CYLINDER CONFIGURATION

I

isambard

New member
Hi all, does anyone know what the cylinder configuration is for my 2003 3.0 SE? I need to know as my engine management light keeps coming on and the guy who diagnosed it says its saying its got a misfire on cylinder 1. He reckons the coil pack may be breaking down, but I have STATICALLY checked them all and they range from 5.55M Ohm to 6.10M Ohm. Which is a reasonable tolerance I suppose? I say statically checked as I realise the readings may differ once under load-hence the 'breaking down', and not broken/failed.

Of course it may just be a dodgy spark plug, and so rather than spend out for a whole new set, change them only to find that it makes no difference, then have to go down the route of a new coil pack, I'd just like to buy one spark plug for cylinder 1, fit it, drive, then wait for the engine management light to come on-or not! :driving:

Any help or further advice will be much appreciated. :)
 
isambard, welcome to the forum... :driving:
I have moved this to the "Problems" area as you are more likely to get a reply to your problem there.... :thumbsup:
 
Coils are a known problem and if one is breaking down, do yourself a favor and change them all. :driving:
 
Adam D said:
How much are the coils each? Was it only early cars that were affected?
Click to expand...

Not sure. My 325Ci that underwent a recall for those coils was a 2003 model. Not sure how many engines (2.5,3.0) were affected nor which years. iirc, they were Bosch coils. There have been a few threads on this, some of which have more info.
 
I dont know if this is what you meant but ill write it anyway! :)

Cylinder numbers ususally count upwards from the cam belt/chain towards the flywheel. So on ours it'd be:

Front of car - Camchain - Cylinder1 - 2 - 3 - 4 - 5 - 6 - Flywheel - Back of car
 
Before you buy stuff, here's a trick you can try to diagnose it.

Remove Coil #1 and swap it with Coil #2. If the code moves to Cylinder #2 it's the coil, if not swap coils back where originally and swap plug #1 with plug #2. If code moves, you have a bad plug. If the code still on Cylinder #1 you have a problem somewhere else (eg wiring, or injector)...

I wouldn't change them all, there's no reason to replace what's working... It's not like you need to take half car apart if in the future another coil fails...
 
Thanks for all your input guys. Ed, yes it is the info I was looking for, thanks. Where did you get it from? Is it 100%, or are you summising?

ZetaTre: yes I could do that but it would mean me driving the car back and forth to the indy that does my diagnosing, as I have no equipment myself. And we've got about 1ft of snow here at the moment-even my X5 is struggling!! My front end had a fight with a lamppost today... :headbang: Yes snow in the UK-we usually just get rain-haha! And I too believe its not worth changing them all, as I dont want to fix what isn't broken, not too mention the waste of cash. I mean suppose it is just a loose wire or further (not-so obvious) issues...? Thanks for your advice all the same Smokin.

Adam: They are as low as £13.50 + vat which is a pattern part from eurocarparts, though I would much prefer to pay the £15 odd + vat each for a Bosch.

So, with the info Ed has supplied I'll get one coil and one plug tomorrow and change them both, as a precaution. If it works I will have saved myself nearly £100. If it doesn't I'll be out of pocket £25, and trying out ZetaTre's (but my idea too!! :wink: ) idea and play musical coils'n'plugs!!
 
Cant you rent diagnostic tools in the UK... Here in the US I just go at any auto-parts store, and get a tool. All they ask is a 100% refundable deposit: basically you give a $100, get the tool, use it (I think you can keep it for a couple of days or so), then return it, and get your $100 back. Any OBD2 reader reads miss-fire codes and reset the CEL...
 
99% of all inline engines are that way mate. :thumbsup: V's however work differently, but i wont go into that! :lol:

They basically do that on a longditudinal engine because the flywheel will always be pointing toward the rear wheels. Therefore its simplest to designate "Cylinder1" as the one at the front end of the car!

I dunno if you're aware of this but make sure that when you're swapping over coils, you know which HT lead went where! Mixing them up can cause major problems! Also beware that Spark Plugs in Alu cylinder heads should be treated VERY carefully. Blow out the plug canal to remove any crap and make sure you dont tighten a cold plug into a hot head... Just passing on advice ive learnt the hard way in the distant past! :thumbsup:
 
Excellent advice above, you don't wanna strip the threads!

Recommend a 12" extension bar and a magnetic spark plug socket (the rubber ones are not so clever) and 'feel' the threads in by fingers and wind down using fingers until you need to torque, half past snug using the ratchet (1/2 - 3/4 of a turn once the crush washer gives resistance to turning).

Thanks for the rough price, cheaper than I expected - I occassionally get a small stutter or surge in the rpm band @4k. This was fixed once before by flashing the dme but it has returned, wonder if it would be a iffy coil pack breaking down.
 
Check out this tread. It shows the coils and how to replace them....

http://www.z4-forum.com/forum/viewtopic.php?f=12&t=1937

The early models were build with NON-Bosch coils. The recall/TSB had them replaced with Bosch coils....
 
Shipkiller said:
The early models were build with NON-Bosch coils. The recall/TSB had them replaced with Bosch coils....
Click to expand...

Thanks for clearing that up! I had them in the wrong sequence. :oops:
 
Thanks all for your replies fellas.

ZetaTre: Dont know about the renting of diagnostic tools-to be honest I've never thought of it! Will look into it and find out more! Sounds a bargain if its the same over here!!

Ed: Thanks for your advice, though I've been an Engineer for 20 years and have been playing around with all my cars for that long also-so the stuff about being careful with stripping threads and stuff not needed. Not having a pop at all mate, just saying. Thank you for the info anyway. :) Just needed to confirm where Cyl 1 was. Again, thank you. :thumbsup: Also, I dont know if you're aware or had a look, but there are no HT leads, just thin wires with a connector plug on the end that the coilpack plugs in to. These are cut to length for each individual spark plug position, so you'd do well to get them mixed up!!

Anyhoo, I have changed the single coilpack at cyl 1 pos'n (didnt change sparkplug as I would not be able to determine EXACTLY what the cause was by mixing and matching, and would have meant me making TWO trips to my Indy), got my man to reset the ECU, and now its all good. Total cost: £18 for coilpack (Eurocarparts) + 10 mins changing coilpack + £20 for resetting ECU, as well as 30 mins round trip travelling to my indy. Not bad me thinks for a tip-top motor again!! :driving:

Thank you to you all for your contributions. :D
 
Does anybody know of a way to reset the ECU without plugging it into a diagnostic machine? On my old car it would forget the stored settings and relearn after ~ 5 minute disconnected from the battery.
 
If you are talking about the Engine Management learned baseline settings stored in the ECU, then disconnecting the battery does the trick.. If you are talking about clearing any error codes you may have popped then it depends.. Some of the low level diagnostic codes will clear when you disconnect the battery. Higher level/more severe problems will stay... Also, any SRS Airbag codes are NOT reset when power is lost, but they are not stored in the ECU.
 
You must log in or register to reply here.
Back
Top Bottom