loud ticking off-throttle below 2600rpm when hot - 986 Forum - The Community for Porsche Boxster & Cayman Owners

wmjosiah · 08-17-2018, 05:17 AM

Hi all,
As the subject says, I'm suddenly getting a loud ticking - sounds like a plastic fan hitting its shroud, or maybe electrical arcing, or vaguely like lifter tap, but not really, off-throttle only, and only when hot - the car is silent when cold, runs and idles smooth and quiet. When the car has warmed up - usually around 15-20 minutes of driving, the problem starts, intermittently at first, and then reliably and repeatably after about half an hour. The minute you get back on throttle or above 2600rpm it stops. If I let off the throttle at say 3100rpm, the second it gets to 2600rpm the noise starts, and if I get back on throttle, it goes away again immediately. It's exactly in time with the RPMs - gets slower as revs drop etc.

This started after a hard rainstorm. I got a P1341. I took apart the bank 1 VarioCam connector and cleaned it. Cleared the code. Code did not come back. Ticking problem went away. Drove it for a few days, then took it through a carwash and the ticking problem reappeared immediately after getting out of the carwash, but no code. It's been about 1000 miles now and I have no new codes. We hooked up a Snap-On computer to it while driving it, and the timing claims to be in spec and I have no misfires on any cylinders. If this noise was not happening, I wouldn't know there was anything wrong. The car runs strong, idles smooth, runs up to redline eagerly like normal, is getting the same gas mileage as usual.

I checked my coils. #2 had a large crack in it and the others were all cracked at least somewhat. They look original. I replaced #2 with the Beru replacement that's recommended (and did all my plugs while I was at it), then discovered it was an updated part so I ordered the other five and will be installing them Monday, but I think this is irrelevant.

Any ideas? I searched the forums and couldn't find anything that sounded like this problem. Thanks in advance.

alm001 · 08-17-2018, 06:26 AM

I had a similar ticking (Driver side) at idle when very hot. My thought was oil pressure issues - I think I was down about 1/2 a quart. I did an oil change last weekend and replaced the oil pressure relief valve with the updated part number. I have not heard it come back. I intend to put a gauge for oil pressure in the car at some point soon.

Are you due for an oil change soon? Is your oil filled to the specified level?

wmjosiah · 08-17-2018, 06:36 AM

It was in the middle of the stick, and after searching the forums, I filled it up to the top. I'm about 2000 miles into an oil change.

Quote:

Originally Posted by alm001

I had a similar ticking (Driver side) at idle when very hot. My thought was oil pressure issues - I think I was down about 1/2 a quart. I did an oil change last weekend and replaced the oil pressure relief valve with the updated part number. I have not heard it come back. I intend to put a gauge for oil pressure in the car at some point soon.

Are you due for an oil change soon? Is your oil filled to the specified level?

wmjosiah · 08-17-2018, 06:41 AM

Good to know about the oil pressure relief valve though. I do have some ticking at idle when hot as well, though much quieter than what I'm talking about, so I'll replace that too. Thanks!

Quote:

Originally Posted by alm001

I had a similar ticking (Driver side) at idle when very hot. My thought was oil pressure issues - I think I was down about 1/2 a quart. I did an oil change last weekend and replaced the oil pressure relief valve with the updated part number. I have not heard it come back. I intend to put a gauge for oil pressure in the car at some point soon.

Are you due for an oil change soon? Is your oil filled to the specified level?

wmjosiah · 08-17-2018, 10:44 AM

For the record, oil level shouldn't affect oil pressure, AFAIK, unless your oil is so low that the oil pump starves for oil, at which point you have much more serious issues.

Quote:

Originally Posted by alm001

I had a similar ticking (Driver side) at idle when very hot. My thought was oil pressure issues - I think I was down about 1/2 a quart. I did an oil change last weekend and replaced the oil pressure relief valve with the updated part number. I have not heard it come back. I intend to put a gauge for oil pressure in the car at some point soon.

Are you due for an oil change soon? Is your oil filled to the specified level?

wmjosiah · 08-21-2018, 06:13 PM

Well, I replaced all the coils, updated to the new oil pressure relief valve cylinder and spring, and changed the oil... and in the process I found lots of green rubber bits stuck in the oil filter, exactly as described in this thread: Green chunky bits in oil Filter - Pelican Parts Forums

That, in combination with the occasional P1341 and the awful-sounding ticking off throttle when hot below 2600rpm (not mentioned in the thread above - if this wasn't happening I would keep driving the car), which seems like internal bits of the engine contacting themselves - seems a bad idea to continue driving the car, and I'm probably in for taking the motor out and replacing tensioners and Variocam actuator on at least one side. If I fix this, I'll update this thread with how it turned out.

