986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - Need Help with 986 Oil Pump or Timing Chain Rattle

Geo986 · 03-07-2019, 07:31 PM

Hi, my dear friends and Porsche Boxster 986 enthusiast. My son and I have a 1999 Porsche 986 we have rebuilt together and spent some quality hours working on it together. We come to you today because we need your help to diagnose some issues, we are having. We are attempting to diagnose some ECU codes and noises coming from what we believe to be the engine oil return pump on Cyl 4 - 6 on bank 2. That is behind the driver side.
This noise occurs mainly when the car started cold, it lasts for around 4 to 6 seconds, then it goes away. When it is warm it rarely does it. We have read several reports on the particular issue on this site as well as others. One particular point that stood out as a possibility is that it could be a camshaft timing issue in combination with the following ECU Codes. P0341 – Cam Position Sensor 1, P1539 – VarioCam (Apparently), P1117 – Pre-Catalyst O2 sensor heating on Cyl. 1-3. At this point, we are reaching out to people to gain a consensus from your opinions and experiences to better understand what this rattle may be.
My son and I have discussed the matter and researched it thinking that could be several items. The VarioCam actuator or some of timing chain guides could be damage, as well as one or two chain tensioners. In addition, we are getting the following ECU codes. P1121 Throttle Position Sensor 1, P1126 O2 sensing adaptation lower load range Cyl. 1-3. P0410 secondary air injection system Cyl. 1-3. We are not sure if they are related to the problem above since we have changed both cam position sensors.
We're trying to have a better pre-diagnosis due to the cost associated with changing all these parts and the time it will take for it to be done. We have read that it could be done without taking out the engine, however, the valve cover will need to be removed.

Thank you for your replies and comments on the subject.
GeoBen and Son.

03-07-2019, 07:31 PM	#1
Geo986 Registered User Join Date: Nov 2016 Location: Florida Posts: 1	Need Help with 986 Oil Pump or Timing Chain Rattle Hi, my dear friends and Porsche Boxster 986 enthusiast. My son and I have a 1999 Porsche 986 we have rebuilt together and spent some quality hours working on it together. We come to you today because we need your help to diagnose some issues, we are having. We are attempting to diagnose some ECU codes and noises coming from what we believe to be the engine oil return pump on Cyl 4 - 6 on bank 2. That is behind the driver side. This noise occurs mainly when the car started cold, it lasts for around 4 to 6 seconds, then it goes away. When it is warm it rarely does it. We have read several reports on the particular issue on this site as well as others. One particular point that stood out as a possibility is that it could be a camshaft timing issue in combination with the following ECU Codes. P0341 – Cam Position Sensor 1, P1539 – VarioCam (Apparently), P1117 – Pre-Catalyst O2 sensor heating on Cyl. 1-3. At this point, we are reaching out to people to gain a consensus from your opinions and experiences to better understand what this rattle may be. My son and I have discussed the matter and researched it thinking that could be several items. The VarioCam actuator or some of timing chain guides could be damage, as well as one or two chain tensioners. In addition, we are getting the following ECU codes. P1121 Throttle Position Sensor 1, P1126 O2 sensing adaptation lower load range Cyl. 1-3. P0410 secondary air injection system Cyl. 1-3. We are not sure if they are related to the problem above since we have changed both cam position sensors. We're trying to have a better pre-diagnosis due to the cost associated with changing all these parts and the time it will take for it to be done. We have read that it could be done without taking out the engine, however, the valve cover will need to be removed. Thank you for your replies and comments on the subject. GeoBen and Son.