996 intermediate shaft problems

[Loren]

Now, a few weeks preceding this event, an intermittent, muffled clanking noise (hmm... like a nylon screw rattling around in a coffee can?) could be heard when inspecting an idling engine. It was sometimes difficult to hear, and sometimes the noise would cease for periods longer than a day. I do not hear this noise on my rebuilt engine, so perhaps this was the indicator. I monitored (but somewhat disregarded) this noise because it is often trumped by my ticking lifters, automatic fans, etc.

ADVICE: if you hear a similar sound, don't hesitate to take the car to an indie and inquire about this problem and preventive remedies, but note that this clanking is intermittent and is not the same as the periodic ticking noise often encountered in an old hydraulic lifter.

so it was a rattle and not a ticking.... and it did not increase in frequency i.e faster rattling or more tapping as the engine revs increased? hmmm... maybe we have a bad lifter instead?

When an intermediate shaft goes it (or one of it's bearings) the car will sound like a bucket of bolts and it usually happens all at once (i.e. no warning).

[togilvie]

deleted

Edited March 29, 2012 by togilvie

[c70Pete]

C70pete and Loren,

Yes, it was intermittent rattling and not a ticking. Also, it did not increase in frequency with RPM increase (although it would be very difficult to hear the rattling over a revving engine). It sounds like the intermittent rattling may not have been caused or related to the IMS failure; it's the only unusual sound I noticed, so I guess I came to that conclusion after the fact. However, if I ever hear that sound again, I'm going straight to the mechanic. The car was absolutely silent when it failed and would not start again. I didn't observe the "bucket of bolts" sound at any time preceding or following failure. Hmmm.

Togilvie,

that's good to know.... I have a ticking and we believe it to be something lose on the exhaust manifold a bolt or so... that ticks with each exhaust pulse... were hoping its that... otherwise were looking at a bad lifter? it ticks faster as rpm increases.... its going to the shop this weekend so I'll let you guys know what we found....

[lmurthwaite]

C70pete and Loren,

Yes, it was intermittent rattling and not a ticking. Also, it did not increase in frequency with RPM increase (although it would be very difficult to hear the rattling over a revving engine). It sounds like the intermittent rattling may not have been caused or related to the IMS failure; it's the only unusual sound I noticed, so I guess I came to that conclusion after the fact. However, if I ever hear that sound again, I'm going straight to the mechanic. The car was absolutely silent when it failed and would not start again. I didn't observe the "bucket of bolts" sound at any time preceding or following failure. Hmmm.

Togilvie,

that's good to know.... I have a ticking and we believe it to be something lose on the exhaust manifold a bolt or so... that ticks with each exhaust pulse... were hoping its that... otherwise were looking at a bad lifter? it ticks faster as rpm increases.... its going to the shop this weekend so I'll let you guys know what we found....

I'm very interested to hear what the result of your garage vist was. I have the same problem. An intermittent ticking noise that sounds like a knocking camshaft or tappet. It happenes usually after I have given the car a bit of a spank on the motorways and it tends to happen to either side of the engine just behind the rear wheels. I'm certain it's a lifter or some sort of oil starvation. I have a 98 C2 Tip 3.4l.

[c70Pete]

C70pete and Loren,

Yes, it was intermittent rattling and not a ticking. Also, it did not increase in frequency with RPM increase (although it would be very difficult to hear the rattling over a revving engine). It sounds like the intermittent rattling may not have been caused or related to the IMS failure; it's the only unusual sound I noticed, so I guess I came to that conclusion after the fact. However, if I ever hear that sound again, I'm going straight to the mechanic. The car was absolutely silent when it failed and would not start again. I didn't observe the "bucket of bolts" sound at any time preceding or following failure. Hmmm.

Togilvie,

that's good to know.... I have a ticking and we believe it to be something lose on the exhaust manifold a bolt or so... that ticks with each exhaust pulse... were hoping its that... otherwise were looking at a bad lifter? it ticks faster as rpm increases.... its going to the shop this weekend so I'll let you guys know what we found....

Togilvie... that's exactly the symptom my car had... I have a 99c2... I think its your bearings ... does it happen on the right rear side of the car? do you still hear the tick as RPM increases or does it go away? what is the mileage of your car....