Issues with first 300 miles of ownership - The Unofficial BMW M5 Messageboard (m5board.com)

CWY_M5 · 28th June 2008, 21:48

So I acquired a '91 E34 M5 back in Dec of 2007, and really have done quite a bit of work.... and really haven't driven it much at all.. now I have a few issues I would like to solicit help from you guys.

background:
I also own a E39 2000 MY M5, did some work my self
on this E34 M5, it only had 110.6K miles, everything seems original
Things I have revamped so far:
- Entire suspension, front and back, SLS delete, Dinan Spring and Koni adj.
- All control arms and bushings and steering linkages (center, idler, etc)
- new water pump, thermostadt, belts and hoses
- valve adj, valve gasket, new cap rotors and wires (damn expensive wires)
- plugs of course, all fresh fluids, brake, rotors, brand new
- leaky power steering pump, so got a re manufactured installed
- new engine mount, they were shot

Now the issues:
- Runs a bit rough, idles about 950 RPM, a bit high. Using computer on the car, it reads 3.2 L/H on idle - is this normal? My E39 runs at 1.7 L/H at idle
- Car runs VERY HOT - in traffic, I'm very very close to RED... is this normal? system is brand new with new fluid, and the shop says bleeding is done
- Dash lighting is very dim, is there a write up somewhere I can refer to to replace some bulbs?
- AC does not work, and shop can't figure out yet. Pressure seems to hold, any clue where I could check for electrical fuses?

minor and tedious ones:
- interir light keeps tripping fuse 21 (10A), and so far, I've gone thru a box of fuses, don't know what causes this
- Rear speaker connection is funky, one on the right doesn't work right. I know it's not speaker or head unit, because I swapped with my E34 525, and confirmed it must be in the connection or the line somewhere... bad news
- Steering is a bit loose, I will try adjusting that bolt on the steering box sometime
- no remote keyless - gotta be kidding me... hoping there's a way to add one

Other than that, I feel the car lacks torque (spoiled by the E39), but with new suspension, it's rather tight and nimble, not worse than E39 actually. Accelleration seems to kick in after 4K RPM, a very noticeable kick.

Looking forward to helpe from folks here.

CWY

mottati · 28th June 2008, 22:24

idle speed sounds about normal. These engines have a fairly high idle speed. I've not checked the fuel consumption myself, but based on how the car smells at idle, i'd believe it needs a lot of fuel to idle. My car's idle is not smooth, and remembering when these cars were new (i worked at my local bmw dealership in college, circa 1988-1992) they never were smooth at idle. Should smooth out with a little revs though.

Coolant temp is not normal, i'd try bleeding the system again. I've read that these cars are difficult to bleed air from the system, but honestly, when i did my cooling system overhaul over the winter, it seemed pretty straightforward to me. Note that the bleeder screw is at the back of the engine compartment, by the heater valves (maybe your shop didn't bleed from there). Open it up, let the engine idle, and see what happens.

If the temp issue is only in traffic, how is the fan clutch and aux fan?

When you press the ac button, does it light up? Can you hear the clutch engage and aux fan start? I just had my ac recharged (old r134a conversion) and am pleased with how well it works.

Depending on the production date, you may be able to add the factory remote keyless entry. IIRC, the wiring harness should be under the back seat, if your car is pre wired.

You need to drive it more! (once you get the temp issue sorted), i notice my car runs better the more i use it (probably placebo). Took it for a drive with the family to my parents last night, and commented on what a nice highway car it is. Yes, power comes on at 4k rpm, so a bit different from the e39, but very fun, imho. As for nimbleness and tossability, i'd say the e34 is much better than the e39, it's a fun car to drive on a winding road, in the right gear, in the meat of the powerband. We had a great group drive up to 5erfest earlier in the month up thru the sierra's, what fun that was.

DrSakke · 28th June 2008, 23:03

Hi!!
Rough running:
These cars do idle roughly, you should feel the car vibrating a bit on idle. Idle speed should be 750-850rpms , Is the 950 with or without AC? because when AC is on the idle goes up to ca 950rpms.
Idle consumption is not that interesting, does the car use a lot when driving around??? how did the old plugs look like????sooted or discolored???
Possible fault sources: idler valve on the plenum, throttle position sensor or vacuum leaks(check the rubber boot after MAF for cracks.
The power kick you describe suggests that your resonance flap in the plenum is functional.

