Possible Indicator of Impending IMS Failure

[986Shaft]

Just thought I would post this information, in case it helps anyone avoid an IMS failure.

Leading up to our blown engine, the car had a slight hesitation in 2nd gear, low-to-mid rpms. I took this to be a fuel injector problem. In fact, we ran some fuel injector cleaner through the car on that fateful day.

I can't be sure, but it seams like the IMS failure occurred at about the same gear/rpm range where we had been experiencing the hesitation. The engine failed as we accelerated away from a stop light, probably at about 28-30 mph - this is roughly where we had the hesitiation.

The argument against this being an indicator is that I actually thought that the fuel injector cleaner had done the trick... earlier in the day the hesitation seemed to have gone away.

Has anyone else who has experienced an IMS failure had a similar experience?

(2003 Boxster S, still sitting in the garage....)

[2K3_Boxster_S]

Originally Posted by 986Shaft

Just thought I would post this information, in case it helps anyone avoid an IMS failure.

Leading up to our blown engine, the car had a slight hesitation in 2nd gear, low-to-mid rpms. I took this to be a fuel injector problem. In fact, we ran some fuel injector cleaner through the car on that fateful day.

I can't be sure, but it seams like the IMS failure occurred at about the same gear/rpm range where we had been experiencing the hesitation. The engine failed as we accelerated away from a stop light, probably at about 28-30 mph - this is roughly where we had the hesitiation.

The argument against this being an indicator is that I actually thought that the fuel injector cleaner had done the trick... earlier in the day the hesitation seemed to have gone away.

Has anyone else who has experienced an IMS failure had a similar experience?

(2003 Boxster S, still sitting in the garage....)

Ok, thanks for this post. I had a some hesitation in First gear the other day. Now im driving around with my butt cheeks clinched waiting to catch the infamous N1 H1 IMS Failure . Great. did it feel like a complete fuel cut for just a split second?? then never happen again?

[Jake Raby]

The symptom mentioned is isolated from the IMS.. When an IMS bearing gets bad enough to cause a hesitation, your pistons have already collided with your valves at maximum velocity and the engine looks like 3 mile island internally.

[986Shaft]

The hesitation we had seemed to mainly occur in 2nd gear, and I took it to be a fuel injector problem. I posted the information because it was the only mechanical issue we noticed prior to IMS failure.

Jake sounds certain that a failing bearing wouldn't cause such a hesitation, so I guess it's not an indicator for the IMS bearing.

[23109VC]

Are u gonna fix your car? Stock or upgraded motor?

[spine911]

Originally Posted by Jake Raby

The symptom mentioned is isolated from the IMS.. When an IMS bearing gets bad enough to cause a hesitation, your pistons have already collided with your valves at maximum velocity and the engine looks like 3 mile island internally.

+1...Fuel delivery issues will have no effect on the integrity of the IMS- just a bad coincidence.

[986Shaft]

Originally Posted by 23109VC

Are u gonna fix your car? Stock or upgraded motor?

Don't know yet. It's my wife's toy, and I figure it (was) already to fast for her...we don't need a 100+ (mph) ticket. So probably stock (still plenty to get that ticket).

Unfortunately, options are all expensive (bought the car for $20k)

~$13,500 through Porsche (with clutch and 2 yr warranty). We've been turned down for any assistance from Porsche at this point, but have asked again - thought maybe if we had them fix it, they could at least forgo making a profit on the engine.

~I think a bit more from Jake Raby, and we're on the wrong side of the country - his warranty requires installation in Georgia (as I understand it)

~maybe $9-10K for a used engine. Doesn't seem like a good option, because we're afraid of losing another one, and it's not that much cheaper than Porsche with a warranty.

Ruff upgrade - I'm not close to that league

Sell it - probably lose as much or more than if we fix it.

It was fun to drive when it ran, and my wife want's it back. I suppose that means we'll fix it.

Oh well, my Vulcan still runs

[986Shaft]

Originally Posted by spine911

+1...Fuel delivery issues will have no effect on the integrity of the IMS- just a bad coincidence.

I didn't think a fuel delivery problem was affecting the IMS.

I don't know the specifics, but recall reading that the Intermediate shaft is under the most stress at lower RPMs, in lower gear. Supposedly why failures seem to happen at low speed, e.g. accelerating away from a stop light (as in our case). If this is true, I wondered if there was enough resistance at this point to cause the engine to hesitate.

From subsequent posts, it sounds like experts think this would not occur. If so, the hesitation probably was a fuel delivery problem, and not related the IMS problem. I just found it odd that it only happened in a certain RPM range in 2nd gear.

[Jake Raby]

I think a bit more from Jake Raby, and we're on the wrong side of the country - his warranty requires installation in Georgia (as I understand it)

Correct.. For an engine of mine to receive full warranty it must be installed by the same team that designed and created it..

But don't get stuck on a piece of paper.. That piece of paper doesn't mean much at all and won't do anything to increase the durability of the engine.
I have chosen to put my effort into the development of a well built, updated engine rather than having a team of Lawyers come up with documents with small print that are virtually worthless..