Hello, I am having some strange issues with a 2008 Saturn Vue AWD with the 3.6L engine. I have been contacting multiple people trying to solve the issue. Below I will copy and paste the email I have sent to someone as it describes the situation in detail. In short we replaced the Timing Chains, Tensioners, Guides, and all 4 Cam Phasers to repair a P0017 code. After repairs and running the vehicle in the shop it set the P0341 code. P0017 code was gone. I found using the scope on a Snapon Zeus that the Bank 1 Intake Cam Sensor Signal had an abnormal pulse in the middle of one of the 2 big pulses. The abnormal pulse was always on the same "tooth" and was not always there, and many times the sensor seemed to miss the tooth completely. Since it was always on the same spot we thought the Phaser we installed may have had an issue so we put another one on with no difference made, I also swapped the cam sensors around. After doing this I realized there was a thin washer that came with the new phaser that had not been installed on the original phaser and did not come with any of the other phasers for the other cams. We removed the phaser and installed the washer just to be sure, at this point I can have it apart in about 10 minutes. After installing the washer the signal did not change much, it seems to very rarely not see the tooth but the glitch in the signal happens frequently. Since installing the shim the P0341 code has not set but it will set a P0300. Since this is the cam that the PCM uses to determine Igintion and Injector Timing the P0300 did not surprise me and the engine seems to run normally. Any ideas would be greatly appreciated as we are out of ideas and even some of our Pro Tech Lines are not sure what else to do.

In the email I copied and pasted below I refer to the scope captures I sent with the email. Here is a Google Drive link to those captures. so you can see the issue I am referring to.
https://drive.google.com/file/d/0B_5...ew?usp=sharing


The vehicle is a 2008 Saturn Vue AWD with the 3.6L engine. Originally it had a P0017 code. We replaced the timing chains with a timing kit. We also replaced all 4 VVT Actuators since we were going to have it all apart. After repair, the vehicle ran great but after running for some time would set a P0341 code. This code was not in the computer before but it did have a P0300 history code stored when it first came in.

While watching the scan data I checked the counts on the cams and found that the bank 1 intake cam active counts were not in sync with the other cams. I decide to scope the cams to be sure my timing was set properly and noticed the issue that is circled in the waveforms I attached. The waveforms are of the bank 1 and bank 2 intake cams. The crank is in some of the waveforms. One waveform has the power supply to the bank 1 intake cam sensor, another has the ground at the sensor.

In the spots I circled I notice the abnormal pulse in the waveform. The captures do not show it very well but this happens intermittently but often enough that it is easy to spot when the scope is live. I also noticed that it seems to occur on the same pulse every time. I swapped the cam position sensor with the exhaust cam sensor with the same result. I also checked the waveform at both the sensor and at the PCM to be sure it looked the same and I did not have a bad wire. The 5 volt reference seemed to remain constant and the ground looked okay.

We then replaced the new VVT Actuator on the Bank 1 Cam thinking that we had ruled everything else out, but the problem was still there. I then found a TSB about an issue with cam shaft end play. I followed the TSB which had me check the end play, I have about .008" end play and the TSB said I should have less then .016".

Before I checked the end play I did remove the VVT Actuator to install a washer that came with the new Actuator but was not previously installed. The original Actuator did not have a washer and the bank 1 intake cam actuator was the only one of the new actuators that came with a washer. The washer fits between the actuator and the camshaft end cap. Service info also did not mention/show the washer. After the washer was installed the waveform still had the abnormal pulse but before it was installed the pulse was completely missing most of the time, like the sensor was not seeing the tooth on the cam.

After this we are completely out of ideas and were hoping that maybe you have seen something similar to this. Any help you may have would be greatly appreciated. Thank you for your time.

This is a weird one.

If it were me, I'd clean up the old parts, put them back on, and see where the issue goes from there . . . at least the old sensors and phasers. Then, if it goes back to the original codes and behavior, measure measure measure, especially where that spacer/washer is concerned.