1999 C2 Code P1531 Timing Solenoid

Hey Everyone, I have an early build (2/98) 1999 C2 manual transmission with about 72k miles. Last night while driving slowly through the neighborhood, the Check Engine light came on. I have the Durametric (enthusiast), so as soon as I got home I plugged it in and got the following code: P1531 - Camshaft adjustment bank 1 I turned on the engine and I checked the cam deviation in the Actual Values section. I have Bank 1: 3, Bank 2: 0. When I first got the Durametric about a month ago I checked those values and they were around 1 & 0 or 2 & 0 (checked at different times), so it definitely changed. I cleared the code, but the cam deviation never changed and the code came right back. I then went into the Activations section and I activated the bank 1 solenoid. The idle dropped for a second. I did the same on bank 2 and got the same result, idle dropped. At this point I thought it could be a glitchy connection, but I was perplexed. This morning I went back out and activated the solenoid with the engine off to see if I could hear anything. I could not. I was right next to bank 1, but too far away from bank 2. I then turned on the engine and activated each side again. However, this time activating bank 1 did nothing. Activating bank 2 dropped the idle for a second. I repeated this process several times, and got the same result each time: Bank 1 nothing, bank 2 idle drop. The only difference from last night to this morning is that last night the engine was a full operating temp as I had just gone for a drive, whereas this morning, it was cold. I searched around and found this link: https://rennlist.com/forums/996-foru...-solenoid.html Solid information in there. I read about how I should check the ECU for a burnt smell and also check the connections. It seems like I have to replace the bank 1 timing solenoid. However, I wanted to ask if there are there any other troubleshooting tips that anyone could recommend before I jump to that to ensure that the solenoid is 100% the problem? It's a pretty expensive piece and although I'm considering changing it myself, it's a time consuming process, so I want to make sure I don't waste time or money. Now, if I do have to replace the solenoid, and I do decide to do it myself, I have some questions: 1. Based on what I have found so far, it looks like the cam/valve cover needs to come off. Is that correct? 2. A few people said to loosen the engine mounts and drop the engine a few inches. How hard is this if working on the floor with jack stands? Any procedure detailing how to do this? I haven't searched, but asking in the hopes that someone has a link handy. 3. Does anyone know where I can get a copy of the service manual? Having the step-by-step would be great for this process. I've always purchased FSM for every car I've owned as I love to do my own work and I'm decently handy. However, I'm having a bit of trouble finding one for the 1999 996. These are the parts I've put together should I have to go down the replace solenoid route: 996-605-901-00 - Porsche Solenoid for Variable Cam Adjuster Cyl. 1-3 996-105-223-52 - Porsche Cover Piece with Seal for Camshaft Adjuster Solenoid on Valve Cover 000-043-305-60 - Porsche Sealing Compound - Loctite 5900 If anyone has ever done this themselves on a 1999 C2, any input, tips, tricks, advice, etc. would be HUGELY appreciated. The final question: Is it safe to drive it with that fault knowing that the have a cam deviation of 3,0? This is my daily, so having it out of commission needs to be kept to a minimum. I'm sure I forgot to list some info, but that's all I've got for now. Thanks in advance!

I have done this plenty of times but ... 1531 can also be the whole Variocam actuator (which comes with its own solenoid valve) needing to be replaced. This is a medium complex job requiring some special tools. If you are handy and have the tool, you should be able to handle this.

Oh, ok, didn't know that it could also be the entire actuator assembly. How would I troubleshoot this to determine which one is the culprit? I'm a very handy guy, but I don't have the specialty tools nor the specific knowledge of the M96 engine. Meaning, with a step-by-step process as is usually offered in a FSM, I can get stuff done.

I had this exact code on my 99. Twice, one for bank 1 and one for bank 2. It�s usually the solenoid that fails that causes this code. The ECU has a transistor that drives both solenoids on the same circuit. You can measure the resistance of the solenoid and that will tell you if it�s bad or good. You can inspect the wiring as well. The only advice I�d give you is that you might want to proactively replace the tensioner pads, both top and bottom, while you are in there. For replacement of the solenoid and the tensioner pads both, Yes, the valve cover has to come off, the scavenger oil pump may need to be handled, etc. The shop that did this for me charged 7-9 hours for one side, and 8-10 for the other (one side has the AC compressor in the way). They also said the exhaust headers needed to come off, and planned for a broken bolt, due to age, but my car didn�t have that issue.

Use the scanner to monitor the actual cam shaft angle (in relation to crank shaft). While idling, activate Variocam on the offending bank, you should see a big jump in cam shaft angle. And turn it off, it should come back the other way. If it does not, then turn engine off, activate Variocam solenoid, if it clicks, then solenoid is good, Actuator is bad. If it does not click then Solenoid is bad, Actuator is unknown. It has been my experience that the Actuator on bank 1 fails while the one on bank 2 never fails. I don't know why. You have problem on bank 1, you activate Variocam nothing changes, and you can't hear it click. Maybe it's just the solenoid. Which is now $500.