[eljay]

In good news department, I replaced the accessory belt, tensioner and idler pulley. The udler pulley was the culprit behind the noise. The belt looked very good, but it's a good piece of mind to have everything refreshed.
The engine bay is now nice and quiet - like it should be - until those DISAs open up.

It was a pretty quick process:
- remove the two T20 screws holding the air duct from the grille area to the air filter housing and remove the duct.
- note the belt routing
- insert T60 bit on a breaker bar into the slot on the tensioner and turn clockwose to relieve the tension and slide off the belt from the pulley.
- remove the belt
- remove E14 bolt from the tensioner assembly and discard the bolt. Do not reuse it.
- remove tensioner assembly and clean the area and pay attention that dirt does not end up in the grooves on the main crank pulley.
- install new tensioner assembly with new aluminum bolt. The torque is 25Nm (18 ft-lbs) + 90 degrees.
- remove plastic cap from the center of the idler pulley
- remove 16mm hex bolt from the idler pulley
- install new idler pulley with new bolt. Torque: 40Nm.
- Install new belt making sure you guide it onto all the grooves of the pulleys. Slide it onto the tensioner pulley last.
- with pliers in one hand gripping the securing pin and breaker bar with T60 in the tensioner slot, relieve tension a bit so you can slide the securing pin out if the tensioner assembly and release the tension.
- check the belt
- start the car and check that the belt runs properly without touching anything on its sides
- reinstall the air duct
- have a beer

[4 Doors]

Originally Posted by eljay

In good news department, I replaced the accessory belt, tensioner and idler pulley. The udler pulley was the culprit behind the noise. The belt looked very good, but it's a good piece of mind to have everything refreshed.
The engine bay is now nice and quiet - like it should be - until those DISAs open up.

It was a pretty quick process:
- remove the two T20 screws holding the air duct from the grille area to the air filter housing and remove the duct.
- note the belt routing
- insert T60 bit on a breaker bar into the slot on the tensioner and turn clockwose to relieve the tension and slide off the belt from the pulley.
- remove the belt
- remove E14 bolt from the tensioner assembly and discard the bolt. Do not reuse it.
- remove tensioner assembly and clean the area and pay attention that dirt does not end up in the grooves on the main crank pulley.
- install new tensioner assembly with new aluminum bolt. The torque is 25Nm (18 ft-lbs) + 90 degrees.
- remove plastic cap from the center of the idler pulley
- remove 16mm hex bolt from the idler pulley
- install new idler pulley with new bolt. Torque: 40Nm.
- Install new belt making sure you guide it onto all the grooves of the pulleys. Slide it onto the tensioner pulley last.
- with pliers in one hand gripping the securing pin and breaker bar with T60 in the tensioner slot, relieve tension a bit so you can slide the securing pin out if the tensioner assembly and release the tension.
- check the belt
- start the car and check that the belt runs properly without touching anything on its sides
- reinstall the air duct
- have a beer

I just finished this process last night, as well as an OFHG. It really is a simple procedure and nice peace of mind. Good work!

[eljay]

Originally Posted by eljay

I got an error message about brake pad wear indicator and found out that my rear brake pad wear sensor is just hanging and no longer attached to the pad. It must've come loose as I didn't guide it through the rubber holder that is part of the bleeder screw cap. Don't skip this step when you bleed your brakes boys and girls!
I'm happy that I saved the good sensor that came with my 335i calipers, so I took the wheel off and removed a part of the wheel liner and unclipped the old sensor wire and installed the "new" one and the error went away.

BUT, in the process of getting behind the liner, I discovered that one of the connectors leading to the battery box is badly corroded and the housing is cracked. I've since read that they are both 12V leads with one going to the starter/alternator and the other powering the DME and electronics. I need to read uo to find which is which. So, the next question is how to fix this before it leaves me stranded somewhere.
Can just that part be replaced? I hope it's not part of a looong battery cable that leads to the engine compartment that needs to be replaced as a whole.

Would this have anything to do with my SOS malfunction error? I guess I should really check the fuse box now to see if all is well there.

Oh and while I had the car lifted, I noticed that the bump stop on the rear driver's side shock is split in half and the top of the shock shaft has corrosion on it. I hope it lasts the winter as I will be installing ST coilovers in the spring.

It seems that I'm on a roll with fix one, find one.

