Variocam Issue? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

freserf · 12-08-2020, 11:18 AM

The previous owner of my 1997 Porsche Boxster listed the following problem for the engine. "Valve train noise at high rpm. Possible variocam solenoid bad. No issue at low rpm." The following codes showed up when I revved the engine or were already set when I hooked up my reader. P0300, P0301, P0302, P0303, P0341, P1319, P1313, P1314, and P1315. I did experience the misfires without driving the vehicle and I understand what they mean ... trouble with bank 1 misfire and possible camshaft sensor issues. The emission codes are just warnings because of the misfires. Stop driving to prevent damage. So far I have checked and confirmed good camshaft sensor and compared both variocam solenoids at about 12.7ohms with good voltage to both. I can also hear them clicking when testing with my power supply. Having worked with many types of solenoids, I know they can test fine, but not really work well as they age. The car has 86000 miles and the documented history is not the best. I have also read through many posts from various sites related to this similar issue and still do not have an "Aha", idea to run with. Spark plugs were extremely worn and coils looked good ... and there was no signs of broken plastic parts or metal in the oil or filter.

I am leaning towards timing chain wear or more likely tensioner pad wear even though I haven't seen evidence so far. I want to pull bank 1 side head cover and visually check the tensioner pads. Do I need the special P253 tool or just something to hold the ends of the camshafts in place in order to pull the cover. I don't mind being a perfectionist, but the KISS method works best for me.

Lastly, there is a loud rattle for about 1 second on start up and read this may be normal and using a different grade oil may reduce this ...

Is it possible due to failing IMS since it is driving bank 1 to cause these symptoms?

Just want some input from those who have experienced similar situation. Thanks for any input and have a great day.

BYprodriver · 12-08-2020, 12:16 PM

Be more optimistic, you are having misfire codes Install new spark plugs & see what happens after clearing all the codes. If one cylinder misfires it can cause the next cylinder to misfire. Be sure all coil leads are properly installed.

freserf · 12-08-2020, 03:12 PM

Thanks for the reply ... just finished replacing Bosch FR6LDC with Bosch FR7LDC+. All were very worn but only bank 1 misfires so far ... see attached photo.

I can only go on what information was given and what I have read so far ... this is my first Porsche project ... so there is a large learning curve. If it turns out to be just some badly worn spark plugs to have it run smooth, that would be great. She wasn't treated well and I enjoy the challenge.

JFP in PA · 12-09-2020, 06:19 AM

From the looks of the oil on that plug, your plug tubes are leaking.

freserf · 12-09-2020, 07:39 AM

That is an affirmative ... I was debating with myself on whether to buy a puller or just use a makeshift long bolt head to remove them and replace with the new ones that arrived this week. I can always stock my toolbox, but as I get older and hopefully a little wiser ... I've learned to adapt with what I have on hand. I am sure they are the original and unfortunately, o-rings don't last forever. Could be a little or a lot stuck though. Had any issues removing these?

szube · 12-09-2020, 10:40 AM

A T-handle boat drain plug works well to pull the plug tubes.

Jgkram · 12-09-2020, 11:13 AM

I used the long bolt head "tool" and it works just fine. Hook it behind the tubes and they pop out just fine. Good luck and welcome to our world.

JFP in PA · 12-09-2020, 11:42 AM

And, if anyone is interested, somebody in the aftermarket (Rauch and Spiegel) now makes the tubes in aluminum, totally eliminating the tendency for the OEM plastic tubes to deform and/or crack over time.............

traveno · 12-09-2020, 03:21 PM

Quote:

Originally Posted by JFP in PA

And, if anyone is interested, somebody in the aftermarket (Rauch and Spiegel) now makes the tubes in aluminum, totally eliminating the tendency for the OEM plastic tubes to deform and/or crack over time.............

Those looks beautiful. I just replaced mine with new plastic tubes. Otherwise I could try to justify buying a set of these. Maybe I’ll find a set in my stocking this Christmas. I hope!

freserf · 12-10-2020, 08:58 AM

Thanks for the replies ... I like the boat plug method, unfortunately I sold my boat about 10 years ago. I tried several different make shift tools ... the head of a carriage bolt and a set of measuring calipers slightly modified. The tubes did not want to let go so I ended up removing the outer plastic to remove the large o-ring and then they decided to let go ... I hope I did not get any pieces into the head as they were very brittle.

The Rauch and Spiegel aluminum tubes look like a great idea ... I will probably get these if I do need to remove the head covers to replace solenoid or timing chain pads. I noticed that they also sell the puller tool ... tempting, but I'll hold off unless I decide to work on future Porsche Projects.

