Beiträge von 8er.org

Specific E31 Models Changes

840Ci (1994-95 model)

• 4.0-liter DOHC (4-cam) 32-valve V-8 engine

• 5-speed electronically controlled automatic transmission

• Side directional lights on front fenders

• New steering-wheel design, similar to that in new 7-Series except without audio/cruise/phone controls; diameter increased from 385 to 395 mm (15.2 to 15.6 in.)

• BMW Cellular Phones, CD player and BMW Maintenance optional

850i (1994 model)

• 4-speed electronically controlled automatic transmission only

• Aluminum front brake calipers

• Bird's-eye maple interior trim

850i (1995 model)

• SOHC 5.4 liters V-12 engine, 322 hp

• 5-speed automatic transmission with Steptronic and Adaptive Transmission Control

• Dynamic Stability Control

• Power lumbar support on both front seats

• Automatic recirculation control

• Refined security systems.

850CSi (1994-95 model)

• New model, developed by BMW M (formerly BMW Motorsport)

• Larger V-12 engine: 5.6 liters, 372 hp, 402 lb-ft. torque

• Variable Throttle Linkage

• Variable rpm limiting

• All Season Traction plus 25% limited-slip differential

• Sports-calibrated Servotronic (vehicle-speed-sensitive) power steering

• Lowered and specially calibrated BMW M suspension

• Aluminum front brake calipers

• Wider tires and wheels, different front and rear sizes, unique wheel design

• Specially designed front and rear spoilers

• Four round, polished exhaust outlets

• Premium Yew wood interior trim

• Specially calibrated instruments with red pointers

1994-95 840Ci - 850Ci - 850CSi

All E31 Models

• New ABS 5 antilock braking system (refined ABS operation, integration of All Season Traction system, reduced weight)

• ASC+T system renamed All Season Traction ; standard in all models

• New front spoiler design (different designs for 840/850Ci and 850CSi)

• New Keyless Remote Entry Security System with controls in head of master key

• Driveaway Protection

• For 1994: 10x25-watt (250-watt maximum power) audio system replaces former 4x25-watt (100-watt) system; 12 speakers retained

• For 1995: 10x20-watt audio system

(new rating for 1995 Anti-theft audio system with 12 speakers The 8 Series audio system has equalization custom-tailored to its interior, and 12 speakers.
10 channels of amplification at 20 watts each mean 200 watts of total power.
Please note that this differs from the 250 watts quoted in 1994, which was a maximum power rating.
The new rating is quoted at 10% total harmonic distortion (THD) and is by definition a more conservative figure.
The system has not changed since 1994 models were introduced.)

• Diversity antenna system

Added New Colors for all Models:

• Bright Red (314)

• Orient Blue (317)

• Oxford Green (324)

Added New Colors for 840Ci ONLY:

• Artic Silver (309)

• Cosmos Black (303)

Deleted Colors for All:

• Brilliant Red (308)

• Laguna (Lagoon) Green (266)

• Glacier Blue (280)

• Mauritius Blue (287)

1993 850i

New Designation: from 850i to 850Ci (Coupe Injection)

Standard Equipment:

• Automatic Stability Control Plus Traction (ASC+T was optional)

• Shift lock for automatic transmission - now requires that selector be in Park before ignition key can be removed. Continues to prevent shifting out of Park or Neutral unless engine is running and brake pedal applied
• Passenger's-side airbag; Supplementary Restraint System(dual airbags now standard)

• Newly designed automatic dimming inside rearview mirror (sensitivity adjustment now automatic)

• More deeply gathered leather seating upholstery

• Upgraded materials textures throughout interior and trunk

• Upgraded carpeting

• Bird's-eye maple interior trim

• New center-console design

• Chrome inside door handles and door sills

• Upgraded trunk lining

• Split fold-down rear seats

• Trunk-to-interior pass-through and ski bag

• CFC-free refrigerant in air-conditioning system

• BMW Maintenance Program

1992 850i

• Optional Electronic Damping Control gained a more pronounced differentiation between its Comfort and Sport modes.

• Phonebook scroll feature - cell phone's stored numbers, place a call,or end a call.

• New remote Alarm System

• Seat heating controls moved from seat to console

• Auto-ventilation option available

Just release tension from the belt tensioner, like so:

Once the tensioner relaxes, you should be able to snake the belt off and replace it. Manual indicates you'll need to remove the fan and clutch, but I've been able to do it without this step. Once you've replaced the belt, simply retension by turning the backet against the stop using an open-ended wrench on the top nut and simultaneously retorquing retaining nut with a socket.

One of the easier DIY jobs.

Mark

Slow weekend forces me to bloviate about matters trivial.

Lots of folks have described the dreaded "uneven seat rising" problem, which really is nothing more than a seat drive cable shortening over time inside it's plastic guide sheath. Here are some pictures that might help in seeing where the components are located, and some shortcuts/accumulated learning to ease access to these parts.

If you're going to remove your seatback (not necessary, but loads of fun), the arrows in the picture below indicate the catch points of the headrest trim "elbow". First, run the seat full "down" and start by inserting an ice-pick into the very small hole indicated by the black arrows will release these catches. The catch denoted by the red arrow does not have a hole. You carefully spread the trim pieces apart and insert a flat-bladed screwdriver and firmly press. Pieces should split and release the rear shell.

Here's a shot of what's under the seat, looking forward on the driver's side. Don't worry about mixing up the connectors - they are color- and shape-keyed (thanks, BMW). Notice that LONG seat rail pin - you've gotta lift the heavy seat up sufficiently to free these pins (there are two on either rail) from their locating holes in the body. Tough gymnastic maneuver. Each seat is approximately 70 lbs.

Below is the height adjustment components. This view is directly under the front of the seat, looking rearward. The motor drives two cables emerging from both ends, and retained by a series of lock-plates held in place by two hex screws. The drive cable, contained inside the plastic guide sheath, is a wound piano-wire affair, and shortens over time, retracting the cable from it's drive socket inside both motor ends.

Also, here's where the seat/mirror memory module for both seats and outside mirrors resides (under driver's seat only). Lot of electrical terminations here. I always check and reseat the connectors when I have access to this area.

Below is another shot from one end of the height adjusting motor. It's hard to see here, but there is an inner and outer retaining plate holding each cable into the drive sockets on each end. Removing the hex screws will release both plates and allow you to extract the cable. Also, note the crimp fitting.

Here's a picture of the retaining plates released and the cable removed. Once removed, you can prise off the crimp connector, extract the drive wire, and remove a short section of the plastic guide sheath with a Dremel cutting tool. Reinsert the drive cable, reattach the crimp fitting and re-crimp, and reinsert the cable assembly into the motor and secure. Net savings: About $400 USD. Sorry, don't have any shots of the drive cable or pictures cutting the sheath back.

Those drive cables run back to two gearboxes mounted at the pivot point of the seatback, which in turn drive one of the most complicated scissor-jack setups I've seen in a long time. The quality of metalwork back here is amazing. Here's a picture of the gearboxes looking from the left rear forward on the driver's seat. There are identical pairs on the other side. Note the seatbelt takeup reel and the two relays for the lumbar support and seat heating. Lot going on back there!

Finally, when you recline the seatback, a mechanical linkage raises the headrest. Here you'll see a clever feature: As the headrest lowers and seatback reclines, the seatbelt tension increases through this compensating cable driven by the recliner motor. It winds a stiffening spring inside the seatbelt takeup reel to ensure a constant belt tension. Cool, huh?

So, there you have it. For those of you already familiar with this, my apologies for boring you. For you newbies, I hope you get a better insight into the incredible engineering and quality that went into building the E31. While nothing is simple in these cars, they are remarkably well thought-out and constructed.

Any questions, sound off.

Mark

Here's the belt tensioner in question from the parts list:

Item 7 is probably what's causing the screech - a word tensioner pulley bearing. I'd recommend replacing both this and the tensioner piston, item 15, at the same time.

Removal is simple. Jack the front of the car and remove the lower splash shield (4 bolts). The tensioner is to the left and slightly above/alongside the alternator. Release the tension by unscrewing the larger of the two bolts on the top bracket of the tensioner. Here's a pic:

Once released, you can remove these two nuts and a single bolt below and the entire assembly will come free. Replacement is the same, but you need to retension the belt by placing an open end on the larger of the two top nuts and turning to the left. At the same time, tighten the lower lock nut. Here's another picture:

The same procedure applies for the A/C belt tensioner on the other side, except the pulley assembly is upside down with respect to the alternator version.

Mark

Recently somebody asked about their failing lumbar pump setup. Well, I've had these pictures lying around and just got around to scanning them this weekend. Here's the mystery "bag" tucked into a niche formed between the seat frame and the upholstery trim on my driver's seat. You're looking forward at the backrest from this perspective:

The bag contains the lumbar air pump, and as in typical over-the-top E31 fashion, consists of a handstitched upholstery material, complete with foam backing, tightly enclosing the pump for noise suppression purposes:

Here's what's inside. Pump supplies air, solenoid valve fires to deflate the lumbar cushion, and the switch prevents overpressuring the lumbar cushion and accidental blowouts. R&R consists of checking all the electrical connections and securing the hose connection to the outlet nipple of the pump body.

Pretty simple, but cool, nonetheless.

Mark

First of all, the dealer didn't know what he was talking about. Not unusual. The E31 doesn't have the self-leveling rear suspension. Here's a diagram of the hydraulic system:

The accumulator is "5" in the above diagram, and while the diagram shows it attached to the pressure regulator, due to tight spacing it's actually located forward of the left wheel and attaches to the system via a long series of pipes. Here's a picture of the accumulator, or "bomb" with the left light assembly removed:

So, the procedure is to first turn off the engine after the car is warmed up. Depress brake pedal fully 10-15 times, or until it becomes firm at the top of it's stroke. At this point, you've expended all the stored energy in the accumulator, and the fluid reservoir should now contain the fluid that was stored in the accumulator. Another way to check if the accumulator is depressurized is to remove the cap from the reservoir and depress the brake pedal. If the fluid does not rise, the accumulator is depressurized.

Remove reservoir cover and add Pentosin CHF 7.1 until fluid level is 10mm (about 3/8") from top lip (dimension "A" below"):

With the engine running, the fluid level should drop slight to about 25mm, or about 1" below the lip.

Mark

First, I don't have EDC on my particular car, so this is all theory.

Here's a schematic of the EDC system:

The accelerometers are 2, 4, and 7 in the above diagram. IIRC, the front one (2) is mounted on the underside of the right wheel well (behind the well liner) and senses front lateral acceleration, (4) is the rear lateral acceleration sensor and is mounted in the right rear of the trunk next to the EGS controller, and (7) front/back acceleration and is mounted in the forward part of the jack storage fitting the left trunk. If your mechanic is correct (I'm always skeptical of electrical diagnoses), then replacement shouldn't be too tough for somebody with decent mechanical skills.

I'd also double-check the connectors on the EDC controller in the trunk on the right side.

I doubt the sensors can be repaired.

I'd stop by your dealer's parts counter and determine the price of an sensor over the counter and determine if it's cost effective to replace.

Mark

My 840 was in the stealers at the weekend to find the cause of the Electronic Damper Control malfunction. The light on the centre console comes on at start up but no longer illuminates whilst i'm driving and therefore doesn't allow me to change the ride comfort manually and the car is pemanantly in sport mode.

The dealers reported that the shock absorbers are fine(phew!!) and the problem is the acceleration/speed sensor. They quoted me £300 for the replacement sensor! Has anyone else replaced this part? Can it be repaired rather than replaced? Please help.

Baggio

Yes, you got it right!