For some reason, my attachment did not show up, but I since found another thread with similar issue from the past and my connector looks very similar: cracked and corroded:


It's part of a battery lead cable, which is like $500 from BMW. They apparently also sell a repair kit for "only" $210+tax. Lovely.
So, I guess I'll need to hunt down a used good connector and find a way to crimp it on properly. Any tips on how to crimp a battery cable? Replacing the whole thing would be a huge pain as it goes from the rear to the engine bay, alternator and starter. And I just replaced the starter....
I wonder if that's what slowly killed the starter and if I don't address this, the new one won't last too long either.

[nsjames]

what I would do is a bulkhead connector and two battery cable ends.

the cheap whack it with a hammer battery cable crimper works. but will be difficult to use in situ.

you can buy the cheap HF hydraulic cutters and grind the cutter into a crimper with a dremel.

obviously you should cover all the connectors with adhesive lined heatshrink, and you're gonna have to cap each side of the bulkhead connector. It won't be as flush as the BMW solution, but it will only cost about $5 in parts to fix.

[eljay]

Originally Posted by nsjames

what I would do is a bulkhead connector and two battery cable ends.

the cheap whack it with a hammer battery cable crimper works. but will be difficult to use in situ.

you can buy the cheap HF hydraulic cutters and grind the cutter into a crimper with a dremel.

obviously you should cover all the connectors with adhesive lined heatshrink, and you're gonna have to cap each side of the bulkhead connector. It won't be as flush as the BMW solution, but it will only cost about $5 in parts to fix.

Having a hard time finding that bulkhead connector locally. I'll call NAPA tomorrow, but their website does not list it.

[eljay]

Back to the MOST troubleshooting...
I followed this video:

and determined that I have light at the connector leading into the amplifier, but the connector to the TCU shows no light. Just to confirm, TCU is the next in the MOST loop, correct?

I verified that the amp harness has 12V when the radio is on and the fuse for the amp is good. I didn't take it out to check whether a yellow light on it is blinking like in the video. I'll do that tomorrow.

Does this point to a dead amp?

[eljay]

Not having a good time with the E91 lately!!
This morning, I started it up and got a low coolant message. So, off it goes into garage until I get some coolant from the dealer and then figure out if it's just a seasonal cold-temp coolant low event that a little top-up can solve, or something else. I noticed a bit of a wet spot on the bottom of the engine bay cover (the aluminum one) and a spot in the driveway. I thought the spot on the splash shield was from previous owners' oil changes and the leaking VCG. But the oil level is rock steady since my oil change, so it may be coolant. I couldn't tell the colour as it was covered in dirt. And while I looked under the car upon startup, I also noticed an exhaust leak, which appears to be from the downpipe to mid-pipe connection, so that gasket is likely gone.

Sooo, in the past two months: zero refrigerant in A/C, starter, VCG, idler pulley, rear brake pad sensor, rear battery transfer point, dead amp (likely), coolant low, exhaust leak, stuck rear wiper. Lovely!!!!
What will fail next?!

[4 Doors]

How many miles on your E91 at this point? Honestly those are not devastating repairs. Most are common maintenance repairs/items that fail over time. Unfortunately they seem to have happened close together for you. I feel for you and honestly understand it is a pain when the repairs have to be done.

But in the long run, you complete them and they will reward you with reliability.

Optimistically, this gives you an excuse to put headers or an exhaust system on

[eljay]

Originally Posted by 4 Doors

How many miles on your E91 at this point? Honestly those are not devastating repairs. Most are common maintenance repairs/items that fail over time. Unfortunately they seem to have happened close together for you. I feel for you and honestly understand it is a pain when the repairs have to be done.

But in the long run, you complete them and they will reward you with reliability.

Optimistically, this gives you an excuse to put headers or an exhaust system on

89K miles / 143k kms.

Yeah, I wouldn't mind those things, but not when winter starts and we need two cars and I discover one thing after next. It's tough being an enthusiast because you actually notice things going wrong on your cars.
I have friends who wouldn't have noticed any of this until the car would stop and then they casually mention that "yeah, there was that 'stop driving' message on screen, but I thought it was just a suggestion because it's been there for weeks and I could still drive."

[nsjames]

on the other hand I've got 165k miles and have experienced none of those issues. sometimes you just get unlucky.

[Tambohamilton]

Originally Posted by eljay

It's tough being an enthusiast because you actually notice things going wrong on your cars.

+1. My partner rolls her eyes at me for noticing noises and things on our cars. She never noticed the timing chain noises on her N47...BMW dealer said the equivalent of "wait and see", but I was paranoid that they'd worsen rapidly and unpredictably, so did them anyhow...There was the slightest wear on the plastic rails, and maybe one chain had stretched a little...maybe. Oh well!