I plan to drop the car off the jack stands this evening or tomorrow and test the engine for repeat codes.

freserf · 12-11-2020, 08:54 AM

Well ... pulled the car out of the garage for testing. Fired up engine with new air filter, fresh fuel, oil, and spark plugs. The engine codes reappeared. Misfire on bank1 with camshaft position code P0341. I did notice that the engine ran fine until the secondary air blower timed out. If I let the codes set at idle ... which is rough, I could clear them and then slowly raise the RPM's up to about 2600 when I heard the timing chain rattle. Reset the codes and was able to hold the RPM's steady at about 1850 without any misfires.

So, I would like some input on what to try next. Idle at engine full temperature is rough due to the misfire detections ... but at cold startup idle is good until secondary air timeout. Able to hold RPM's up with no misfires.

What do you guys think?

blue62 · 12-11-2020, 09:17 AM

Quote:

Originally Posted by freserf

Well ... pulled the car out of the garage for testing. Fired up engine with new air filter, fresh fuel, oil, and spark plugs. The engine codes reappeared. Misfire on bank1 with camshaft position code P0341. I did notice that the engine ran fine until the secondary air blower timed out. If I let the codes set at idle ... which is rough, I could clear them and then slowly raise the RPM's up to about 2600 when I heard the timing chain rattle. Reset the codes and was able to hold the RPM's steady at about 1850 without any misfires.

So, I would like some input on what to try next. Idle at engine full temperature is rough due to the misfire detections ... but at cold startup idle is good until secondary air timeout. Able to hold RPM's up with no misfires.

What do you guys think?

P0341 is as you know cam position sensor1: signal implausible/implausible operating range/malfunction.
You stated that you tested it.
Did you test to see if signal is getting back to the DME over the entire operating range?
If everything tests good with the Cam position sensor and wiring then I would look at Camshaft deviation and Camshaft timing on bank one.

JFP in PA · 12-21-2020, 10:52 AM

freserf · 12-22-2020, 05:58 AM

Thanks JFP. I was about 99.9% sure that the notch aligned with the arrow was TDC and that the alignment pin hole would be there also ... unfortunately I could not find pictures of the main pulley without the teardrop hole.

My main pulley does not have the teardrop hole, but has the notch ... see attached photos. It seems pretty simple to those who have worked on Porsche for years ... I have had mine about 2 months now and have never turned a wrench or driven one until now.

Just want to be correct before I start messing with the timing. Thanks again.

freserf · 12-23-2020, 05:08 AM

I now have the cylinder 1-3 head cover off and have found some wear on the timing chain rail guide from the IMS. Is there a way to replace this guide without removing the transmission?

freserf · 12-23-2020, 09:25 AM

Pulled the 1-3 cams and found very worn and broken guides on the variocam actuator. Also the chain rail guides for the IMS chain are worn ... not as bad, but still worn. It looks like I can remove upper and lower so I will see what happens. As far as the cams chain ... I am not sure but it looks like it may have skipped a tooth causing some of the rough running. Along with the wear on the variocam guides ... when they activate, it was enough to cause my misfires and camshaft position sensor codes.

I have only seen a tooth skipped engine code once in my life and that was on a Dodge Neon. No low end but good high end torque with that issue.

So I will probably go down the mini rebuild road replacing items that do not require engine removal. See attached photos.

blue62 · 12-23-2020, 09:53 AM

[QUOTE=freserf;628151]Pulled the 1-3 cams and found very worn and broken guides on the variocam actuator. Also the chain rail guides for the IMS chain are worn ... not as bad, but still worn. It looks like I can remove upper and lower so I will see what happens. As far as the cams chain ... I am not sure but it looks like it may have skipped a tooth causing some of the rough running. Along with the wear on the variocam guides ... when they activate, it was enough to cause my misfires and camshaft position sensor codes.

I have only seen a tooth skipped engine code once in my life and that was on a Dodge Neon. No low end but good high end torque with that issue.

So I will probably go down the mini rebuild road replacing items that do not require engine removal. See attached photos.
[img]http://986forum.com/forums/uploads02/IMG_20201223_12592116

[img]http://986forum.com/forums/uploads02/IMG_20201223_1302331608747871.jpg[/im

Looks like you have been able to do all this work with the engine still in the car.
I see six links between cam timing marks. Six is the correct number of links right??
Or am I looking at the wrong head in the picture???

geekshow · 02-08-2021, 02:11 PM

Hi all, I'm joining the Variocam actuator party with my 1998 2.5 which seems to have a list of problems that just gets longer.

The idle has never been great since I've owned it over the last few months, but the car drove well with no smoke, just a slight rattle on start-up.

Yesterday when going up a long hill, the engine lost power and the engine light came on - still ran, but a bit rough. Managed to get it home, but fault codes indicated misfires on bank 1, and the dreaded P1340 and P1531 indicating cam timing was out on bank 1 too.

A quick look underneath and it was clear to see the source of the problem - the variocam actuator wiring had come away, explaining my previous C1 fuse issues as the wiring presumably grounded.

I'm guessing in addtion to the actuator dying, bank 1 timing is also out too, although I've still to check the timing marks to confirm this. Durametric showed a steady 24 (degrees?) out for bank 1.