Quote:

Originally Posted by wmjosiah

For the record, oil level shouldn't affect oil pressure, AFAIK, unless your oil is so low that the oil pump starves for oil, at which point you have much more serious issues.

wmjosiah · 08-27-2018, 08:38 AM

Update: Decided to drive the car to DC and back (from MA) anyway as I'd been planning on that trip for a long time. The car was a joy to drive and performed admirably. It runs perfectly, threw no codes, but still makes that alarming noise sometimes under the conditions previously described, though it's doing it less and less often and less loudly as time goes on, it seems. I'm sure I need to pull it apart to fix it, but it doesn't seem to be affecting the performance or gas mileage of the motor in any way.

Leebherron · 08-27-2018, 10:01 AM

Just checking...are you using hi test gas ?

wmjosiah · 08-28-2018, 11:34 AM

Always 93! Thanks though

Quote:

Originally Posted by Leebherron

Just checking...are you using hi test gas ?

wmjosiah · 03-05-2019, 05:22 PM

After changing the oil filter and reading a bunch of forum posts about how this is a VarioCam solonoid seal, and how maybe the motor is designed in such a way that perhaps that seal isn't even needed, and driving it several more thousand miles, with that noise occurring less and less frequently, and in the last few thousand miles, not at all, I feel it necessary to post an update: This isn't happening at all anymore, and hasn't for several months and several thousand miles. Just letting the seal disintegrate and letting the motor get all of the seal-bits out of its system appears, at least so far, to be a valid course of action. The car runs normally, doesn't make any untoward noises, doesn't burn any oil, gets normal gas mileage, and is still an absolute joy to drive. I'm sure this isn't the "right" course of action, but for a $7000 car with 170K on it that doesn't appear to have any symptoms at this point, I'm just going to leave it alone unless I notice any further problems.

Starter986 · 03-06-2019, 05:16 AM

Quote:

Originally Posted by wmjosiah

After changing the oil filter and reading a bunch of forum posts about how this is a VarioCam solonoid seal, and how maybe the motor is designed in such a way that perhaps that seal isn't even needed, and driving it several more thousand miles, with that noise occurring less and less frequently, and in the last few thousand miles, not at all, I feel it necessary to post an update: This isn't happening at all anymore, and hasn't for several months and several thousand miles. Just letting the seal disintegrate and letting the motor get all of the seal-bits out of its system appears, at least so far, to be a valid course of action. The car runs normally, doesn't make any untoward noises, doesn't burn any oil, gets normal gas mileage, and is still an absolute joy to drive. I'm sure this isn't the "right" course of action, but for a $7000 car with 170K on it that doesn't appear to have any symptoms at this point, I'm just going to leave it alone unless I notice any further problems.

Thanks for the update!

wmjosiah · 07-20-2020, 05:57 PM

This came back, badly and somewhat suddenly, at 182K. It seems to be happening a lot more in the very hot weather we're having right now. Does anyone know what 2600rpm has to do with anything? It's extremely consistent - above 2600rpm, no noise. Take foot off throttle, at precisely indicated 2600rpm, it starts, and now it's LOUD. Doesn't sound good, but also doesn't seem to affect the way the car runs at all. I'm thinking I'll try replacing the Variocam solonoid on bank 1, but I'm open to other ideas. I'm still not getting any code. Noise appears to be coming from right side of engine.

blue62 · 07-20-2020, 07:12 PM

Quote:

Originally Posted by wmjosiah

This came back, badly and somewhat suddenly, at 182K. It seems to be happening a lot more in the very hot weather we're having right now. Does anyone know what 2600rpm has to do with anything? It's extremely consistent - above 2600rpm, no noise. Take foot off throttle, at precisely indicated 2600rpm, it starts, and now it's LOUD. Doesn't sound good, but also doesn't seem to affect the way the car runs at all. I'm thinking I'll try replacing the Variocam solonoid on bank 1, but I'm open to other ideas. I'm still not getting any code. Noise appears to be coming from right side of engine.

Is 2600 RPM the threshold for Variocam actuation?
Have you checked your camshaft deviation numbers?
Perhaps the camshaft chain tensioners are shot creating slop in the chains when the Variocam actuators are retracted.