N62 4.8is- Engine REBUILD after Valvetronic/Vanos issues/codes - Page 4

Homerlovesbeer · #1 09-27-2023, 05:22 PM

Well engine back together and at cold start I am having misfire issues. It seems the oil pressure is leaking out of the BMW VANOS Camshaft Sprockets and takes time to build up pressure.

Once the engine is warm and oil pressure restored to the camshaft sprockets the VANOS timing is working as it should be and confirmed through engine diagnostics.

I asked the workshop what needs to be done to fix this and they said new BMW VANOS Camshaft Sprockets.

I've now ordered 2 new BMW VANOS Camshaft Sprockets (intake and exhaust). Genuine BMW units are flapping expensive, FCPeuro has them for US $619 each (here in Australia over $2000 for both).

Screw that.

So I found an OEM manufacturer called Aisin in Japan (25% owned by Toyota) who make them and found them online at https://spareto.com/

Wow SUPER impressed by Spareto.com!

Parts in stock, good prices (I paid only Aus $615 for the parts) and shipping
EXTREMELY fast and great prices. Shipping was Aus $58 to have the parts expressed shipped via DHL to Australia.

I also ordered a new set of wiper blades and purchased Valeo Compact Wiper Blade Set C6055 which cost Aus $32.60 while here is Aus these are Aus $62.25

IMPRESSIVE!

So from ordering online to having the parts at home took only 5 days.

I suggest trying Spareto.com for parts in the future.

So I can drive my car currently and it operates properly once warm, I just need to allow oil pressure to build up so the timing can work properly.

Back into the shop soon for the new VANOS Camshaft Sprockets.

Homerlovesbeer · #2 10-24-2023, 07:23 PM

So a quick update........

I drove over 1000km after the rebuild and had the engine start to misfire occasionally. It would lose power and then come good again.

The next day I took my other half to work a total 2.5km and had the engine lose complete power so I pulled over to the side of the road. I attempted restarts and the engine fired and died again.

The car was towed to the workshop where they said I had a misfire on cylinders 6 and 8 and needed to change the plugs and new coils to determine the issue (although they said they swapped coils and the problem carried over). They also thought it could be bad fuel so drained some out of the tank and it didn't quite look right to them.

So now they've finally changed both Actuator, eccentric shaft (variable valve lift) exhaust and inlet and it still wouldn't run.

The workshop is now claiming EVERY spark plug is bad (even the 2 new ones purchased) and have changed all 8 of them for new ones even though the old ones were only about 1800km old (I put brand new ones in). I am calling BS on this as there is no way 10 bad spark plugs (Denso Iridium TT Twin Tip Spark Plug IK20TT).

So then it fired and wouldn't run.

So now they say bad fuel (was a full tank so over $200 worth) and want to drain it. They also are now saying that the fuel may have damaged the injectors so might need 8 new ones.

What the hell? Really?

I'm beginning to think they have no idea what's wrong and are just throwing parts at it in hope.

What should I do?

X5only · #3 10-24-2023, 08:04 PM

Oh man, sorry for your predicament after spending all that $. What does a diagnostic scan show now?

Nolimite39 · #4 10-24-2023, 08:02 PM

Sounds like you definitely need to find a new shop. Iridium spark plugs really only go bad if they are physically damaged or burnt out, and burning out in 1800kms is not likely.

Homerlovesbeer · #5 10-24-2023, 08:08 PM

They can't get it to run long enough to do a scan.....

The shop has been great so far but this just doesn't seem right......

Edit: Is it possible that bad fuel can damage injectors also? I think that's also a load of BS personally.

