Idle Rattle Plus Major Overhaul - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Daniel R · 04-22-2012, 10:35 PM

My car (MY2000 S) is currently laid up in the garage owing to me not having a driving licence until the end of June (long story).

I have decided to use this time to put everything right with it that has suffered from my neglect/lack of time/laziness over the years.

The most important thing I want fixed is an engine rattle at idle. I am not sure where it is coming from, it is not a start-up noise, it is permanent when idling either warm or cold. The AC increases the noise as it is a load on the engine, and being in neutral or gear, clutch in or out makes no difference so I assume it is not transmission. Chain tensioners or serpentine belt tensioners?? All advice is appreciated.

The next point of order is to replace any parts that and engine at 120k miles should have replaced. Besides the usual scheduled service items plus spark plugs, is there anything else that could be useful, and in what order of importance?

I would also like to overhaul the suspension at this point, it is getting old and tired. Depending on how much money I have left after shoring up the engine, I will decide to what degree I replace suspension components and with what pieces.

The wife has given me the green light to sell her old car that we no longer use and all the proceeds (between 6 and 7k) will go towards fixing the Porsche, so this is more or less the budget I am working with.

Thanks in advance.

BYprodriver · 04-23-2012, 12:24 PM

Rattle is most likely caused by Chain tensioners start with IMS tensioner & be sure to get the 2002 updated tensioner with the preload spring. Next replace the 1-3 cyl tensioner located on bottom of engine. Once you have installed both pumped full of new oil run engine to see if the rattle is gone & decide if you want to replace the 4-6 cyl tensioner which is much harder since you have to remove A/C compressor to access tensioner. Also listen for lifter noise at this point & decide if you want to replace lifters while doing the Vario-Cam chain wear pads need to be replaced also (4) this requires removing cams, pads could be contributing to noise, good news is they are cheap. IMS bearing & RMS ! You will notice once you have things apart it is fun to replace parts so inspect everywhere & if anything is showing wear buy new parts then. Water pump unless you have replaceed recently, same for motor mount. OK when you can tell us how you lost your license mate!

san rensho · 04-23-2012, 03:05 PM

Quote:

Originally Posted by BYprodriver

Rattle is most likely caused by Chain tensioners start with IMS tensioner & be sure to get the 2002 updated tensioner with the preload spring. Next replace the 1-3 cyl tensioner located on bottom of engine. Once you have installed both pumped full of new oil run engine to see if the rattle is gone & decide if you want to replace the 4-6 cyl tensioner which is much harder since you have to remove A/C compressor to access tensioner. Also listen for lifter noise at this point & decide if you want to replace lifters while doing the Vario-Cam chain wear pads need to be replaced also (4) this requires removing cams, pads could be contributing to noise, good news is they are cheap. IMS bearing & RMS ! You will notice once you have things apart it is fun to replace parts so inspect everywhere & if anything is showing wear buy new parts then. Water pump unless you have replaceed recently, same for motor mount. OK when you can tell us how you lost your license mate!

I seem to remember reading that If you switch to the new style tensioners, that you need to replace all of them. I can see where you should replace the IMS and bank 1-3 since they both are on the same side of the IMS. But since the 4-6 tensioner is completely on the other side of the IMS, I can't see how not replacing that tensioner could have any effect.

The Radium King · 04-23-2012, 04:38 PM

before you pull your car apart and spend thousands, check your idler pulleys and auxilliaries. the change with ac engaging suggests something with the belt, not chain ramps, etc., so spend hundreds instead.

landrovered · 04-23-2012, 04:42 PM

and give the exhaust a good looking over, it is commonly a cause of rattles as well. Eliminate all the cheap options before diving in to the motor.

BYprodriver · 04-23-2012, 06:06 PM

Quote:

Originally Posted by san rensho

I seem to remember reading that If you switch to the new style tensioners, that you need to replace all of them. I can see where you should replace the IMS and bank 1-3 since they both are on the same side of the IMS. But since the 4-6 tensioner is completely on the other side of the IMS, I can't see how not replacing that tensioner could have any effect.

The only big change to the chain tensioners is the external spring to help maintain tension on the chain, otherwise there is no need to change them if working properly. I recommend the OP change the easy 2 based on his mileage & budget. The 4-6 cyl tensioner has been "updated" to a lower profile design & I assume this is for increased airflow between it & A/C compressor.

Daniel R · 04-23-2012, 07:36 PM

Thank you for the comprehensive list.

The loss of licence was due to a DD (DUI in US) offence. :-( Unfortunately in Australia the limit is 0.05, lower than in California I believe, and a seasoned drinker is over the limit even when feeling fine. A little unfortunate, definitely stupid, now I am becoming acquainted with public transport.

I am leaning towards replacing almost everything, since I will probably keep this car for a long time. If I was to go all the way and do IMS and RMS would it make sense to do the clutch at the same time? It is still fine for general driving, but it has 75k miles on it since the last change (I am very gentle on the clutch, sometimes I shift without it for fun, crunch free of course).

I replaced the motor mount fairly recently, with a Pedro Race mount. It was brilliant at first, but feels like it deteriorated quickly. I notice if I take off quickly and get some wheel-spin, the engine jumps up and down like it did pre Pedro mount. Is it possible that Pedro's solid mount deteriorated quickly, or could it be that due to it's solid nature it put more stress on the transmission mounts and these need replacing now?

Quote:

Originally Posted by BYprodriver

Rattle is most likely caused by Chain tensioners start with IMS tensioner & be sure to get the 2002 updated tensioner with the preload spring. Next replace the 1-3 cyl tensioner located on bottom of engine. Once you have installed both pumped full of new oil run engine to see if the rattle is gone & decide if you want to replace the 4-6 cyl tensioner which is much harder since you have to remove A/C compressor to access tensioner. Also listen for lifter noise at this point & decide if you want to replace lifters while doing the Vario-Cam chain wear pads need to be replaced also (4) this requires removing cams, pads could be contributing to noise, good news is they are cheap. IMS bearing & RMS ! You will notice once you have things apart it is fun to replace parts so inspect everywhere & if anything is showing wear buy new parts then. Water pump unless you have replaceed recently, same for motor mount. OK when you can tell us how you lost your license mate!

Daniel R · 04-23-2012, 07:42 PM

Quote:

Originally Posted by The Radium King

before you pull your car apart and spend thousands, check your idler pulleys and auxilliaries. the change with ac engaging suggests something with the belt, not chain ramps, etc., so spend hundreds instead.

Thanks.

I will definitely do this, as I think you are probably right about where my particular rattle is coming from.

I am also interested in replacing anything that may be necessary to replace in a motor that has done 120,000 miles, just to give me the peace of mind that I won't have a catastrophic failure due to lack of maintenance.