[Coltenxxx]

Hello all, new to the forums so hopefully I don't get too much hazing if I violate any rules of posting. But I purchased an 07' 335I coupe back in January. Had 104,000 miles on it. I figured I'd be nickel and dimed as with buying any vehicle with miles on it. But it had a previous Cobb tune, aftermarket downpipes with secondary cat delete, and unknown after market clutch. Shortly after getting the car from the dealer, my clutch went out. Had it replaced by bmw with a spec stage 3+ clutch and stock dmfw. Drove fine for a few thousand miles until I got my JB4 tuner, bms dci, bms cdv, rb pcv valve, bms occ, 2step nls relay, and maybe a few other goodies I forgot. I installed all this aftermarket over the course of 108,xxx till about 116,000 when things started getting hairy. Started noticing excessive oil consumption, no leak. Burned out the exhaust occasionally. Didn't last long and wasn't bit clouds. Maybe a few times a week. So I redid the valve cover gasket, new plugs, replaced most the pcv components, and added the occ. Also had oil leaking down front of the block so I replaced the oil filter housing and oil cooler gaskets. Helped a little with masking smoke but internal oil consumption continued. Burnt a quart maybe around every two weeks. Turbos sound healthy and boost gauge doesn't show boost oscillation or spiking. Consistent boost. I also redid the vacuum lines in the engine bay, so no problems there. Anyways, around 120,xxx I've had two serpentine belts go out within 4,000 miles. Both new.. replaced tensioner, pulleys and belt. Subframe wasn't scuffed up too bad. But after the second belt replacement I start the car and discover a slight coolant leak. Got worse real quick, so I replaced the water pump and thermostat. Hoses seemed decent. Start car after bleeding it and it still leaked somehow. Took too a so so indy in Meadville PA asking for a leakdown test and the leak fixed since I couldn't trace it and was sick of pissing with it. They discover a hose connection came loose and popped off. They reconnected the hose, refill coolant and tell me no leaks and car is fine. I drove it about 3 days and my low coolant light came on. Topped it off with about 1/3 gallon and drove home. It's happened about 2 times since then. Low coolant light pops on after maybe 60-80 miles of driving and I can smell it while driving. You can smell coolant in the exhaust and in cab sometimes while driving. So any advice on what could be wrong with oil consumption and coolant loss would be appreciated.. oil loss is about 1/8th of a quart every 50-70 miles. not always consistent oil loss. Driving slow, and coming to stops can normally smell oil burning in car cab. Also while pressing accelerator, and during shifts occasionally get blue clouds of smoke. Especially when revving hard. Coolant is same way and loss is about full reservoir tank every 50-200 miles. Varies.

[MrSmileyDC]

Blown head gasket possibly?

[Coltenxxx]

I'm praying that's not the case. I mean the car drives perfectly fine. Boost is great, acceleration is fine. AC works great, doesn't overheat one bit runs around 210° and it's winter time here. When I changed my oil, about 400 miles before coolant leak started, wasn't one bit milky, just black. So I have no clue.

[elons335i]

http://www.walmart.com/ip/48650364?w...546754&veh=sem

[elons335i]

On a somewhat unrelated note. When my old Subaru blew both gaskets it burned coolant internally and leaked oil externally so the coolant leak was very had to trace. The bleed down test showed a functioning radiator that held pressure.

I had a similar test done at a shop to confirm the leak. Also check your overflow tank, I've seen a few guys here talk about replacing those due to cracking.

[Coltenxxx]

Would I be better off calling the local Indy and asking if they do UV leakdown test or should I get both a leakdown and compression test done? They thought oil consumption could've been from rear turbo seal. But I'm more worried about coolant than oil currently

[jauloz]

pull ur downpipe and see if there is excessive oil in the dp/turbo.

PS. you need to learn how to press enter to create spaces. it hurts my eyes to read.

[MrSmileyDC]

There are gaskets on the oil and coolant feeder lines to the turbos. There is also a partially plastic coolant line that runs across the front of the subframe that could be cracked.

[MrSmileyDC]

Originally Posted by elons335i

On a somewhat unrelated note. When my old Subaru blew both gaskets it burned coolant internally and leaked oil externally so the coolant leak was very had to trace. The bleed down test showed a functioning radiator that held pressure.

I had a similar test done at a shop to confirm the leak. Also check your overflow tank, I've seen a few guys here talk about replacing those due to cracking.

Is the bleeder valve closed?

[Coltenxxx]

Yes the bleeder valve was closed. And to he who was offended by my lack of spaces through out that post. I typed the whole thing on a tiny touch screen phone being auto corrected every other word. So my apologies if it wasn't the most appeasing thing to read.
But I will check the dp when able too and that line spoken of. Thank for feedback y'all. It'll probably be a couple weeks before I can give an update.