Boxster 986 (1997) Potential IMS failure?

[philalw03]

Hi all,

I was driving my Boxster last Sunday when the car suddenly developed what sounded like a scraping noise from the rear right hand side. I pulled over, left the engine idling and the noise stopped, set off again and the noise started again but then quickly stopped and didn't reappear for the 60+ miles on the journey home. Approx 40 of those miles where motorway miles.

The following morning it took me 3 attempts to start the car, it fired up each time but immediately cut out and would only idle after revving the engine for approx 10 seconds, so I thought it best to go straight to a local Porsche specialist. They were immediately concerned with a faint ticking noise at around 1500RPM and attributed this to a possible timing issue so had the car up on the ramps to listen with a stethoscope and are concerned the IMS bearing is failing.

The durametric showed no faults but camshaft deviation at 0 when idling which in the specialists opinion is something they have never seen!

The results of a compression test are "average at best"

In the last 12 months I've had a new MAF fitted, Idle control valve, Lambda sensor and the vario cam guides replaced.

The specialist has said they can't be certain the bearing is failing without removing the gear box to inspect it but then attempting to remove the bearing could result in it falling into the engine meaning a rebulid. Understandably I'm reluctant to pay someone to attempt to put things right only to make them worse!

Having spoke with another specialist this morning they basically told me that if the IMS bearing is going to fail it will happen instantly and that none of the symptoms I've described can be linked to a failing/failed IMS and that i should keep driving the car.

Receiving such conflicting advice leaves me none the wiser as to what my next move should be, the car certainly isn't worth enough to warrant an engine re build but any help or further advice on here would be greatly appreciated.

Cars mileage is 110,00, also has a small oil leak that I've assumed is RMS but which I'm now thinking could have been the IMS seal.

Thanks in advance, Phil.

[philalw03]

Boxster 986 rough idle.: http://youtu.be/wanvze_k4Tk

I've uploaded a video of me trying to start the car.

[Boxstercol]

I would be checking the oil filter for any sign of metal first. I believe you can drop the oilf filter to check for contamination without losing a huge amount of oil. If there are signs of metal in the filter then possibly IMS related. If not then something else.

I would have thought that if the bearing was on its way out it would have failed by now completely.

Good luck with it & keep us posted on the outcome.

[philalw03]

Thanks for the quick reply. I forgot to mention that the specialist has removed the oil filter and confirmed there where metal particles in it!

I'll update early next week when I collect the car, any further advice in the meantime appreciated..

Thank you.

[thegoose]

anonymous said:

[redacted]

I don't think that's quite correct. The IMS bearing does get noisy before it fails catastrophically. However, you need to be listening to it from under the car whilst it's on a ramp with the engine running to notice (luckily this was the case with mine and it got replaced). Consequently the first most people know anything about theirs deteriorating is when it does let go altogether.

[DAVIDW865]

The IMS on my 2005 987 Bpxster failed about 18 months ago and the chain of events was similar to what you describe - horrible noise which then disappeared and the engine seemed to run ok. Mine also leaked some oil which I only noticed when I got home. I was advised to get a recon engine as that would be cheaper than a repair. We couldn;t find one that was suitable so after a couple of months the engine was repaired with new intermediate shaft. Not much else was damaged though the bearing had broken up. Cost was nearly £5k in the end.

Hartech's website is very informative on the IMS issue.