Took a Durametric capture last Sunday

[l3m]

I have a 2001 with a 3.2L engine. The car had 28K on the odometer when the engine was replaced in Sept. 2005. The car was at 30K when I purchased it in Sept 2011 and has had 3 oil changes since then. The car now has 42K. I'm guessing I have the dual row bearing but with a remanufactured engine, I can't be certain.

I purchased a Durametric recently and started researching about camshaft deviation values. Basically the message I got was as long as the idle values are steady, that means the IMSB is ok. Also, the difference between cam 1 & 2 should be +/- 6.

Last Sunday I attach the Durametric and start the car. I let it idle for about 10 mins. then I head out on the road. I take surface roads and drive under 3000 rpm for 20-30 mins. until I feel the engine is warmed up properly. Then it's all freeway speeds and occasional bursts over 4K rpm until I get home. I drove for 1 hour. I graphed the cam 1/2 values and posted the graph below.

As you can see cam2 is mostly steady at 0.34 and going up slightly to 0.36 in the last 10 mins.

For cam1, it starts at -4.44 then decreases to -5.23 while the car is still idling. I remember leaving the house and seeing -5.23 on the durametric screen. It stays at -5.23 for 14 mins then starts creeping back up. When I'm nearing home, it finally settles at -4.64 and stays steady until I turn off the engine.

Why would the car start at -4.44 and suddenly jump to -5.23 during warm-up? Is there any reason to be concerned about these changing values? Any input would be greatly appreciated.

[san rensho]

For what its worth, I get similar results. Bank 2 is always very steady and hardly changes cold to hot, bank 1, on the other hand, goes from about -6.3 cold, to -5.5 hot. My understanding is that when you have variations at idle over the short term then that could be a sign the IMSB is failing.

[l3m]

Originally Posted by san rensho

For what its worth, I get similar results. Bank 2 is always very steady and hardly changes cold to hot, bank 1, on the other hand, goes from about -6.3 cold, to -5.5 hot. My understanding is that when you have variations at idle over the short term then that could be a sign the IMSB is failing.

That's good to know. I wasn't sure if the values were supposed to be consistent hot or cold. This 1st time I used the tool I only used it for 10 minutes. I was seeing the values change on bank 1 and 2 during idle and it got me worried.

[Topless]

Consider this a baseline and your car is within factory tolerances so no worries. Check it again after each oil change and note any sudden unusual differences.

I have said this before but more ulcers and heart conditions have been caused by staring at a Durametric screen than actual IMS failures.

[com3dorm3]

Originally Posted by Topless

I have said this before but more ulcers and heart conditions have been caused by staring at a Durametric screen than actual IMS failures.

Hmm. I've never used this tool. I'm wondering if this is the case of "ignorance is bliss"??

[jaykay]

What is the sample time? The time scale the top is hard to see. This might be reasonable if the sample time is long. mine are always flat lines but I am looking at 3-5 min at most

Experts?