Anyone Replace Variocam Actuator?
#31
RL Community Team
Rennlist Member
Rennlist Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Hi Guys!
Here is my experience. I had the hesitation and stumble problem. 991.1 4s. Stumble at around 2500 rpm even on the cruse control. On our cars there are 4 solenoid. 2 for the cams and 2 for the valves. I changed 1 cam and 1 valve cylinder 4-5-6. PROBLEM FIXED!! Have these solenoid checked I'm sure that's the answer to the stumble and hesitation!
Here is my experience. I had the hesitation and stumble problem. 991.1 4s. Stumble at around 2500 rpm even on the cruse control. On our cars there are 4 solenoid. 2 for the cams and 2 for the valves. I changed 1 cam and 1 valve cylinder 4-5-6. PROBLEM FIXED!! Have these solenoid checked I'm sure that's the answer to the stumble and hesitation!
Peace
Bruce in Philly (now Atlanta)
#32
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Initially I had no error code only hesitation and stumble around 2500 rpm with a very slight demand for power. I had two check engine episodes (in one year) with the codes P2103 and U0418 but they cleared on their own after a few kilometers. Then the stumble increased and I had several 4-5-6 side missfires. My mechanic interchanged the cam solenoids and the problem went to the 1-2-3 side. The problem was 80% resolved but there was still something to be resolved. So he changed the lift valve solenoid and it's perfect. It seems that the two solenoid work in complementarity and that one can work for the other. In my case, both were to be changed ... I believe that the solenoids can be checked by manipulating them ... They should make a noise confirming that they are not obstructed.
Last edited by __ Charley __; 09-02-2021 at 10:44 PM.
#33
RL Community Team
Rennlist Member
Rennlist Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Initially I had no error code only hesitation and stumble around 2500 rpm with a very slight demand for power. I had two check engine episodes (in one year) with the codes P2103 and U0418 but they cleared on their own after a few kilometers. Then the stumble increased and I had several 4-5-6 side missfires. My mechanic interchanged the cam solenoids and the problem went to the 1-2-3 side. The problem was 80% resolved but there was still something to be resolved. So he changed the lift valve solenoid and it's perfect. It seems that the two solenoid work in complementarity and that one can work for the other. In my case, both were to be changed ... I believe that the solenoids can be checked by manipulating them ... They should make a noise confirming that they are not obstructed.
Peace
Bruce in Philly
Last edited by Bruce In Philly; 09-03-2021 at 12:17 AM.
#34
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
When my vvs went I had misfires on 1,3,5 cylinders as the solenoid was stuck in the high rev position and did not return back to the idle position. The car idled like crap but ran fine above 2500rpm.
#36
Instructor
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Same question again - does anyone know what value to watch in Durametric / PIWIS to check how well the Cam sensor / solenoids are working?
I am getting codes where the entire bank 2 is running rich and stumbling at idle - wonder if this might be the VVS having trouble with a bad sensor or solenoid
I am getting codes where the entire bank 2 is running rich and stumbling at idle - wonder if this might be the VVS having trouble with a bad sensor or solenoid
The following users liked this post:
Ducaiti999 (03-10-2022)
#37
RL Community Team
Rennlist Member
Rennlist Member
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Same question again - does anyone know what value to watch in Durametric / PIWIS to check how well the Cam sensor / solenoids are working?
I am getting codes where the entire bank 2 is running rich and stumbling at idle - wonder if this might be the VVS having trouble with a bad sensor or solenoid
I am getting codes where the entire bank 2 is running rich and stumbling at idle - wonder if this might be the VVS having trouble with a bad sensor or solenoid
I don't know how to check the Durametric for lift actuation. I have read that any failure of these will throw a code. Beyond that, I can't help.
Peace
Bruce in Philly (now Atlanta)
#38
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I replaced the actuator VVS to no affect. It is stupid easy to do... they sit one on each bank next to the spark plugs. Just plug and play.
I don't know how to check the Durametric for lift actuation. I have read that any failure of these will throw a code. Beyond that, I can't help.
Peace
Bruce in Philly (now Atlanta)
I don't know how to check the Durametric for lift actuation. I have read that any failure of these will throw a code. Beyond that, I can't help.
Peace
Bruce in Philly (now Atlanta)
Question. I've been driving myself crazy trying to figure this out. Do you have the part number for the VVS you changed? Location on the engine? And as I understand it this solenoid does NOT require locking the cam. Is that correct? The other solenoid does require locking the cams?
Just to confirm. These are the solenoids not the cam sensor? I did swap my cam sensors, they are located in the valve cover next to the plugs. I thought the solenoid was on top of the head.
Thanks in advance
Last edited by Ducaiti999; 03-10-2022 at 11:40 PM.
#39
RL Community Team
Rennlist Member
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Question. I've been driving myself crazy trying to figure this out. Do you have the part number for the VVS you changed? Location on the engine? And as I understand it this solenoid does NOT require locking the cam. Is that correct? The other solenoid does require locking the cams?
Just to confirm. These are the solenoids not the cam sensor? I did swap my cam sensors, they are located in the valve cover next to the plugs. I thought the solenoid was on top of the head.
Thanks in advance
Just to confirm. These are the solenoids not the cam sensor? I did swap my cam sensors, they are located in the valve cover next to the plugs. I thought the solenoid was on top of the head.
Thanks in advance
![](https://cimg2.ibsrv.net/gimg/rennlist.com-vbulletin/1348x247/screenshot_20220310_225714_gmail_4d8de49cb6290dbf63eabd76829c6802c5b4b7ea.jpg)
The following users liked this post:
Ducaiti999 (03-11-2022)
#40
#41
RL Community Team
Rennlist Member
Rennlist Member
The following users liked this post:
Ducaiti999 (03-11-2022)
#42
#43
RL Community Team
Rennlist Member
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Sorry, I confused you. You only need to lock the cams when replacing the timing chain tensioners. You don't have to lock the cams when replacing these variocam actuators. Just unscrew them and replace.
The following 2 users liked this post by Petza914:
Ducaiti999 (03-11-2022),
Floyd540 (03-12-2022)
#44
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I really appreciate your insight here.
Thanks again
#45
RL Community Team
Rennlist Member
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Good news there. Im amazed at how hard it is to get information on this. I assume the 991.1 engine is the same situation. I've done just about everything else. Except variocam solenoid and injectors. My idle stumble is definitely getting worse and my bank 2 fuel trims are being wacky. For all the tech in this car it's amazing this idle issue affects so many units and no clear way to test for possible defective parts.
I really appreciate your insight here.
Thanks again
I really appreciate your insight here.
Thanks again
Check your bank 1 and bank 2 camshaft deviations too. Variability there is more likely the variocam solenoids.
The following users liked this post:
Ducaiti999 (03-11-2022)