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Hydraulic oil pressure is proportional to engine rpm,
Not in any linear fashion, it's not. I can't recall if the QP has an oil pressure gauge, but every car I've ever driven with one it's very clear that pressure increases very very much faster than engine revs.

C
 
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Engine oil pressure is not proportional to engine RPM...If you hook a mechanical gauge on a car you can see it...It is low at idle (about 10-15 PSI) and when you bring the revs up to 2k it will raise up to about 40 PSI and stay fairly flat but will raise up slightly more as you reach max revs...It doesn't just match the the tachometer.....Jason
 

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The discussion on the VVT system is in the CAM VARIATOR thread, which postulates on several causes for the expensive variator failures people have experienced. Hydraulic oil pressure is proportional to engine rpm, which is why the transmission mode was considered as a source of the problem in the thread. Re-reading the thread I came to the conclusion that the problem is more likely the mounting orientation of the accumulator causing uneven seal wear, then accumulator failure is not diagnosed until the variator failure recurs as the new parts wear out a second time. It also seems to affect the Dry Sump systems far more than the later Wet Sump systems. It's a long thread, but the issue seems to be a problem a number of owners have experienced. I may still have this wrong, can someone chime in who knows the final answer?

It would help brand new owners like me Jason if you would add in a brief summary of the facts since I was mislead by the discussion in other thread.
You're reading my posts.

I was simply theorizing about reasons why the dry sump units typically fail both bilaterally and repeatedly on the "bad" cars, while others last a lifetime. So, it can either be the driving habits of the owner, or some internal contributing factor leading to bilateral failure. After consulting with the manufacturer of the accumulators and after replacing all the other timing components on my personal car, I strongly believe the accumulator is the weak link.

After 1000 miles, and a complete replacement of everything new, my rattle returned. Other dry sump cars used as daily drivers have had similar issues. One specifically I know of, had the work done at the dealer, has had 3 replacements by 80K miles. The only part the dealer failed to replace was the accumulator.

The accumulator works to keep high pressure consistent throughout hydraulic usage cycles, temperatures, etc. Think of it as a water tower in a community water system. Without it functioning properly, the entire community will have low pressure, not just one or two houses.

I now have two QPs to work with over here and by the process of elimination we plan to take the time to replace one part at a time until the issue is resolved. The parts are here, but I do have a day job so hopefully we will start on this next weekend and report back to ML with results.

Sorry for the off-topic response, but as the OP, I need to clarify to avoid further confusion.
 

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Ok we're getting off topic here... lets get back to what Maserati owners are really concerned about...
Gas mileage!

Worst thread ever! lol
I know I bought my QP V Duoselect, after reading the 10 MPG reviews in the car magazines, clearly with mileage in mind. I was trying to buy the car with the worst mileage I could afford. A 1986 Lamborghini Countach has like 7 mpg but too rich for my blood... so the QP V was a compromise....
 
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