Multiple failures all fixed - but still running too hot?

DaveAU335i

New Member
Sep 4, 2018
4
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2008 E93 335i
Hi,

The car is 100% stock, aside from a K&N air filter. KM at time of purchase 136K. Current KM 166K.

Long story short, dealer misrepresented the car with fake information, and bogus paperwork. Worse, since purchase I've had nothing but drama. I've replaced just about everything in the motor that fails, which has failed over the last 30,000km.

My major concern right now is the motor reaches oil temps verging on the limp-mode threshold...127C (260.6F) - 129C (264.2F). Not that it's gone into limp-mode, but when it starts hitting around 123C the turbos start acting up (spluttering) and power starts to degrade.

NB - Oil and filter is changed between 5,000 - 6,000km (Fuchs 5W - 40).

I'm not really tech minded or skilled, instead have all mechanical work done by firstly BMW dealer (electric water pump), followed by a number of indy shops.

Below is what's failed and been fixed. Approx KM's.
  1. Electric water pump (failed 3 days after purchase). Replaced, including new thermostat. Injectors on recall replaced.
  2. 141K - Oil filter housing etc., 3x flushing, 2x oil filter's clogged (oil sheered - akin to black treacle). Plugs were also replaced.
  3. 10 days later PCV clogged with sludgy oil residue. New replaced.
  4. 145K - radiator reservoir tank seal split. Replaced and lines too. Turbo reservoirs also replaced. Sump gasket also found leaking oil, fixed.
  5. 147K - Salmon relays (2x) convertible roof electrics.
  6. 150K - High pressure fuel pump, replaced and fixed.
  7. 153K - brakes and front steering rod (?) bushes replaced.
  8. 159K - Radiator leaks, replaced with new unit, and hoses etc. Also, intercooler (broken clamp?) 1 of the pipe's was barely holding. Fixed.
  9. 165K (August 2018) - coolant weeping from turbo lines. All 4 lines replaced etc.
I've spent close to AU$20K getting all this fixed, yet I've still got this blasted oil temp issue. One thing I've noticed, the radiator fan(s?) are running BUT no longer hit max-speed mode.

I live in the country, and on highway travel 110km/h and the oil temp (if I don't gun it) sits around 105 (221F) - 110C (230F). If I do happen to hit boost, it rises quickly, but then does cool back down when no boost. Though, I'm guessing the cool air at 110km is enough to do that.

However, as soon as I start driving the car hard (with boost, lets say for a 5 min period) the oil temps raise to 120C+ and soon they are peeking 127C (260.6F) - 129C (264.2F).

It's going to BMWise Adelaide next Monday, to see if they can nut out what the issue is.

But in the meantime, given members here seem to be clued up on the N54 335i, thought I'd ask for some input and feedback as to what maybe the issue here?

Any and all assistance is most greatly appreciated :)


Cheers

Dave
 
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tisdrew

Corporal
Jun 27, 2017
175
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09 335i 6MT
N54s run hot (210-230 is normal) by nature since oil runs through the turbos and partially cools them in addition to the coolant lines.

Does it have the factory oil cooler? If not, that's something worth retrofitting. See the link below for a simple method to determine if it has the cooler (with pictures!) Additionally, you can try this out:

http://www.burgertuning.com/sport_oil_cooler_valve.html
 

DaveAU335i

New Member
Sep 4, 2018
4
0
0
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2008 E93 335i
Thanks for the advice, tisdrew.

With 230F (110C) being the max oil temp, clearly mine running at an average of 248F (120C) there's an issue. Yes it does have a factory oil cooler. I'll order this valve, fingers crossed it will help lower oil temps.

Cheers
 

tisdrew

Corporal
Jun 27, 2017
175
87
0
Ride
09 335i 6MT
230 isn't the max oil temp. At some point in 2008, they changed the oil temp gauge in the cluster.

I couldn't find european/celsius examples, but here are the Farenheight ones attached.
 

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matreyia

Major
Apr 19, 2017
1,748
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335i e93
Thanks for the advice, tisdrew.

With 230F (110C) being the max oil temp, clearly mine running at an average of 248F (120C) there's an issue. Yes it does have a factory oil cooler. I'll order this valve, fingers crossed it will help lower oil temps.

Cheers

Your normal temps should be 250F. Especially in summer. If you have stock oil cooler. If you don't have oil cooler then that is why you're too hot.

I have Dinan oil cooler and mine is at 238F normally. On hot days it hits 248F.
 
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