So,
I changed my plugs and fixed a coil pack on cylinder 3 for my LSJ.

Cylinder 3 was not getting good spark because the coil in the coil pack was covered in caked dry oil! I sanded off the coil to clean it up to bare metal, and oh boy, the car ran like never before!

Well, for 2 hours... After doing a hard pull for about the 16th time I noticed a strange vibration followed by a constant ticking sound when hard under boost, different than pinging as this was way more noticeable and frequent during the high rpms...

I freaked out and limped home. In the driveway I noticed zero problems underneath the car, everything looked good and was tight, as well, my car has no CELs at all.

This gave me confidence to rev the engine to redline various times. I did it slowly so that max vacuum would be maintained. I noticed that the ticking only gets loud when the car comes off vacuum (>-60 KPA), does this mean it's related to the SC? Or what else could it be that it only makes the ticking off vacuum?

Thanks

 

check the lash adjusters and tensioner

 

So remove the valve cover and I should be able to see these bad boys?

Thanks, thats all the advice I was needing, what to do next before taking it in to the shop.

 

Ya know what, I'm wondering if it's more of a puttering than a ticking, it's got both, but the puttering makes me wonder if it's an exhaust leak...

In fact, it would make sense that it's an exhaust leak because of the fact it doesn't come on until out of vacuum. There's not much exhaust being produced when you're on vacuum, so the exhaust pressure would be lower.

Also, engine doesn't make the ticking until out of vacuum, wouldn't it make it regardless if it was these? It redlined smooth as butter with no ticking when I was on max vacuum giving it just enough gas to raise RPMs.

Exhaust leak would make the most sense as my engine and supercharger only have 82,000 KM in total..

PS: Not disregarding your advice, just trying to make sense of the fact it doesn't sound like the engine given my vacuum/revving to redline test (I was trying to isolate out the supercharger from the engine).

 

It could be an exhaust leak, but i would still pull the cam over to check the valve train.

Question, why would you go out and beat on it 16 times?!? What are you reving to?

 

As I said, I'm not disregarding his advice, I AM going to do that. But some of that explanation does not add up to what I'm finding when I research Lash Adjusters and the Tensioner noises, my car doesn't sound like these vehicles (I went on YouTube and found confirmed LSJ's with both issues).

I'm trying to find an exhaust leak video now to confirm it sounds more like that.

Also, this thread is leading me to exhaust, it sounds like this is the issue:

Lash Adjustors mistaken for exhaust leak (manifold bolts loose)

Also, the 16 runs were after I did the tune up and everything ran great, so not AFTER the issue.

 

Went back out to the car, I was always listening for the noise in the timing chain area...

It didn't sound to me like the noise was coming from the passenger side, but more from the middle back of the engine, directly above the exhaust manifold is where I hear it the most!

I'm now trying to figure out what I got to do to get to those manifold bolts to try them first before ripping the valve cover off.

Any advice on tightening manifold bolts? I assume I just pop off the heat shield and I should find 4 on top and 5 on the bottom?

Cheers

 

EASY.

remove heat shield, tighten bolts.

there is a bolt tightning sequence you should use as well. Let me find it for u.

here it is...

 

Sweet as, thank you! This is happening at lunch hour.

 

Oh uh, I assume you did this from above the engine too? I was planning on doing it from up top just blindly feeling my way using that chart as reference... Is that doable, or does it have to go on a lift?

 

Well, I tightened them all, stupid f*cking noise persists.

Time to open the valve cover.

 

The cam cover is easy as pie to take off.

Let me kno what u find.

 

Well, the problem is solved once and for all. It turns out the ticking I heard was due to a broken flex pipe causing a major exhaust leak.

Dealership replaced the flex pipe, downpipe and cat... For free! There's a free fix on these until 2016, so check your stuff!

Thanks for helping me brain storm this.