I've removed the manifolds so there is no return...
I was hoping that I didn't have to remove the waterpump. I thought it might be possible to remove the rear water manifold instead (it seems impossible to reach its bolts, very tight).

Thanks for the tip about the "cylinder block water jacket cover gasket" I'll follow your recomendations (of course) and replace it to.

Your pics are anything but boring!!! It's so very nice of you to take the time to post them with your instructions/advice. Pics always makes it easier to understand and prevents a lot of missunderstanding.

Thanks again.

/Björn

Bjorn,

I' assuming you mean the long water return pipe running the length of the engine "V" back to the water pump?

For those of you not familiar with what what I'm guessing Bjorn is fixing, here's some background pictures:

Water is returned to the pump via these two pipes. The smaller one returns water from the interior heater core. The larger pipe on the right returns the hot water from the rear of both cylinder heads via a manifold. The pipe leaks here:

So, to fix the leak, the repair manual states:

1.Remove left and right intake manifolds (ouch!)

2.Remove water pump (ouch!)

3.Pull larger of two pipes forward from rear water manifold

4.Replace O-ring in rear water manifold

5.Lubricate O-ring with Vaseline/glycerine/Gummiphlege

6.Reinsert larger of two pipes with twisting motion

7.Reinstall water pump with new pipe O-rings (there are two) at back of water pump

8.Reinstall intake manifolds

I'm assuming you've removed the intake manifolds already and just need to replace the leaking O-ring at the back of the "V" where the larger coolant pipe meets with the rear water manifold. Otherwise, you're facing a lot of work. You might be able replace the O-ring without removing the intake manifolds if you have small hands.

Also, Bjorn, now would be a good time to replace the cylinder block water jacket cover gasket located beneath these two pipes. There's an improved gasket to eliminate the leaks you'll see there.

Sorry if I'm boring you with the pictures. Just figured some folks would like to see the inner workings of the cooling system.

Mark

Thank you Mark for your specific answer I'm impressed!

I tried to find out the funktion myself but with poor result (I have nearly all the electrical schematics on paper but I couldn't make out the funktion...)
Of course you are right when it comes to if my AC works, it don't.
I was informed about that from the seller but not why it didn't work.
It has been converted to the new coolant but the system leaks (it looses preassure over night). I just removed the compressor for having it rebuilt.
As you understand it was VERY interesting to find out about this controlbox before I tried to start the AC again.
Up here in the north we only need it for about max 40 days a year but it is the principle that everything should work that is my goal.

Perhaps you can aswear another question:
What is the best way to remowe the main coolant pipe between the cylinderheads (for changing the O-rings).

Thanks again

/Björn

My guess is....

The Lock Sensor Control Module (A26) senses the following:

A/C compressor RPM via integrated Hall-effect sensor

Engine crankshaft RPM via TD signal from DME cyls 1-6

Engine coolant temperature via NTC sensor

If the engine RPM is greater than 500 RPM, and the A/C compressor RPM is less than 30% of engine RPM, it's assumed the A/C compressor is seized, and this module releases the A/C clutch by interrupting the clutch control signal from the IHKA. Cycling the ignition switch to OFF will reset the module.

It also monitors engine temperature, and if it exceeds 240F (117C), cycles the A/C compressor intermittently for 20 seconds on/off to reduce engine load. It shuts the A/C compressor off complete if engine temperature exceeds 250F (120C).

If this module is disconnected, the A/C compressor should not engage. Does your A/C compressor work?

Mark

When I was trying to fix my servotronic in my 850 -91 I found another riddle!
First of all I just want to say that I consider my car to be very little tampered with. But in my hunt for the servotronic failure I discovered proof that somebody had been there before me, in this case behind the kickpanel (speaker cover) and behind and under the speaker at the driversfeet (you have to remove the speaker to get to it).

When I finally located the plastic bracket that is supposed to hold the servotronic controlbox I discovered two things:

First: The servotronic box is missing and the contacts is just hanging loose (two yellow round ones). For now I'll just connect them together, that will give max power assist independent of speed (I've tried this in my 735-91 and it works! :-).

