Replacing HT Leads & Spark plugs

[tentonhammer 10]

Ok So I've said in a previous post that my C 92' 16V 2.0 (9A) is intermittently misfiring - Which is still happening from time to time (f*cking weird). Think the misfiring could be down to carbon build up on the spark plugs / bad HT leads etc ( i bet they've never been changed) so I'd like to replace the whole lot to be sure. Most high end HT leads have a 10 year life span, considering the car's 20 years old it's a sure bet.

 

I've already got a new set of Bosch plugs plus a 14mm spark plug socket so good to go here.

 

What I do need though is a new set of HT leads - Preferably with the cylinder 4 end of cycle sensor / pick up sensor I think it's called, already installed (9A engines only)

 

Looking at Magnecor 7.0 - 8.5mm - See below

 

http://www.demon-tweeks.co.uk/performance/ignition-leads/car/volkswagen/corrado/1996/2-0-16v/magnecor-7mm-performance-ignition-leads-black

 

Managed to find these slightly cheaper at £155.00 delivered at DC Performance

 

http://www.dcperformance.co.uk/cheap/617880/volkswagen/magnecor-7mm-ignition-leads/mgn-47516.html

 

Anyone got any other recommendations?

Edited August 9, 2012 by tentonhammer

[Jim 2]

Do a search for this information mate - I went through it extensively when I went through the same process and documented where I got my leads from. You need to get a set which actually allow you to unscrew the plugs at the distributor end to put on the reference sensor, and the vast majority out there which are "compatible with 2.0 16v (9A)" are anything but!

 

---------- Post added at 10:02 AM ---------- Previous post was at 10:00 AM ----------

 

I believe it's these ones:

 

http://www.ebay.co.uk/itm/CORRADO-GOLF-PASSAT-1-8-2-0-16V-86-IGNITION-LEADS-111-/230829314293?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item35be7fd0f5#ht_535wt_844

 

The seller does another, cheaper set which are not compatible (OEF 520).. but these should be (OEF 111)!

[tentonhammer 10]

Thanks Jim,

 

Presume the end of cycle reference sensor isn't part of the HT lead then - Hence why it needs to be re-attached to cylinder 4 HT lead?

[Jim 2]

Indeed - it's not part of the lead. The end of the lead will unscrew allowing you to remove it but I'll warn you now - it's a complete f@cker to get off and on. The plastic loop on the sensor seems just too small to get over the metal bits crimped onto the lead (you'll see when you unscrew them) - I ended up having to spend a lot of time trying to reshape it, warming up and greasing the plastic sensor to make it easier to slide on, etc etc none of which worked.

 

I think what I ultimately ended up doing was unpicking the metal crimp, putting the sensor over the lead, and then reassembling the crimp.

 

New sensors are still available from VW - they cost in the region of £60 if you fancy changing it at the same time.

 

:)

[tentonhammer 10]

Sounds like a right pain in the arse I'll look forward to that one cheers, but then I hadn't expected it to be straight forward (if only!).

 

Just tried to fit new Bosch spark plugs on my lunch break and my 20mm spark plug socket (that fits spark plug) was too big to fit through the holes in the cylinder head cam cover! I reckon I've been sold the wrong fecking plugs :C The box says 10mm plug but just measured the damn thread on the thing and it looks like 12mm - wrong plug in the right box, no wonder the socket's too big!! I'll never buy from Halfords ever again...

 

Wouldn't happen to know correct thread size for 16V 2.0 spark plug?

[Purplebaghera 0]

I got these came with knock sensor and new guide already to fit! http://www.candrenterprises.co.uk/shop/blue-igniter-high-performance-ignition-leads-vw-1989-1995.html

[Jim 2]

Sounds like a right pain in the arse I'll look forward to that one cheers, but then I hadn't expected it to be straight forward (if only!).

 

Just tried to fit new Bosch spark plugs on my lunch break and my 20mm spark plug socket (that fits spark plug) was too big to fit through the holes in the cylinder head cam cover! I reckon I've been sold the wrong fecking plugs :C The box says 10mm plug but just measured the damn thread on the thing and it looks like 12mm - wrong plug in the right box, no wonder the socket's too big!! I'll never buy from Halfords ever again...

