P1364 - Valve lift control cylinder 5 + misfire 5
 

Was driving on a slow road when I heard an unusual sound. Stopped and the engine was running rough. I had just added oil the day before and checked the oil cap but it is on tight. Pulled these codes off the durametric. Any one seen this before? Searching did not yield any threads with an outcome. Any help welcome thanks in advance. 2002 C2 Tip

Any chance its the lift control solenoid bracket?

https://cimg4.ibsrv.net/gimg/rennlis...77b6e086ca.jpg

Something similar (p1371) ...but cylinder 6, instead of 5

https://rennlist.com/forums/996-foru...questions.html

Check your coil pack for that cylinder. Was it wet that day?

Thanks. No it was completely dry and all coils done about 2yrs ago. Will check thou.

I would stop,, and check for a broken valve spring(s). Sometimes they break and stay put, until they shred and go everywhere..

Car is going to my indy next week. Will not be running it. Fingers crossed its not something $$$$.

Ok, I really hate to be this guy and hope I am totally off base here, but I have to mention that cylinder 5 misfires occurred on my 997.1 both times before complete engine failures (as well as on a friends 997, same cylinder). Each time it showed up as a small error, similar to what you describe and show on the readout. Admittedly both times occurred while tracking the vehicle (same for friend) but I mention because the misfire code was each time what drew my attention and visit to an Indy like yours. The first completely detonated the case rendering so much damage that it was impossible to tell cause though most assumed IMS.

The second occurred following a similar misfire code on C5. Though I recognized it was concerning to have a similar warning, having replaced the motor and updated the IMS, I assumed it was a coincidence and the Indy wasn’t concerned so why would I be? Looking back I think I just had the same issue happen on two different engines. The second failure wasn’t nearly as catastrophic and was repairable with an engine rebuild which wasn’t fun, but not nearly as bad as the first. I only learned of the third through various follow up discussions, but didn’t dig for details as the car had been long since sold.

It’s been a while but I believe the second was the C5 lifter “holder” failing and falling into the inner workings of the engine. They were able to rebuild unlike the first time but please take this omen seriously and do additional research because it is likely not a coincidence that we all had C5 misfires. Given my hindsight of the three incidents now, I would recommend that with a C5 misfire they pull the engine and review the condition of the lifters and components, replacing as appropriate.

Know you don’t want to hear this and this recommendation means a hefty repair bill, but my hopefully this helps you see a possible pattern and dig deeper to make a more educated decisions. I promise you a complete rebuild is painful and a complete replacement is even more so...

When I see these codes the first thing I do is an oil change.. The systems use oil for hydraulic fluid, and often this can be a contributing factor.

Thank you Jake! I will take your advise and give that a try before it goes to the indy. Much appreciated.

Oil changed. Was last done 4months ago and was pretty dirty.. but zero metal. Misfire condition persists. Indy did a compression test and cylinder 5 has no compression. They suspect valve is gunked up and stuck open.

Check posts 15,27,28,31 and 33 on the thread in my first response. I am not suggesting you do the same......it is just a point of reference on a recommendation (from experts) that ended with "good" results.

My indy is basically suggesting the same, except to use valve cleaner vs ATF. I am NOT pulling the motor out and doing valve replacement.... I will walk away from the car if the valve cleaner/ATF approach does not work, so I do not really have much to lose. Going away for a few days for holiday. Not doing anything till I get back, pretty upsetting news.

Failed valve seat can cause that,, Easy enough to check with a bore scope and removing intake and header..