E34 BMW M5

Hi gents, made some progress. Found that the 12v fuel pump cable is broken. Sorted it out and the pump now pumps when attempting to start.

Still has the terrible miss due to C4 plug lead. Need to get a set for testing or at least one long cable to check C4. I'm really hoping that sorts out the miss.
 

UpNcOmiNg!

Events Organiser
Benji said:
Great to see you got it running! Misfiring on these can be any number of issues. The plug leads are M5 specific and are really expensive for a set. Im sure you could make your own with the right tools and patience, but first make sure that the spark lead is the culprit. Do you have the correct spark plugs? They are quite an unusual type and hard to find - Bosch Y6DC. Open up the distributor cap and check for wear. Clean with emery paper or replace - cap is R650 for Bremi at GW, rotor is about R150.

These motors are also notorious for vacuum leaks which can cause any number of issues. Positive pressure smoke test or soapy bubble test is your friend here. I would probably start with the vacuum system.

Failing that, balance the throttle bodies and make sure each cylinder is seeing equal vacuum at idle (when hot)

Great advice! :praise:
 
UpNcOmiNg! said:
Benji said:
Great to see you got it running! Misfiring on these can be any number of issues. The plug leads are M5 specific and are really expensive for a set. Im sure you could make your own with the right tools and patience, but first make sure that the spark lead is the culprit. Do you have the correct spark plugs? They are quite an unusual type and hard to find - Bosch Y6DC. Open up the distributor cap and check for wear. Clean with emery paper or replace - cap is R650 for Bremi at GW, rotor is about R150.

These motors are also notorious for vacuum leaks which can cause any number of issues. Positive pressure smoke test or soapy bubble test is your friend here. I would probably start with the vacuum system.

Failing that, balance the throttle bodies and make sure each cylinder is seeing equal vacuum at idle (when hot)

Great advice! :praise:

Thanks for the sound advice. The car currently has some NGK R plugs in (not sure how good or bad they are).

What I did to test the problem
With all 6 plug leads in, the car misses
With C4 plug removed, it sounds about the same as all 6 connected.
With C4 and another plug removed, the car dies
I then removed C5 and fitted in the position of C4. Car starts much better and upon start up, still sounds like 5 cylinders.

Doesn't seem like any rotor issues at the coil although, I'll still check anyway.
 

Benji

Well-known member
200 octane said:
Thanks for the sound advice. The car currently has some NGK R plugs in (not sure how good or bad they are).

What I did to test the problem
With all 6 plug leads in, the car misses
With C4 plug removed, it sounds about the same as all 6 connected.
With C4 and another plug removed, the car dies
I then removed C5 and fitted in the position of C4. Car starts much better and upon start up, still sounds like 5 cylinders.

Doesn't seem like any rotor issues at the coil although, I'll still check anyway.

It does seem like the ignition lead. Have you tried measuring the resistance/continuity of the leads? I would still encourage to check for vacuum leaks as a starting point. These cars will do strange things when they have vacuum leaks.

It was quite a while ago that I bought spark plugs. I cant remember why, I just know that after all the research I did (and phoning around), I ended up importing 12 Bosch spark plugs from the UK. It worked out to R120 a spark plug while the cheapest I found in SA was R250 each.
 
A big shout out to @"UpNcOmiNg!" and @"Benji"
Car starts from the outside without help. Dizzy cap had some corrosion inside so I'll be replacing cap and rotor soon.

Besides the above, I'll just be tucking away some cables to make space for the driver's seat so that I can do some testing.

Been a while since I had one of those ear to ear smiles.?
 
I tucked the driver's side cables and fitted the driver's seat last night. I'll be testing it around the corner today to check for the fans and to see that engine/cooling temps are constant.

It has an oil leak but also has bucket loads of grime attached to the sump from standing for so long. Hoping that a pressure hose will sort that out later. Other than that, it fired up on the first swing earlier this morning around 8:20.
 
Just completed the love boats maiden voyage (with me)
Put a smile on my face. Still has a slight miss which I suspect now is the corroded dizzy cap. Already stripped for replacement.
 
Hi guys, so I had my first spirited drive in the M5 and what a thrill. The feeling of the car taking off and kind of escaping you....simply amazing. I really didnt expect it to be too fast due to body size but was I mistaken. I've had a T3/T4 Turbo setup Nissan 200sti before that made 230kw at the wheels but that's wasted power if not sent to the rear. I really enjoy the machine sound of BMW and then also the grounded and mechanical feel of the 5 series. I've put off owning a bmw for very long because I always wanted an M car and then when I could afford it, it made no sense buying since I'm a rep.

