3.4L Motor Swap Underway!

[schoir]

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.

[insite]

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:

[JAAY]

What Maf housing are you running?

[insite]

Originally Posted by JAAY

What Maf housing are you running?

it's the 3.5" housing from a BMW 540i (E39). i believe it was your recommendaton, & it does match the 996 3.4L diameter. still, if the MAF housing were my issue, i think i'd be reading rich at both banks......

[JAAY]

Never mind. I missed the 540 post. Sounds like a vacuum leak. I had issues like this right after I did my 3.4 also. I just had leaks in the intake system and on the intake manifolds. I hope you get it all ironed out.

[insite]

Originally Posted by JAAY

Never mind. I missed the 540 post. Sounds like a vacuum leak. I had issues like this right after I did my 3.4 also. I just had leaks in the intake system and on the intake manifolds. I hope you get it all ironed out.

you're probably right......we shall see.

[insite]

ok, some progress:

oil leak diagnosed. i remember now i had waited to tighten the oil pressure sender because i didn't have a narrow enough wrench to get between the head & the sender. no worries; channel locks worked wonders.

funny noise diagnosed. the power steering lines were still cavitated. i turned the steering back and forth a bit, topped off the fluid, and it quited down.

drivability issue diagnosed. i pulled the plugs; all looked well. i checked for vacuum leaks; all looked well. it SEEMED like a cam timing issue to me, but i got a feeling it would work itself out. this motor was degreased & shelved for EIGHT years. when i did a compression test before i installed the motor (turning it by hand), some cylinders didn't have very good readings. i've been working under the assumption that some scaly crud was preventing the valves from closing all the way & maybe interfering w/ the lifters. anyway, i let it run for awhile. i revved it up to 4k and held it until everything was good and hot. i blipped the throttle a bunch & generally tried to blow out the junk. sure enough, it smoothed out & the fuel adaptation values converged. everything is looking good!

saturday, i'll raise the transmission 1/4", then put the axles & suspension bits back in. then it will be time for a road test. booyah.

[Pat]

All good news. You've got to be SO jacked by now to get that thing on the road. VERY exciting stuff!
:dance: