A slightly poorly VR-4

[elnevio]

Time for a story, kiddies! Hope you are sitting comfortably...


Once upon a time, there was a Trigger Mauve VR-4, that was running lovely.

One day, it developed a slight stutter. The stutter went away briefly. Then suddenly reappeared as a smacking great loud misfire!

You could hear the misfire in the engine bay, and it sounded like it was coming from the top of the engine at the front. Given the very bad idle and the sound from the engine, it was as if one of the spark plugs had been removed, and the plug well left open for the compressed mixture to escape through an alternative route..


The long and the short of it, today was my first opportunity to get the engine cover off and see if anything stood out.

So, of came the Y-pipe and engine cover, and I was presented with this view:

01 - Initial view.jpg

As can be seen, there was 'wetness' in the general region of the spark plug wells, and also to the side of the oil filler cap. This wetness smelled a bit 'fuelly'.

A closer look around the middle coil pack revealed some odd bits, looking distinctly like they shouldn't be there:

02 - Something odd.jpg 03 - Something else odd.jpg

Further investigation, and removal, revealed this collection of items:

04 - Not as much as there should be!.jpg

That is a coil pack and a spark plug that are not in the same shape that I last left them in!

Here is the insulator end of the plug:

05 - Missing top.jpg

The lead connector appears to be absent!

Oh, there it is!

06 - Oh, there it is!.jpg

And what's that?!

07 - Not ssure about this bit!.jpg

I assume it's a bit from the coil pack, although it looks about the same shape and size as a watch strap pin.

Here's part of the coil pack connector core:

08 - Coil pack core.jpg

And here is the business end of the spark plug:

09 - Missing electrode!.jpg

Oh, it is suspiciously absent! I wonder where that went...

10 - Coil pack - not what it once was.jpg

All four or five inches of the plug connector part of the coil pack has excused itself!

As you can see, there are some bits of it in the pictures, most of which had blown out of the plug well and while some had remained near the coil packs, the rest appears to have been ejected!



So there you have it. Something has occurred that has involved the spark plug being spat out of its home, and it seems that quite a few combustion cycles have taken place that have battered the two components to bits! You can see all the indentations on and around the spark plug hex fitting from its obviously very rough ride.

Now, I don't know what bits have made their way through the exhaust system (if any, but I doubt that nothing at all went through) taking bits of turbo with them, etc., so the obvious step was to change the plugs and fit my spare coil pack, seeing how well it runs after that.


Anyway, upon fitting the spark plug to the affected cylinder (which is number 4 - the front middle, by the way), it wouldn't bite and screw in.

Further investigation revealed another problem. Either the initial action of the spark plug deseating itself, or the plug continuously travelling in and out of the threaded hole, has basically made the hole bigger:

11 - Oversized spark plug well.jpg 12 - Normal spark plug well.jpg

I used a magnetic retrieval tool to indicate the difference in size. The right picture is a normal hole, and the left picture is the affected hole. In both pictures, the round end of the tool is touching one side of the hole. As you can see, the hole is probably about 2mm greater in diameter now! The inside of the hole is pretty much smooth, with little trace of a thread remaining...



So, I now have to consider my options... oh, no I don't - a plan is afoot, and it involves the Leggie being back on the road this month, leaving the May trip to the Ring unjeopardised!

Watch this space...

[Nutter_John]

That really is mullered , was there any bits in the chamber when you shoved your magnetic tool down there

[horndog]

So, I now have to consider my options... oh, no I don't - a plan is afoot, and it involves the Leggie being back on the road this month

Let me guess, your transferring the Power from the Swift into the leggy,

[foxdie]

This is quite shocking actually, glad you've got plans to sort it but holy crap, that's one hell of a mess Nev

[Nick Mann]

Bummer, Nev. Hope the plan is a good one and that it works!

Not knowing what the plan is, I'd suggest that you ought to expect the possibility of:
Damage to valve seats/valves.
Damage to piston crown.
Damage to cylinder head (extra to what you have highlighted above!)
Unseated rockers.

I look forward to seeing it back on the road soon!

[Ryan]

How on earth did that happen I wonder? Sorry Nev... that's not good news. Does that mean new engine time?

[MarkSanne]

OUCH!!! Never seen that before on a 6A13TT! Good luck getting it proper and back to work again.

[The Vee]

Not good at all. If it's not whole engine replacement you're looking at, then check the turbo on that bank of cylinders, if anything did go that way, it won't have liked it. Sorry to see this bud.

[Chris.W]

Holly sweat mother of all things automotive, how in the hell did you manage that???

Looks prety screwed up son, maby cross threaded the plug on fitting perhaps?

Has the look of a mild case of terminal damage to either the turbo, piston or crown chamber of the affected cylinder.

Engine upgrade on the cards??

[psbarham]

**** dude you was lucky.

the only time I've seen anything like that was when a plug hadn't been tightened properly. fixed it with a helicoil kit.

[Mark 4]

Yup, could be as simple as a helicoil. Good luck with it Nev.

[elnevio]

That really is mullered , was there any bits in the chamber when you shoved your magnetic tool down there

The piston appeared to be at TDC, but I couldn't see anything. I didn't shove my tool all the way in though!

Let me guess, your transferring the Power from the Swift into the leggy,

Funnily enough, this is something I laughingly mused over when selling the V6, with a view to putting the old V6 engine in the back of the Swift!

**** dude you was lucky.

the only time I've seen anything like that was when a plug hadn't been tightened properly. fixed it with a helicoil kit.

Yup, could be as simple as a helicoil. Good luck with it Nev.

The helicoil would be a consideration, but it has its drawbacks for me. I cover this some more below!

Bummer, Nev. Hope the plan is a good one and that it works!