[eljay]

When I look at my car history, I typically spend my car ownership cycle (around 5 years) getting it perfect for the next owner. :

[Tambohamilton]

You should sell to a family member or friend, so at least you can enjoy the benefits vicariously

[eljay]

Originally Posted by Tambohamilton

You should sell to a family member or friend, so at least you can enjoy the benefits vicariously

True.
Or keep it for the next 100k, so I enjoy at least some fruits of my labour.

I looked under the car today and didn't see any coolant leaks anywhere.
I haven't done anything with the cooling system and don't know if the previous owner did. So, I'll get some coolant from the dealer in the morning and top it up and monitor.
I do see that the oil pan gasket seems to be weeping. Nothing on the belly pan, but oil oan is coated. I'm not losing any oil, so I'll just leave it for now.

I took a closer look at the exhaust and the downpipe to midpipe flange is very crusty, so no wonder there's a leak. It's certainly not just a gasket job, but new flanges woukd need to be welded on, I think.

Did anyone deal with this? Can a shop just cut off both flanges and join the two sections with clamp sleeves instead?
And no, I don't want to go catless.

[rothwem]

Originally Posted by eljay

So, off it goes into garage until I get some coolant from the dealer

I guess a lot of people don't have distilled water sitting around there house (maybe it's just because I've got a young child?) but it's usually not the worst thing in the world to top your cooking system up with some distilled water if it's a pinch low and you don't have any coolant handy.

[Buug959]

Originally Posted by rothwem

I guess a lot of people don't have distilled water sitting around there house (maybe it's just because I've got a young child?) but it's usually not the worst thing in the world to top your cooking system up with some distilled water if it's a pinch low and you don't have any coolant handy.

The only problem with that is that it raises the freezing point of the coolant. It's risky here in Nova Scotia because the temperature can change drastically overnight and you could end up with a damaged cooling system from the coolant freezing. It's better to top up with the correct mix of coolant.

[krhodes1]

Originally Posted by LemansE90335xi

The only problem with that is that it raises the freezing point of the coolant. It's risky here in Nova Scotia because the temperature can change drastically overnight and you could end up with a damaged cooling system from the coolant freezing. It's better to top up with the correct mix of coolant.

The amount that a liter of distilled water is going to change the mix is almost certainly irrelevant, assuming you were somewhere around 50:50 to start with, and don't live at the North Pole. You only need about 30% coolant to have the freezing point well below zero.

See chart here: https://www.sparkplugs.com/quest-for...-coolant-ratio

[eljay]

Yes, if I was in a pinch far from home, I'd just add distilled water, which I have at home, but since we have a second car, I just went to the dealer to get coolant and topped up with 50/50 mix. CAD$48. Wow. They are really pushing it. Audi coolant is $20.

As an aside, I saw the new 4-series "grille" in the showroom and I must say that despite the hate (which I had toaards it as well), it actually works pretty well on a dark grey 440i they had there.

Any suggestions for the exhaust joint solution? I guess I'll just take it to an exhaust shop and have them come up with something to solve that and get that PE muffler installed too.

[Tambohamilton]

I don't like sleeve joints, and would be surprised if that flanges couldn't be cleaned up then sealed by a new gasket... But YMMV, of course. I'd get some replacement bolts and take the joint apart to see what you're up against, then make a call from there.

[eljay]

Originally Posted by Tambohamilton

I don't like sleeve joints, and would be surprised if that flanges couldn't be cleaned up then sealed by a new gasket... But YMMV, of course. I'd get some replacement bolts and take the joint apart to see what you're up against, then make a call from there.

I don't like them either as that joint should be more flexible, but I don't know how I can save this:



I think they will have weld new flanges on. Hopefully, they can do that on the car on the downpipe portion as I'm not about to pay for removing the exhaust manifold.

[Tambohamilton]

Touché. That is way more crusty than I anticipated. I think it's still worth an investigative disassembly, but yeah...that's not pretty.

[krhodes1]

Originally Posted by eljay

I don't like them either as that joint should be more flexible, but I don't know how I can save this:

I think they will have weld new flanges on. Hopefully, they can do that on the car on the downpipe portion as I'm not about to pay for removing the exhaust manifold.

Wow - that is impressively awful. Shame you are on the wrong side of the Gulf of Maine (do you guys call it the Gulf of Nova Scotia? ), I have the exhaust from my '11 e91 that was taken off at less than 3K miles that I would just give you to get it out of my garage.

If you will be in Maine post-pandemic, it is yours for the taking.