e34 pre-purchase checks?

[antony 0]

Hey

My friend is looking at buying an e34 1989 525i auto (m20b25).

Any advice on what to look out for/common faults would be much appreciated.

Thanks

Antony

[kiwi535 538]

e 34 hs a few common faults,mostly relatively eay fix.E34 .net used to have a scary page called what will break but it is being rebuilt..

e 34 issues

90 km hr clunk/shimmy ussualy fixed new control arm and bushing

rear wiring on boot hinge breaks resukting in bogus warnings /electrical /lockig issues

make sure radiator etc is up to it.

[Creaver 55]

90 km hr clunk/shimmy ussualy fixed new control arm and bushing

rear wiring on boot hinge breaks resukting in bogus warnings /electrical /lockig issues

these 2 I had/have on my e34. Paul's on the money.

[OLLIE 26]

interesting the boot wiring problem, i have bogus central locking issues. How do you go about remedying this?

[Creaver 55]

interesting the boot wiring problem, i have bogus central locking issues. How do you go about remedying this?

When the guy installed my alarm, he resoldered loose/frayed wires. Because the boot opened/closed all the time the wires flexed and broke.

[melowpuf 19]

interesting the boot wiring problem, i have bogus central locking issues. How do you go about remedying this?

Whats it doing Ollie?? One issue I have seen lots is doors locking and then unlocking again straight away and unlocking and locking again. Easy fix - lift the back seat and replace the blown fuse under the back seat. Check the loom in the boot to see if any wires are frayed causing a short.

The fraying loom in the boot is another common one.

Light issues (Bulbs are good but headlamps/tail lights still not working) Check/replace the LKM (Light control module)

Cooling hoses - old cooling hoses = bad, wont be long till they crack and start leaking, you lose water and over heat and do a head gasket (lost count of how many times I have seen this). Replace a hose a week if you can't afford to get them all in one go. Its cheaper than a replacement head.

A compression test will tell you what condition the bottom end is in.

Cam belt - self explanatory. If you can do this yourself DO IT again anyway. its cheap enough.

Rust - check at the bottom of the rear windscreen in the corners, the boot lid covers it when closed so open the boot. Water pools in the corners, I have seen a few with rust there.

The Shimmy as already discussed. may also be hub rings if it has aftermarket wheels on it.

Test drive the car before the engine has been warmed up - take it for a drive around the block, the trans can slip when cold sometimes. If it does slip and goes away when it is warmed up you maybe lucky and might get away with a trans flush and new filter.

Loose steering or play in the steering - Idler arm most of the time, easy fix just a nut, tighten it up.

Check the shocks - if it feels like your driving a water bed, they're poked.

They're like e30's. But bigger. and easier to work on.

Edited July 28, 2008 by melowpuf

[kiwi535 538]

interesting the boot wiring problem, i have bogus central locking issues. How do you go about remedying this?

can be shorts in the boot wiring(remember the boot is part of the system in that you can lock/unlock the car from the boot),or the door actuators dont quite open fully and the gm interprets this as a bogus signal so locks(or unlocks) the car again.

EDIT the actuator/GM issue applies to early e34,s...symptom is you unlock car and it immediately locks itself again..or visa versa

The LKM can be resoldered,where the mini relays attach to the circuit board...i will post more as the memory slowly recalls things

Edited July 28, 2008 by kiwi535

[rxsumo 33]

Other stuff not already mentioned....

Plasma display in the dash can go AWOL, its a capacitor problem and there is a website that details the fix.

Heater control valve can fail, this means that the heater runs hot all the time, can be temporarily resolved with a gentle tap.

Check the rear end links, they are ball joints and can wear out once the rubber seals perish.

If the check computer is given BS readings, just reseat the computer located in the LHS rear of the engine bay.

Electric seat controls can get rather flaky over time, I've had switch illumination fail, and the memory function go west, athough the rest of the controls stayed functional

Watch out for over-rated bulbs and dodgy trailer wiring. The E34s are really sensitive in wiring department. 100W bulbs will cause fuses to blow.

[jochen 4]

Plasma display in the dash can go AWOL

Wow, that's an E30 ahead of its time. I'm not sure if plasma displays were invented 20 years ago.

LCD displays, however, were quite common to find in BMWs.....

[antony 0]

Thanks heaps guys, we took it for a drive, and when running it was leaking an uncomfortable amount of oil. So he's not getting the car, but I think the drive sold him on an e34.

[rxsumo 33]

Wow, that's an E30 ahead of its time. I'm not sure if plasma displays were invented 20 years ago.

LCD displays, however, were quite common to find in BMWs.....

I worked on cash registers over 25 years ago, that had plasma displays, ie they werent LED or LCD, my assumption is that the BMW displays are something similar.

They had a liquid filled unit that needed voltage to fire them up so that they would light up. At the time LCD was typically a black display, that required backlighting to be illuminated.