Alas, here I am today and feeling blessed to own an iconic BMW.

Definitely have alot of maintenance to do
Ball joints
Steering rack play
Oil leak (does the sump have a gasket or use sealer)
Control arm bushes etc
 

Benji

Well-known member
This is awesome to hear bud. I remember falling in love with the M5 the first time I could properly open her up...Front suspension parts are all easy to get from GW (make sure you get the aluminum lower arms) and tighten the suspension up when the car is on the ground. Oil sump needs a gasket...this is also on my list to do, can be done with the engine in, but you need to undo the engine mounts and lift the engine as high as it will go. Maybe be a good idea to replace the chain tensioner while youre in there (use E36 M3 upgraded part)
 
Benji said:
This is awesome to hear bud. I remember falling in love with the M5 the first time I could properly open her up...Front suspension parts are all easy to get from GW (make sure you get the aluminum lower arms) and tighten the suspension up when the car is on the ground. Oil sump needs a gasket...this is also on my list to do, can be done with the engine in, but you need to undo the engine mounts and lift the engine as high as it will go. Maybe be a good idea to replace the chain tensioner while youre in there (use E36 M3 upgraded part)

Thanks Benji, I'll have a look at it when I start stripping and make a list of what's needed.
 

UpNcOmiNg!

Events Organiser
As Benji mentioned, get that tensioner and make that upgrade sooner rather than later.
I have had to rebuild one of these motors due to that tensioner failing! Cheap part, expensive consequences!
 
The car successfully drove to it's new house. Moved on Saturday and removed the loom on Sunday. The loom is all taped up, just need to solder about 6 connections before taping that section up and then ready to refit. Should be able to start the refit tomorrow (wednesday) and then I can tuck it away one time and refit interior. Let's see...

Once this is done, I'll tackle the engine cleanup so that I can identify the leak. My major problem here is that this would have been an easy job at the old house whereas I might piss some people off at the new location.
 
Benji said:
This is awesome to hear bud. I remember falling in love with the M5 the first time I could properly open her up...Front suspension parts are all easy to get from GW (make sure you get the aluminum lower arms) and tighten the suspension up when the car is on the ground. Oil sump needs a gasket...this is also on my list to do, can be done with the engine in, but you need to undo the engine mounts and lift the engine as high as it will go. Maybe be a good idea to replace the chain tensioner while youre in there (use E36 M3 upgraded part)
Hi guys, where can I buy the M3 tensioner as mentioned above and what would I ask for?
 
200 octane said:
Benji said:
This is awesome to hear bud. I remember falling in love with the M5 the first time I could properly open her up...Front suspension parts are all easy to get from GW (make sure you get the aluminum lower arms) and tighten the suspension up when the car is on the ground. Oil sump needs a gasket...this is also on my list to do, can be done with the engine in, but you need to undo the engine mounts and lift the engine as high as it will go. Maybe be a good idea to replace the chain tensioner while youre in there (use E36 M3 upgraded part)
Hi guys, where can I buy the M3 tensioner as mentioned above and what would I ask for?
Probably the dealer
 

Benji

Well-known member
200 octane said:
Benji said:
This is awesome to hear bud. I remember falling in love with the M5 the first time I could properly open her up...Front suspension parts are all easy to get from GW (make sure you get the aluminum lower arms) and tighten the suspension up when the car is on the ground. Oil sump needs a gasket...this is also on my list to do, can be done with the engine in, but you need to undo the engine mounts and lift the engine as high as it will go. Maybe be a good idea to replace the chain tensioner while youre in there (use E36 M3 upgraded part)
Hi guys, where can I buy the M3 tensioner as mentioned above and what would I ask for?

BMW E36 M3 chain tensioner, part number 11311405081. I paid R1944 ex VAT for mine at ABM. You also need the oil seal, part number [font=Calibri, sans-serif]07 11 9 963 418 - R16 ex VAT. [/font]Just make sure when you buy it that the spring is still inside the unit - they sometimes pop out/come apart and then its just headaches. Do a google - there are DIYs out there that show how to do the process. Something about filling the tensioner with thick oil before installing it to make your life easier...I havent done it yet so I couldnt give you more info
 

UpNcOmiNg!

Events Organiser
And while you there you may as well do a cambelt service and waterpump etc, makes life easier seeing as you in the vicinity.
 
Top