Multiple codes, hunting idle, limp mode

[rtwaits]

Hi All,
I have looked at a 2013 X5 3.5 xDrive with 131,000 miles. I already own a 2012, plus other BMWs. This one starts perfectly, but then almost stalls, and then settles on a surging idle, from about 800-1600 rpm. The owner took it to the dealer, who found brass in the oil filter, which had torn pleats, suspecting work rod bearings or cam journals. I do not know to what extent, though the phrase "clogged with debris" was used. The car itself is very clean, and the dealer said otherwise the engine was proper. No major oil or air leaks. There were codes that may have been cleared; I used ISTA. The dealer was focused on the camshaft actuation, oil pressure and air plausibility codes. The dealer recommended engine replacement, but I do know many times dealers can be hyperbolic. I did not open the oil filter, but there was a fair amount of vacuum on the oil cap when I opened it while running. It did not stall when I did this. There was oil splashing about as I would hope it would. I did open the expansion tank cap, and the coolant was brownish (and filled to the top), but there did not appear to be oil in it (i dealt with that on an old E30). I did not see white smoke on start up or when revving.

The codes I have are:
2D55 VANOS intake not controllable
2C58 Charging pressure switched off as consequence
2EFE Combustion misfires multiple cylinders
2BEA Fuel air mixture too lean large deviation
2F01 Misfire Cyl 3
2F02 Misfire Cyl 4
2EE2 misfire several cyl; Damaging exhaust gas after starting up
2EEC Misfire Cyl 3;Damaging exhaust gas after starting up
2EF0 Misfire Cyl 4; Damaging exhaust gas after starting up
3429 Engine oil pressure sensor plausibility; pressure too high before engine start

No code for camshaft other than the VANOS related one - quite possibly a solenoid.

I did drive it around the block at about 25 mph, it seemed fine; did not stall or do anything bad, actually.

I have been doing a lot of searching, and i have seen an article describing an HPFP failure mode that disables Cyl 3,4. but I found that rather convenient. And does not explain the oil pressure code.

I want to go back and do a compression test on 3,4 and inspect the oil filter for myself. I've never replaced an engine before, and I know newer cars are fraught with peril about programming this and that (I did replace the head on the aforementioned E30). I do think that if I get it running properly, and get 40,000 miles out of it before the rod bearings completely give out, then it is worth getting.

Any insight is welcomed.

[80stech]

It doesn't work like that. If rod bearings are on the way out it will go very quickly. Do a little research to check if cam journals even have bearings where brass can come from.

[rtwaits]

Thanks, so it goes downhill in a hurry. did read about the problems with the cam ledge, but I think that is aluminum. The Carfax shows 13-15,000 mile oil changes, how special. Interestingly, the oil was changed by some local shop two weeks ago. I believe the cage in the oil filter is still there and not discarded. Still not sure about the metal content of cams.

[ard]

Its like getting diagnosed with incurable stage 4 cancer...and asking about cosmetic surgery.


If you have metal in the oil, dont go chasing after vanos codes. If you dont BELIEVE there was metal in the oil, focus on getting that answered unequivocally. IMO


on re-reading....If you are thinking of buying this and maybe limping aroiund for 40k miles, Id aree w 80stech



While I share in a distrust of dealers, if an oil filter is packed w metal, it needs replacing. Dealers dont rebuild motors- jsut not economically feasible. (Nor do most shops) Of course if you can do a DIY rebuild (tear it down, flush and clean everything, re-assemble) It might not be unfeasible....


my 2 cents

[pshovest]

It's not about oil changes.
The N55 requires a specific oil pump priming procedure if the OFHG or oil cooler are opened, removed or replaced.
In an effort to save fuel, BMW installed a variable volume oil pump in N55's and other engines. This pump reduces the volume of oil pumped to maintain a target pressure. As oil pressure climbs the pump reduced the volume of oil. Previous oil pumps would bypass the excess oil flow to the oil pan. This wastes power & fuel. This pump is fooled by a oil system that is full of air. It reduces pumped volume and oil starvation results.

Rod bearings are the first to go, particularly if the engine is driven hard,

Have an experienced mechanic listen for a rod knock as engine is rev'd in neutral/park.

[Greggo]

I have experienced some similar conditions, with a vehicle that was abused in a past life. Has a new home now, a 'rescue.'

New plugs and a heavy dose of fuel injector cleaner cleared up all the misfire. And a terrible hunting below 1K RPMs, just off idle.

I use SeaFoam, but other products like Techron are a good bet. Used the 'heavy dose,' option. Cleared up almost immediately, like within ten minutes.

After fresh fuel with SeaFoam, very smooth idle, no more hunting. No more misfires on start up.

I think a lot of people overlook the benefit of fuel system cleaners. Once a year maybe. From real experience, solves a lot of strange issues in these high performance engines.

When the engine misfires or hunts, on or just off idle, several systems are affected. Easy cheap place to start.

I put some SeaFoam in a friends 2006 530ix. There were no misfires or strange behavior, but the results were noticeable. He even remarked how well it was running after he picked it up. I did not tell him about the injector cleaner. <lol>