 

Wouldn't happen to know correct thread size for 16V 2.0 spark plug?

 

Googling around it sounds like it needs to be 16mm!

 

Regarding the other leads mentioned by Purplebagheera - they sound worth a punt if they have the knock sensor already included! Handy!

[Stonejag 10]

Just tried to fit new Bosch spark plugs on my lunch break and my 20mm spark plug socket (that fits spark plug) was too big to fit through the holes in the cylinder head cam cover! I reckon I've been sold the wrong fecking plugs :C The box says 10mm plug but just measured the damn thread on the thing and it looks like 12mm - wrong plug in the right box, no wonder the socket's too big!! I'll never buy from Halfords ever again...

Might be obvious but some are sold with a thread adapter on them. If so, if you unscrew the terminal at the top there's a smaller terminal underneath :)

 

I had the same head-scratching moment when buying plugs for the ex's Golf so you wouldn't be the first...

 

Stone

[tentonhammer 10]

Managed to have another butchers at this last night - turns out the thread size on the new plugs were correct (12mm) but the nut (butt end of plug) was too big hence why it couldn't fit through cam cover hole. Halfords not only sold me the wrong plugs but the wrong socket too! No wonder I've been scratching my head over this too.

 

Anyway I'll have to order new plugs to ensure they're correct.

 

Purplebagheera - Thanks these look great, pretty much exactly what I'm after except (but man I wish I wasn't this fussy...) I want them in black. Blue will look odd in the bay.

 

To confirm, HT leads will need to have a pre-fitted guide sensor (AKA pickup or impulse sensor) AND knock sensor (fitted to lead 4) to allow for a straight swap?

[Jim 2]

Not entirely. The lead is designed to be undone so that you can put the sensor on but I think only genuine VW leads are actually designed well enough to allow you to do it. The more expensive of the leads I linked too will work fine but you just may have to be willing to dismantle the lead a little - will take you 10-20 mins tops.

 

To be certain you get the right ones you could just go to VW :)

[tentonhammer 10]

You're probably right Jim, buying directly from VW could be safest bet - Will check costs and lead time.

 

Funny thing about all this is that what should have been a simple plug + HT lead swap has now turned into a MUCH bigger job...

 

I found oil all over plug 1 (body and electrode), plug 4 wasn't great either. Think cam cover gasket might be blown, and possibly valves seals as well :C Any advice on replacing these, tools required etc?

[davidwort 0]

when you say oil all over plug 1, do you mean it's leaked down onto the top of the plug from the centre cam cover seal or the tip inside the combustion chamber is fouled?

Cam cover gasket isn't too bad to do, but you will need an inlet manifold gasket too, as that will break when you remove the inlet unless it is very new.

changing the valve stem seals is a lot more involved and really needs the head taking off as the valve springs and cotters need to be removed, I've heard of it being done with an air line into the combustion chamber or rope fed into the spark plug hole to keep the valves up.

edit, sorry, read your post properly, cam cover gasket is almost certainly leaking, but you could have a headgasket problem too, stem seals don't usually foul plugs badly, you just burn a bit of oil.

[Jim 2]

As David says, the cam cover gasket(s) are easy to replace as is the inlet manifold gasket - an hours work at worst. It could just be those leaking and indeed it's quite common for them to fail with age. There are two gaskets for the rocker cover - the main outer one and then an inner one to seal the spark plug "chambers".

 

A little oil down those chambers goes a LONG way - I spilled a tiny bit when topping up the oil once and it took me ages to get it all out of there. Every time I pulled the plug lead to check there was a bit on there for a long time after.

[tentonhammer 10]

Do you happen to know what type of inlet manifold gasket is used on the 9A - Is it the oval type or the 50mm round type?

 

Found a place that will send them out on Saturday delivery (want to sort this this weekend) so I have to get my order in to them in like 30 minutes!

[Jim 2]

round..

[tentonhammer 10]

Great, because that's what I ordered ;)

 

Replacement rocker cover gasket set and inlet manifold gasket in the post - Will tackle this tomorrow.

