this is a software issue. It has to do with some parts of the engine not being the correct position at startup. It seems to happen when the engine is started only breifly and then shut down, and then the problem occurs at restart. Happens more often in cold weather or when car is parked on steep grade.

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[technopeasant]

The top end valve timing is regulated by oil pressure.
Try a lighter viscousity oil in winter like 0w-20

Could be a clogged oil filter/screen for variable valve timing mechanism.

 

[unluckier]

The top end valve timing is regulated by oil pressure.
Try a lighter viscousity oil in winter like 0w-20

Could be a clogged oil filter/screen for variable valve timing mechanism.

I do agree with this, or even using a good synthetic light oil would work best.

 

[mf7lakes]

OK guys -- no codes showing in the computer when at dealership (of course!!!)....gave me a loaner and the 4.6 spent the night at the shop. supposedly, they were going to start it yesterday evening but shut it off before it got below high idle and then let it set overnight (about 34d F here this morning).

Then they were going to start it early this morning to try and duplicate the prob.

Well, its now about 10:00 a.m. and I haven't heard anything from them..........maybe they had success.

The car is serviced with Hyundai oil filter and 5W20 synthetic (last August).......nothing is plugged up on this car.

EDIT: in the other thread shown above, there was a remark by one tech guy that the engine malfunction codes are erased after the engine start button is used 3 cycles......this might apply here................4:30 pm could not duplicate condition at dealership......

 

[66nexus]

Long time lurker here (though just recently registered). Hate to bump, but I've been reading the threads on this issue and it seems that a) warming the car before shutdown prevents further issues b) TSB ecu reset from dealer solves it

However, some posters state they still had 'some' issues after doing both 'a' and 'b'. I still want a Gen, but this is making me reconsider my 4.6 choice (and perhaps just going for a 09-11 3.8)

Perhaps it only 'seems' worse because the info is all in this thread? (as in, there has to be thousands of 4.6's that DON'T have issues...right?)

 

[homeofstone]

Long time lurker here (though just recently registered). Hate to bump, but I've been reading the threads on this issue and it seems that a) warming the car before shutdown prevents further issues b) TSB ecu reset from dealer solves it

However, some posters state they still had 'some' issues after doing both 'a' and 'b'. I still want a Gen, but this is making me reconsider my 4.6 choice (and perhaps just going for a 09-11 3.8)

Perhaps it only 'seems' worse because the info is all in this thread? (as in, there has to be thousands of 4.6's that DON'T have issues...right?)

86,000+ miles on my 2011 4.6 w/tech pkg. , no problems, near perfect car. Still with original brakes. No engine noise, no oil use, no electrical problem.

 

[66nexus]

86,000+ miles on my 2011 4.6 w/tech pkg. , no problems, near perfect car. Still with original brakes. No engine noise, no oil use, no electrical problem.

That's reassuring and I do appreciate the response. Sometimes I wish there were counter threads for threads like this. I'm within a month of getting the car and I suppose I'm getting those last minute jitters (the most vulnerable point when about to make a purchase)

 

[Flgatorfan]

My '11 4.6 has been trouble free too.

 

[66nexus]

^Thanks guys for the reassurance. I suppose there's no such thing as the 100% perfect/problem free car, but the Genesis seems like a good platform to go with either way.

 

[mf7lakes]

since the initial incident, I have put on another 3000 miles and ....... it has run perfectly with no issues at all..............but I do let it warm up before I shut it down -- "just in case"

 

[66nexus]

Finally got over the fear of this happening and pulled the plug on a '10 4.6 Tech, I let it warm up and all on every start. Thanks guys!