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Old 11-30-2010, 02:16 PM   #1
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Maurice, that line from the top of the oil cooler is a vent to the surge tank to release entrained air from the cooler, which happens to be the highest point of the cooling system on the engine. By getting rid of the air, the laminar flow exchanger works very well; with trapped air, its thermal efficiency falls off very quickly....
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Old 11-30-2010, 02:19 PM   #2
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Quote:
Originally Posted by JFP in PA
Maurice, that line from the top of the oil cooler is a vent to the surge tank to release entrained air from the cooler, which happens to be the highest point of the cooling system on the engine. By getting rid of the air, the laminar flow exchanger works very well; with trapped air, its thermal efficiency falls off very quickly....
JFP:

Thanks again for your invaluable input!

It's always appreciated.

Regards, Maurice.
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Old 12-01-2010, 02:29 AM   #3
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Awesome project, I'm really interested in what kind of real world performance it will put down
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Old 12-01-2010, 04:34 PM   #4
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okay, i hit it with a code reader today......no codes. another oddity is that even though i'm using the RoW program which should only monitor two O2 sensors, i'm getting readings from all four.....

so, here are some numbers at idle:

MAF: 0.95
Ign Adv: 12deg
Fuel Sys 1 & 2: closed
ST Ftrm 11: -11.7%
ST Ftrm 21: 9.4%

the symptoms are a lumpy idle and a very fuel-rich exhaust with some smoke. from the numbers above, it seems that one bank is rich & one is lean.....

i will work on prepping a diagnostic plan tomorrow. in the meantime, any ideas are welcome! as a first order of business, i will check to see if the small oil leak from the area of the #1 spark plug tube is somehow related.
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Old 12-01-2010, 08:05 PM   #5
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Quote:
Originally Posted by insite
okay, i hit it with a code reader today......no codes. another oddity is that even though i'm using the RoW program which should only monitor two O2 sensors, i'm getting readings from all four.....

so, here are some numbers at idle:

MAF: 0.95
Ign Adv: 12deg
Fuel Sys 1 & 2: closed
ST Ftrm 11: -11.7%
ST Ftrm 21: 9.4%

the symptoms are a lumpy idle and a very fuel-rich exhaust with some smoke. from the numbers above, it seems that one bank is rich & one is lean.....

i will work on prepping a diagnostic plan tomorrow. in the meantime, any ideas are welcome! as a first order of business, i will check to see if the small oil leak from the area of the #1 spark plug tube is somehow related.
Insite:

I know that you have dealt with the common issue of the correct volume/velocity of the air intake as affected by the diameter of the intake housing/tubing by installing the BMW 540i MAF housing and the associated silicone tubing, but are you sure that all of that is correct and that there are no air leaks anywhere in the tubing connections?

Also, is it possible that the DME has to learn the values by going through the various cycles, as it does when you disconnect the battery for a while and the DME has to relearn the correct fuel trims, etc.? And that may one of the causes for the lumpy idle?

Regards, Maurice.
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Old 12-02-2010, 04:47 AM   #6
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maurice - all good puts.

since i have an oil leak and it's the first obvious point of breach from the engine internals to the environment, i'll look there first for vacumm leak issues. once i resolve that, i will pull the plugs & examine each to try & pinpoint the issue to a single cylinder, single bank, or all cylinders / all banks.

your MAF questions are good. looking at my ST FTRM readouts, you'll notice that once cylinder is trying to lean itself & the other is trying to enrich itself. if the MAF were the issue, we'd see similar rather than opposing trends between the banks. looking at these numbers, my guess is that if i allow the engine to run a bit longer, the adaptation will eventually move me out of the 'normal' range and i'll get a 'LEAN LIMIT' code, meaning that the engine is running too rich for the DME to compensate. i will, however, disconnect the MAF & give it a test run just in case.

the next order of business will be to check for vacuum leaks. i'll do this with propane & a visual / audible inspection.

hopefully by the time i get to this point, something will be obvious. if not, i will need to revalidate the camshaft timing. i'm positive i verified it as spot on prior to putting the enigine in the car, so i bet we'll find the problem before we get here.....

in the meantime, here are a few more photos of the installation:

engine bay:







airbox (i will add a hose to the airbox inlet that elbows over to the body inlet to ensure cold air only):





close-up of the too-tall tranny mounts:

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Old 12-02-2010, 05:20 AM   #7
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What Maf housing are you running?
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