Second: On the same bracket there are another controlbox, It was disconnected!!! It's labeled LOCK-SENSOR and is aprox. big as an cigarette pack. You can find it in the ETK diagram 61_0809. My box has part no: 6135 139 2 410. In the ETK it can also have no: 6135 836 0 039 it's called CONTROL UNIT LOCK SENSOR.
What does it control??? Except for my servotronic everything works or does it!!!???

As you understand I'm very interested in getting an explanation....

Please help I can't sleep good any more...

I'm very grateful for any theories.

/Björn

Thanks, Mark - I stand corrected. It really seems rare that they both would fail so close together in time. I know they are 'fuel cooled' so maybe the tank isn't being kept full enough to keep them happy.

Derek

The TIS shows the fuel pickup unit partially disassembled with one of the pumps shown moved off to the side. It's understandable how you'd see there only being one pump. The trick to correctly reading E31 parts in the ETK is "quantity", which shows two. Sometimes, like you, I think there's only one fitting, screw, or doodad, and then look over to the quantity column and spy "2".

As to the failure mode - beats me. Perhaps additives attack the various pump parts if the car sits. Maybe it's dissolved water in the gasoline. I thinkt the moral of the story is when something goes south, and there are two, you might as well plan on replacing both. This goes for DK motors, batteries, fuel pumps, regulators, mufflers, O2 sensors, etc.

Mark

Same part number for both. They both are located in the right tank half on a common carrier. There are also two level senders, one in each tank half. Here's a diagram:

1.Swing arm sender

2.Gasket

3.Feed pipe 1

4.Feed pipe 2

5.Fuel pump 1

6.Fuel pump 2

7.Pump holder with rubber liner

8.Fuel filter screen

9.Tank flange

Mark

I replaced one of two fuelpumps a couple of months ago on my 93 850ci auto. Today I am replacing the second one which went out on me this weekend. The car went into 6 cylinder mode each time. Is it normal for the pumps to go out after eight years? Is it a milage thing. The car has 46K on it. Anyway there are only two and now they will both be new. Can I expect any better performance now tha they are both fresh? Thanks for the tips...

Bob

As far as I know we only have one fuel pump on our cars. There is a right and left sunction unit and a right and left sender (for the fuel gauge) but (AFAIK) only one pump. The pump is part # 16 14 1 179 710 and it is on the passenger side of the car under the back seat. The suction units are 16 14 1 180 469 (right) and 16 14 1 180 487 (left). I'm surprised that the pump would go at your low mileage, but I guess it's possible. If they replaced the pump last time then maybe you have a problem with the left pickup (suction unit) and if that's the case it is much less expensive than the pump itself. It might be worthwhile to check the part number of the item they replaced and ask them for the number of the item they suggest replacing now.

Derek

Even though the manifold spacers look fine, they're riddled with tiny hairline cracks, which are sufficient to let air into the intake when the engine is cold. Also, you'll notice the seal bead cast into the surface of new spacers is missing from used spacers, i.e.:

In the high-contrast picture above (sorry), you can barely see the raised bead of the new gaskets around the inside perimeter, which get flattened with time and heat. I also added a thin coating of Hylomar, a non-drying sealant made by Permatext, on both surfaces of the spacers.

I would also strongly encourage you to remove the camshaft covers and check in banjo bolts, particularly the rears. Mine, and several other owners bolts were loose upon examination. Relatively cheap, BMW issued an updated bolt with blue Loctite applied to ensure they'll not loosen. Here's a picture of the bolt and the spraybar it secures. Make sure you clean the spraybar internally and ensure the spray holes are not blocked. Also, purchase new aluminum crush washers for the banjo bolts.

Stephen Cohen had problems with his cork water gasket cover leaking and replaced his, and mine was weeping as well (I deferred since I'll have the engine apart again this summer). And of course, I'd replace all the water, fuel, and vacuum hoses as well, since access to these components is so easy with the top of the engine removed.

Mark