Nolimite39 · #6 10-24-2023, 09:19 PM

Bad fuel can potentially clog injectors but you would have had to get some really nasty garbage in there. It's possible with the condition of some of the road houses in the middle of nowhere but if the car has spent its entire life in population centers then the probability decreases greatly. I had a project car sit for like 4 years with fuel in the tank, I started it and was able to drive it without much drama to the gas station. Bad fuel really shows its bad when you're asking a lot of it. At low revs or idling it should be able to maintain well enough. Honestly sounds more like a bad Cam/Crank position sensor, failing vanos (which isn't a normal occurrence in the N62), or possibly the MAF. You can easily test if it's the MAF, unplug it and try to start it. If the problem goes away or greatly decrease strength it's the MAF. I just had mine fail (on an M62) and it was fine until one day it wasn't. Drove the X to work all week, got home on Friday and parked it. Went to move it I to the driveway for some unrelated work on Saturday morning and it wouldn't stay running, hunt idle, etc. Pulled the MAF and the rear cover on the sensing unit had come unglued (sealant bead cracked due to age). New MAF in and all problems are gone. Also any sensor circuit malfunction would appear immediately when you put power to it. Not all codes throw a CEL, have to read them with a decent scanner or INPA.

Homerlovesbeer · #7 10-24-2023, 09:29 PM

Thanks Nolimite39.

I just got a call from the shop. They took the fuel tank out, drained all the fuel, new fuel, cleaned injectors and found some very fine metal shavings in them indicating possible pump wear. Considering whether a new fuel pump is required.

All running fine now and all Vanos codes gone so I may have finally had a win!

They are going to drive it a couple of days before I can have it back.

I'll prob swap out the spark plugs they put in though......

Nolimite39 · #8 10-25-2023, 08:18 AM

That just doesn't sound right. If the fuel pump failed they should have been able to tell immediately by reading fuel pressure which should be a part of normal diagnostic procedure. Also if it failed previously how is it back to good order now? The metal shavings shouldn't be making it through the fuel filter so they couldn't have clogged the injectors. Sounds to me like something wasn't connected or was plugged in incorrectly and they "fixed it" during reassembly. I'd still be asking questions. I don't know anything about your shop and they may be great, I am just very skeptical, especially because so many bmw "mechanics" rely solely on what the car's computer tells them without ever actually performing normal diagnostic. Either way, I hope that's the end of your troubles and you get to enjoy your X.

Just thought about something else. I belive the N62 has dual vanos, if so are they easy to swap connectors on? That will wreak all sorts of havoc. Similar to accidentally swapping the left vanos and vent solenoid connector on an M62.

X5only · #9 10-25-2023, 03:12 PM

Quote:

Originally Posted by Nolimite39

That just doesn't sound right. If the fuel pump failed they should have been able to tell immediately by reading fuel pressure which should be a part of normal diagnostic procedure. Also if it failed previously how is it back to good order now? The metal shavings shouldn't be making it through the fuel filter so they couldn't have clogged the injectors. Sounds to me like something wasn't connected or was plugged in incorrectly and they "fixed it" during reassembly. I'd still be asking questions. I don't know anything about your shop and they may be great, I am just very skeptical, especially because so many bmw "mechanics" rely solely on what the car's computer tells them without ever actually performing normal diagnostic. Either way, I hope that's the end of your troubles and you get to enjoy your X.

Just thought about something else. I belive the N62 has dual vanos, if so are they easy to swap connectors on? That will wreak all sorts of havoc. Similar to accidentally swapping the left vanos and vent solenoid connector on an M62.

Yes, it does. Swapping them and also the cam sensors would cause all manner of havoc - unexplainable misfires, poor idling, etc. Happened to me after doing the valve stem seals.

Homerlovesbeer · #10 10-25-2023, 05:09 PM

Quote:

Originally Posted by Nolimite39

That just doesn't sound right. If the fuel pump failed they should have been able to tell immediately by reading fuel pressure which should be a part of normal diagnostic procedure. Also if it failed previously how is it back to good order now? The metal shavings shouldn't be making it through the fuel filter so they couldn't have clogged the injectors. Sounds to me like something wasn't connected or was plugged in incorrectly and they "fixed it" during reassembly. .

I actually think they were saying that the fuel pump may be about to fail, it didn't stop working and suddenly start working again.

Good point on the shavings making it past the fuel filter, I'll raise that with them.

The shop is a BMW specialist shop full of ex BMW mechanics.

Honestly I think they've done a great job so far, this current issue was a curly one and appears to be bad fuel.

I have no issues recommending the shop.