Running hot: Is that only in urban traffic or all the time, also on the highway???If the temp varies, I would suggest that the viscous fan has packed in. It should be audible when the car runs hot, can you hear it kick in??? also the AC fan in front of the radiator assist in cooling, change the resistor on the fan shroud and check that the fan is functional(direct 12v power source to the leads while changing the resistor) . Otherwise i could be that the radiator has clogged and the flow is poor. aftermarket rad is not too expensive.
Also change the temp sensor for the gauge first so that you exclude the cheapest fault (20$) it sits on the aluminium housing above the viscous fan.

Lighting:
You know that the lighting is adjustable?? (not trying to be a smart *** , just asking) the wheel for that is on the left side of the binnacle.
If you on the other hand see that there are bulbs that have gone (sections of the cluster are dark) then the procedure is to remove the cluster and change ALL the bulbs (so that you avoid doing the same job twice).
The difficulty of this depends on which steering wheel you`ve got, if it is the 3 -spoke, non.airbag wheel, then. the only way is to remove the wheel first. If you`ve got the four spoke bus wheel with airbag, then you can remove the cluster without removing the wheel.
I believe this has been described here before, the search function is very good.

But anyway, here goes:
Remove two screws in the cluster house(on top/leading edge of the instrument cluster, then draw the cluster towards the steering wheel so that you can get your fingers behind the cluster house and detach wiring(quite easy) then draw the cluster in the top hole of the 4-spoke wheel and rotate the wheel anti-clock wise until the cluster comes free.
If the wheel is the smaller three spoke variant then all this is a piece of cake as the wheel is no longer in the way.
Split the cluster (self explanatory when there) and change bulbs) , after this the same procedure in reverse order.DONT TURN ON THE IGNITION WHILE THE WIRING IS DISCONNECTED , this will give you fault codes that you have to reset at a BMW dealer.

I won`t comment on the AC as I don`t know anything about how to troubleshoot it, but it has been discussed here, make a search.

Interiour lighting:
Propably short circuiting either at the light or at the door switch, check wiring(even to the rear hatch as faulty wiring here i usual and can give random symtoms.

Lastly: Upgrade the timing chain tensioner to the E36 M3 3.2(euro) part (96 and onwards) could save you a lot of trouble.

useful links:
http://www.bmwe34m5.com/node/1

http://www.e38.org/e34/

http://www.unofficialbmw.com/frame_e34.html

http://www.bmwe34.net/Wiki/tiki-inde...ge=Maintenance

light bulb in the centre console:
http://www.bmwe34.net/Wiki/tiki-inde...e=Panel+lights

Sakke

camlob · 29th June 2008, 01:19

Yup I agree with Mike on the bleeding. Mine was like yours before and the needle would inch up all the way a little beyond 3/4. After bleeding, my needle never goes beyond 1/2 and thats with 40c weather! BTW I also put overhauled my viscous fan so it could probably help too.

Paul

nebpor · 29th June 2008, 03:33

Temp symptoms exactly the same as mine when my viscous fan went - straightforward to change yourself as well.

Good luck with ownership, it can be a pig ... but it's worth it

woods · 29th June 2008, 06:17

Running hot only in traffic = fan issues. Running hot all the time very likely means air in the system (since it seems everything else is brand new in your case). Hot is the needle anywhere above the half way mark BTW.

The speaker issue is a PITA. There is an amp in the trunk on the left hand side and wiring harnesses that goes to and from it. My car had an intermittent front right speaker and the problem was in the harness coming from the amp right there in the trunk. Pull the panel out of the trunk and try wiggling the speaker harness around a bit... The wires are all colour coded and the info on which is which can be found at bmwe34.net. Note - BMW amps power each speaker individually. If both the mids and tweeters are out in one corner - the problem is likely in the headunit->amp harness. If it's just the mid or tweeter alone - it's in the amp->speaker connection.

Cheers.

CWY_M5 · 30th June 2008, 22:14

Thanks to all for your comments - work in progress it is...

I'll respond to some of your questions - still hoping to see more:

Running HOT, only in traffic, and in idle. When cruising or even driving hard, temp is always in the middle. Does that mean it is NOT a bleeding issue?

I do hear a fan coming on when hot, so it must be the Aux fan. What's the viscous fan mentioned?? is that the fan clutch? or the fan that runs with the engine?

I'll try bleeding in any case if I can find it.

Idle rough - seems this is quite common, and in relatively high RMP as well. Can someone simply confirm the L/H on the computer when idle? 3.2 L/H seems high, as my E34 525 and my E39 M5 both run at 1.4~1.6 range.
(To get this reading, hit 1000 and 10 at the same time, and use the "1" to go to test 3 or 4 I believe. If it's locked, go to test 19 to get ie free)

Interior light, I have tried removing every light bulb except three up front by the sun roof switch, and it still trips. Problem is, I can't find a pattern of when it trips... these cheap fuses are becoming expensive... do they sell a "resettable" one for 10 A?