 

Any useful guides on how to replace these anywhere? Looks pretty straight forward to replace them but always good to get the heads up on stuff like this

 

Cheers

Edited August 10, 2012 by tentonhammer

[davidwort 0]

they are both round :lol: but I know what you mean, the smaller 42mm inlet on the corrados is round all along the inlet runners wheras the 50mm 'squeezes' past the plugs, both gaskets are actually round though.

 

nothing much to note on doing the job other than make sure vac hoses go back where they should under the inlet elbow and don't overtighten the brackets that support the inlet to the back of the head as the head is softer alloy.

Might as well give the inlet and throttle body a good clean while off, I also removed the internal casting seams from mine as my lower inlet tract had already been ported and polished inside , no need to smooth polish it though it should have an even but slightly rough surface, you could also 'waist' the throttle butterfly pivot and smooth the throttle body too :)

 

[ATTACH=CONFIG]68907[/ATTACH][ATTACH=CONFIG]68908[/ATTACH]

Edited August 10, 2012 by davidwort

[tentonhammer 10]

Fitted NGK Spark plugs (BKUR7ET) and all good.

 

However, I bought OE HT Leads (see spec below) I was told that they could be unscrewed to fit original knock sensor if necessary etc - This unfortunately wasn't the case...

 

http://www.ebay.co.uk/itm/CORRADO-GOLF-PASSAT-1-8-2-0-16V-86-IGNITION-LEADS-111-/230829314293?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item35be7fd0f5#ht_535wt_844&clk_rvr_id=375367674945

 

I removed my old leads and found nothing that even resembled a knock sensor, or sensor of any type that could be screwed on to the dizzy end of plug 4 for that matter??? There was nothing attached to plug 4 at all, inside or outside. It appears I've been running the car without one! Not sure what the implications of doing this are, I gather I shouldn't be running the car without one, perhaps somebody could explain, even a pic of the sensor would be useful(!)

 

I plan to send the leads back anyway and fit leads that already have the knock sensor installed - should have done this in the first place really but I presumed I had a knock sensor already fitted to the car, which it turns out i don't. Made sense to go for OE replacement leads which were £60.00 as opposed to £125.00 with knock sensor installed. Fitting the sensor sounded a piece of p*ss to do too.

 

What a pain in the ars*

 

---------- Post added at 8:36 PM ---------- Previous post was at 8:32 PM ----------

 

BTW replaced cam cover gasket set and manifold gasket no problem, cleaned throttle body too while I was at it - No probs here.

 

Thanks David for the heads up

Edited August 14, 2012 by tentonhammer

[Jim 2]

I am confused. That's the eBay seller I used and after a failed experience buying the cheaper versions of those leads they sent me those ones and I could definitely unscrew the plug at one of the ends (I don't remember which) to fit the sensor. Sorry for the misinformation - it just doesn't match my experience at all! :(

 

This is the email I received after I queried the original leads I received, from a couple of years ago:

 

Hiya there

 

Sorry to hear you are having trouble with the leads we supplied. This lead set is not made to fit a sensor but we have 2 solutions for you.

 

(1) These leads are not designed to have a sensor fitted but we do have a Copper version that can have a sensor fitted. We would happily exchange for these, even though the leads have already been fitted but they would be around £13.00 more expensive. They are on Ebay at £26.00 more but we could do the discount because of the confusion.

 

(2) If you would prefer to keep the current lead set a sensor would be compatible if you could fit it on. If you send us your knock sensor we would be able to have a single lead made with your sensor already on. We would also need to know the exposed cable length of the lead you need it fitting to.

 

Please let us know which option is best for you and we will arrange.

 

Kind regards

 

Edited August 14, 2012 by Jim

[tentonhammer 10]

Hi Jim,

 

No dramas mate, perhaps they're using a different supplier now? I asked the seller before I bought them re knock sensor and they said I would be able to unscrew one end to fit it (if I even had one on my car! see previous post), think they may have sent me the wrong ones that's all. Have asked for a refund anyway, hopefully I'll be able to get my money back with little hassle.

 

I'll need to get a impulse sender as I don't have one - Can somebody clear something up for me:

 

What does the pinned plug attach to? See indication below

 

[ATTACH=CONFIG]69001[/ATTACH]

 

I presume the ECU?

 

ANSWER: Connector from ECU (length of wire from ECU to engine bay)

Edited October 27, 2012 by tentonhammer