E34 Firing on all 5 cylinders today!!!

[bimmerman]

Hey Guys,Was driving along in traffic jam today and the weather was especially hot but my trusty E34 never did sweat it one bit. Temperature guage was dead centre. Then suddenly I lost one cylinder and the engine began to shudder. But still had to drive quite a bit in the jam before I could bring her home.Later in the evening I checked all my spark plugs and they were all a healthy brown. Sanded them a little with fine grain sandpaper and put them back but still same problem. Also I notice a sweet smelling gas in the air when the engine was running. Can't tell if it's unspent petrol though. So what could it be guys? Lost a coil? Clogged an injector? Fuel filter dirty? My engine is a M50TU.HELP!!! CNY around the corner and no car to use!

 

[e34kelvin]

Have experienced that before. It was due to a coil.

 

[bimmerman]

Anybody know how to test and see which coil is dead? How much is one of those coils anyway?

 

[ALBundy]

Someone posted a way to test the coil (I think it was KKO from penang). Another way is to find out which cylinder is misfiring, then swap the coils. If after swapping coils, problem is gone then its the coil, if still persists (unlikely), then you are farked :lol: :lol:

Brand new is expensive more than 300 I think :unsure:

 

[bimmerman]

Originally posted by ALBundy@Feb 5 2005, 09:22 AM
Someone posted a way to test the coil (I think it was KKO from penang). Another way is to find out which cylinder is misfiring, then swap the coils. If after swapping coils, problem is gone then its the coil, if still persists (unlikely), then you are farked :lol:  :lol:

Brand new is expensive more than 300 I think :unsure:

Bro, how to test which cylinder is misfiring ah? Is it safe to pull out the ignition cables one by one on a M50TU? Will this fry my electronics? RM300 a piece!!! :blink: pengsan already..... I think i get kedai potong already can lah. Any kedai potong recomendations anyone?

 

[ALBundy]

Switch off your engine first la, before you swap the coils. Do you plan to DIY?? OR have you tried doing DIY in the past? If not, then send to a workshop. If you have, then PM me for instructions.

Rgds

 

[bimmerman]

Originally posted by ALBundy@Feb 5 2005, 09:46 AM
Switch off your engine first la, before you swap the coils. Do you plan to DIY?? OR have you tried doing DIY in the past? If not, then send to a workshop. If you have, then PM me for instructions.

Rgds

I've taken some pictures of the suspect parts bro. Tell me what you think of the following. Really appreciate your help!

 

[bimmerman]

This is what a bad coil is supposed to look like...

 

[bimmerman]

And like this.....

 

[bimmerman]

Mine looks like this.....

 

[bimmerman]

and like this.....

 

[bimmerman]

And these are my plugs.....

What do you think? Plug No.2 looks a little wet because kena some oil when I removed the plugs but should have burnt off if cylinder 2 was firing right?

 

[ALBundy]

For the coils, you cant tell whether they are working or not just by looking at them. I have had similar experience before, a perfectly looking coil but it was faulty! maybe you should swap the coil from cylinder no2 first. How there is oil? Is the valve cover gasket leaking? I am referring to the gasket that protects oil from going into the spark plug (rubber gasket with three holes, 2 pieces for 6 cylinders). If there is a bad leak, will also cause it to misfire.

Now since you have removed it, swap the coils and start the car. The procedure is to remove the coil when the engine is running, one by one. IF the coil is working, when you pull it the socket (the one that connects to the coil) it should misfire! When you repeat the process and it doesnt misfire then that should be the faulty coil!

*disclaimer*
If your car is screwed I am not liable :lol: :lol:

 

[pussy]

looks to me that cylinder no.2 is farked.. could be that a head gasket failure and there's no compresion, hence no combustion..
since you stuck during a hot jam..

or maybe it's just my two cents..

regards

ps.. i got a few spare coils..

 

[bimmerman]

Originally posted by ALBundy@Feb 5 2005, 12:48 PM
For the coils, you cant tell whether they are working or not just by looking at them. I have had similar experience before, a perfectly looking coil but it was faulty! maybe you should swap the coil from cylinder no2 first. How there is oil? Is the valve cover gasket leaking? I am referring to the gasket that protects oil from going into the spark plug (rubber gasket with three holes, 2 pieces for 6 cylinders). If there is a bad leak, will also cause it to misfire.

Now since you have removed it, swap the coils and start the car. The procedure is to remove the coil when the engine is running, one by one. IF the coil is working, when you pull it the socket (the one that connects to the coil) it should misfire! When you repeat the process and it doesnt misfire then that should be the faulty coil!

*disclaimer*
If your car is screwed I am not liable :lol: :lol:

Well I think some oil spilled into the spark plug area during my last oil service so should not be a big worry. Plugs 1 and 2 had some oil at the thread area and spilled into the electrode end of the spark plugs when I removed the spark plug. Thanks for the tip bro! I'll try the procedure and I won't hold you liable for good advise.

 

[bimmerman]

Originally posted by pussy@Feb 5 2005, 02:11 PM
looks to me that cylinder no.2 is farked.. could be that a head gasket failure and there's no compresion, hence no combustion..
since you stuck during a hot jam..

or maybe it's just my two cents..

regards

ps.. i got a few spare coils..

Aiyoh Poos! Now i'm really scared man! I surely hope cylinder 2 is not farqued! It really could not happen at a worse time!!! Poos could I buy one of them spare coils off you? Is it the same spec as mine? Do let me know if can collect from you on monday before I balik kampung. Otherwise got to go borrow a Cantchill alrerady.

p/s: hot traffic jam can also kill coils right?

 

[bimmerman]

OK Bros, found the fault. A BAD COIL. I pulled out each coil connector and plugged it back and each one I pulled had an effect on the engine except coil No.2. I also transferred coil No.2 to another cylinder and it was also dead. So can confirm that coil No.2 is dead right?

 

[bimmerman]

Hey Bros, what's your take on this thingy:

What is it? Why is it cracking? Will it screw up my ride?

 

[bimmerman]

Here's where it is.....

And why does my engine look like it's rotting?

 

[fabianyee]

Originally posted by bimmerman@Feb 6 2005, 12:42 PM
Here's where it is.....

And why does my engine look like it's rotting?

The paint not sticking onto the oxidise aluminum... That's why... nothing much your can do though.... I supposed that's why BMW put black plastic cover for the M5x engines.... M20, M30 and M4x engines are not painted in the first place so it's not that obvious...