Lastly, AC, the switch inside does light up, but don't feel the car does anything, no compressor kicking in, no fan kicking in, not even an idle increase.

On the rear speaker / amp, can you elaborate where it is? is it under the carpet on the driver side, or is it just mounted next to where CD Player would be?

Back-light, yeah, one or many of the bulbs are out - I'm still looking for a write up somewhere, can't find it. Where can I get the bulbs before I tear it apart?

DrSakke · 30th June 2008, 23:55

Quote:

Originally Posted by CWY_M5

Thanks to all for your comments - work in progress it is...

I'll respond to some of your questions - still hoping to see more:

Running HOT, only in traffic, and in idle. When cruising or even driving hard, temp is always in the middle. Does that mean it is NOT a bleeding issue?

I do hear a fan coming on when hot, so it must be the Aux fan. What's the viscous fan mentioned?? is that the fan clutch? or the fan that runs with the engine?

I'll try bleeding in any case if I can find it.

Idle rough - seems this is quite common, and in relatively high RMP as well. Can someone simply confirm the L/H on the computer when idle? 3.2 L/H seems high, as my E34 525 and my E39 M5 both run at 1.4~1.6 range.
(To get this reading, hit 1000 and 10 at the same time, and use the "1" to go to test 3 or 4 I believe. If it's locked, go to test 19 to get ie free)

Interior light, I have tried removing every light bulb except three up front by the sun roof switch, and it still trips. Problem is, I can't find a pattern of when it trips... these cheap fuses are becoming expensive... do they sell a "resettable" one for 10 A?

Lastly, AC, the switch inside does light up, but don't feel the car does anything, no compressor kicking in, no fan kicking in, not even an idle increase.

On the rear speaker / amp, can you elaborate where it is? is it under the carpet on the driver side, or is it just mounted next to where CD Player would be?

Back-light, yeah, one or many of the bulbs are out - I'm still looking for a write up somewhere, can't find it. Where can I get the bulbs before I tear it apart?

Hi!
If running hot only in traffic, I would suggest it indeed is a issue either with the fan clutch/viscous fan (meaning the fan running with the engine-it is coupled to the engine thorugh a viscous clutch that is temperature regulated) or aux fan(in front of the radiator.
When you hear the fan coming on, please confrm which one it is. while the engine is running, take a swift tour to the front of the car and look for the aux fan running through the lower bumper holes. then switch of the engine and test the viscous clutch through trying to rotate it manually. It should be stiff if is working.
Just make sure you don`t let the engine overheat while doing this.
Bleeding the system one more time doesn`t do any harm either.

If the radiator is the original one, it could well be clogged if everything else works.

Reg. the interiour light fuse...
Chech the cables to the trunk lid, could be that(I dont remember if the fuse is the same for trunk lighting, but i would think so)

AC.....

In one or two of the links (e34.net) I provided, there is a troubleshooting "manual" for the AC. Other than that I cant help. propably shot compressor if the system holds the correct pressure. The aux fan should start when the AC is activated, but if the system is non-functional it may not start other than as an over heating protection-see part one.
On the other side, the AC should work even if the aux fan is shot(mine did for 4 years before I repared the fan, often a resistor failure) And the fan is quite quiet, so you have to go and have a look see......

The dash lights.....
I just gave you a write up

It really is not rocket science. Which wheel do you have????
There is only to screws holding the cluster, you can see those easily if you look up towards the "roof" of the hole from behind the wheel. Other than that you only have to unplugg the wiring (connectors with lever locks-wery easy). The only problem is the steering wheel( if you have to remove it or not.)
The bulbs are standard items and can be found anywhere they sell autoparts. the warning lights are 2W with plastic socket(if I remeber correctly) and the main lighting is 3 or 5W (I cant remember if they were the type with glass base or the push-and -rotate metal socket, buy both as there is only 3-4 of them.(I`m sorry it is propably 5 years ago I did this so the bulbs have gone from my memory) Just make sure to change them all while you`re at it.

taa
Sakke

DrSakke · 1st July 2008, 00:13

Write ups on the instrument cluster removal provided in the links in my first post....
http://www.bmwe34m5.com/node/214

http://www.bmwe34m5.com/node/66

Sakke

CWY_M5 · 1st July 2008, 02:58

Dr Sakke - AWESOME... Thanks.. I got lots to do this weekend... :-) Will report back