Finally getting ready to fire up the motor (2008 N14 turbo) after rebuilding and refitting the cylinder head. It's been down for 3 full months while I replaced the burned valve.

While it was apart, I replaced the cooling hoses, water pump, t-stat, water pipe, expansion tank, sensors. Also, the fuel lines, injector seals, vacuum lines, serp belt, tensioner, plumbing & pump for the turbo, etc... Basically, any seal or hose or rubber bit I could lay my hands on got replaced.

Any words of wisdom from the group for the first fire up on this motor. Things to watch out for?

My hopes are that I will fill the fluids, install the new battery, and start the motor up normally. No pages of error codes to chase or take to the dealer to get cleared.

 

i have a question: before you were rebuilding the engine what codes were showing on the scanner?

 

When driving, the car stumbled, ran rough, and went down on power. Idle was rough. Warning triangle with "!" was in red, CEL was on constant.

Got it towed to the nearest dealer (Saturday).
Dealer didn't specify which codes were there. Just "various faults for misfire in all cylinders"

Problem was isolated to a burned exhaust valve on cyl 2.

 

Double check that all electrical connectors are plugged back in

You could also pour some fresh oil onto the camshafts, and turn the engine over for a few seconds with fuel pump fuse removed to build up oil pressure, and fill the oil filter can.

Or just fire her up.

That's the plan!

Good luck!

a

 

My burned cyl 4 exhaust valve produced the following array of misfire codes:

P2783 Misfire Mult Cyl Error
P2773 Misfire Cyl 1 Error
P277F Misfire Cyl 2 Error
P2777 Misfire Cyl 3 Error
P277B Misfire Cyl 4 Error

There may have been more, but there is no mistaking a 4-cyl engine lumpy idle when it is only running on 3 cylinders.

a

 

You can get someone to hold the inlet turbo shaft with their fingers so the dry bearings on the turbo don't spin till oil pressure is built.

Its not "needed" just a good precaution.

Good luck.

SRW

 

If the new engine didn’t fix the issue the burned valve was probably just a symptom of another root cause since you are still seeing similar problems. My guess is that you have a blocked catalytic converter due to the lower tension piston rings, a failed pressure seal in the turbocharger, or if your engine had high mileage you could have excessive crank case blow by. These three items contribute to an oil contaminated or blocked catalytic converter since some of the oil can pass through the combustion chamber un-burned.

A blocked catalytic converter on a turbocharged car will cause a lot of crazy problems, to many to list here and most are deadly to an engine. This is because the blockage will restrict exhaust flow through the catalytic converter core and pre-cat pressure will build in the exhaust pipe. The exhaust pressure can damage the turbocharger pressure seal (and turbo) and even cause some exhaust will flow into the engine via the turbocharger.

Exhaust is very corrosive and contains particulates that will not only cause premature engine wear it will also gum up the oil. But the worst thing that it does is fill the intake with oil smoke (from the crank case vent) and liquid oil. Both can cause premature valve oil coking (valves coke in 5k miles), oil pooling in the Intercooler (we have seen up to 6qts), pre-ignition, hydro lock, and elevated EGTs. All these items can have damaging results to an engine not to mention they cause really strange problems and the worst thing is that they can cause catastrophic engine and turbocharger failure. The problem they cause have baffled many mechanics and techs prompted unnecessary parts replacements and multiple failures of the same part/s

Anyway if this is the issue you might want to think about getting your catalytic converter and turbocharger refurbished or getting new ones. Otherwise you could end up burning a valve again or worse blowing up your engine. Just don’t use a shop that cleans them with acid because it can degrade the catalytic converter and cause them to come apart or impede there performance. If you want to test for this type of issue put a pressure gauge on the primary O2 sensor and run the car up to full boost pressure in gear (not 2500 in neutral like the exhaust back pressure testers manual says, that is the process for testing for naturally aspirated cars only).

 

Finally got the gift of time and finished the assembly on the N14. (R55 S)

My fears at starting this thing: A leak in the cooling system, A leak in the fuel system, Getting gobs of codes when I try to start it up.

Last few steps to complete- Cobbled together an expansion tank cap with a hose so I could pressure test the cooling system. Held pressure for several hours while I was busy reassembling other bits. I adjusted the headlight housings so the bonnet would close and latch properly. (It's looking like a MINI again.) Filled the oil, then filled the coolant, and connected the fresh battery (left the neg lead loose in case of a quick shutdown).

My wife arrives home, I ask her to witness.
First attempt- Engine spins, but no start. This was expected- the fuel system was completely dry.
Second attempt- Engine spins, no start, but there was one "almost" in there.
Let the car sit for a few minutes, top off the coolant that has now moved into the motor.
Third attempt- Engine spins, and we have lift off. Wife claps and squeals with joy now that her car lives again.

Let it run for a few minutes, top off the oil and the coolant then shut down.
The only items of note-
Heard a little knocking- topped off the oil and it went away.
Have a yellow check engine light on the speedo console. Will need to read codes. (Time to buy a GOOD scan system with all the money I just saved)
Noticed some wisps of smoke at the exhaust side- Most likely from the anti-sieze paste I used on all the exhaust fittings.

Now to button it up, bleed the cooling system, and drive it around the block a few dozen times so I can build some trust in my work.