Not knowing what the plan is, I'd suggest that you ought to expect the possibility of:
Damage to valve seats/valves.
Damage to piston crown.
Damage to cylinder head (extra to what you have highlighted above!)
Unseated rockers.

I look forward to seeing it back on the road soon!

How on earth did that happen I wonder? Sorry Nev... that's not good news. Does that mean new engine time?

Not good at all. If it's not whole engine replacement you're looking at, then check the turbo on that bank of cylinders, if anything did go that way, it won't have liked it. Sorry to see this bud.

Holly sweat mother of all things automotive, how in the hell did you manage that???

Looks prety screwed up son, maby cross threaded the plug on fitting perhaps?

Has the look of a mild case of terminal damage to either the turbo, piston or crown chamber of the affected cylinder.

Engine upgrade on the cards??

The plugs (Denso Iridium IK22s) have been in for about 25,000 miles - and inspected in that time. I'd like to think that cross-threaded is highly unlikely, given that they have always been straight-forward to remove and replace, never being seized, and except for the initial untightening/final tightening, screwed in easily and freely by hand.

There is the possibility of lean running being the culprit - perhaps a detonation event occurred that took the end of the plug off, and then combustion would have been occurring inside the plug core? It will mostly be a guessing game, that is certain. Even if repaired, the chance of it occurring again might not be low enough for me.

So a half-inch piece of hard iridium spark plug core broke off and probably bounced around the combustion chamber for a number of cycles, doing whatever damage, before disappearing out of an exhaust port and through the turbo. At least there isn't a cat on the vehicle to get trashed!

Then there is consideration to whatever other unknown bits got blown through...

Essentially, the condition of the engine and front turbo is unknown. There may be damage to the head, valves, piston and/or turbo - some of which may not actually prevent the car from running, but it could be running at a weakened level or even just be a ticking time-bomb with a significantly-shortened life span. I know nothing is 100% certain, but I'd rather not have something like this eating away at the peace of mind.

Then there is the convenience factor to consider - how long to have the car off the road for, fitting the work in, doing some work, then finding out it isn't doing the job and having to sort it out again. The work involved here, whilst possibly not beyond my capabilities, is almost certainly beyond my current knowledge, definitely outside of my comfort zone and miles beyond the time I have available.


What you have probably guessed is that this is heading to is a full engine swap.

I have a known engine (well, still running in a car right now!) lined up for transplant, which has similar miles to mine (70-80,000).

No fault-finding, no attempted fixes - just straight to the convenient, one-stop solution!

This involves the minimum of fuss and inconvenience, and will be sorted in one-go.


The cost of this will be somewhat mitigated by the cost of upcoming jobs (be it parts, my time, or someone else's time) that I would have been paying out for on my existing engine anyway - some of which will be much easier on an engine which is out of the car. This includes fresh and cleaned injectors, spark plugs, cambelt, water pump, TC seal. All fresh fluids - coolant, engine oil, ATF. Cambelt and water pump job on its own is a few hundred quid's worth, so takes a substantial chunk out of the cost of engine replacement.


And it'll all be in time for it's next MoT!

[mike74]

A couple of thousand miles after i first got my Pulsar it started running like a sack of poop. When I pulled the plugs for a look, one of the ceramic insulator nose's had sheared and was sitting around the electrode. They were Denso's too & I binned the whole lot of them, never to be used again. I've heard other similar stories about faulty Denso plugs too!
I hope its just the plug thats failed & hasn't caused any other major damage (well, apart from the head)!

[Mark 4]

Sounds like a plan Nev. Good luck with it.

[foxdie]

There is the possibility of lean running being the culprit - perhaps a detonation event occurred that took the end of the plug off, and then combustion would have been occurring inside the plug core?

I suddenly feel the need to check all my plugs

[Davezj]

sorry to hear of your problems nev.

i think you have the right idea swaping the whole engine, if you can get one cheaply enough. it is your long term best solution if you are not happy doing engine work.
personally i would pull the head off and see whats what before replacing the engine, if the bits of the plug are still in the cylinder bore with no damage to the piston, cylinder lining, turbo, etc. then just get another head and fit that. or get you original head retapped bigger and just use a larger diamiter thead plug, if the valves are ok. you might be lucky.
or if nothing else pulling the head of will give you a lot more confidence to tackle lager engine issue than you are used to.
or just for sh*t and gigles.
time to learn lots very quickly.

[miller]

If you are braving an engine swap your self Ill come and give a hand for a few hours no problem.....even if it is to just throw spanners and give abuse!

[elnevio]

Given that the diff on its own took a while too long, I think I'll be using alternative means!


But of course, thanks for the kind offer!

[stu]

Given that the diff on its own took a while too long, I think I'll be using alternative means!

A "nutter" from Tring by any chance.

[elnevio]

Done and done! And I am a happy boy!!

The engine is in and running beautifully - and much better than before when my old engine was not misfiring too. Also picked up whilst being changed was the condition of the autobox. The torque converter had play in it (or the shaft did, whatever the culprit was), so that's been changed as well to the one that was with the replacement engine anyway. Now have a matching gearbox ECU with it too, plus a 7203 engine ECU to boot!

The whole system has had the cambelt/waterpump done, plugs changed, newly-cleaned injectors installed, all coolant changed, Amsoil SSO 0w-30 engine oil, Amsoil ATF for the gearbox, torque converter seal changed. One of the urethane engine mounts has been installed (the difficult driver's side one). Unfortunately, I hadn't received the set in order to get them installed into the mounts while they were out/available, but I am only left with the three apparently slightly easier mounts to do.

Next step will be to rolling road the car on a Dyno Dynamics roller to get a new baseline figure, before any boost-raising happens. It is however quite savage as it is!