Misfire

[Aussie-Parnelli]

Aussie,
Could not see link to the COP checker you used.
Could you send it again?
Thanks

https://www.ebay.com/itm/154801920880

 

[djr_xr7]

Brisk plugs are the real answer. Never seize goop comes in 2 x versions. Regular and marine grade. The marine grade will handle more heat. Make damned sure the new plugs are gapped correctly.

Not sure if it's called marine grade but nickel anti-seize is the high heat as opposed to aluminum anti-seize. There is a big price difference also.

 

[Speedracer67]

Aussie,
my miss is random so will this tester see that? so at idle with the miss I would hold the test over each coil pak and see what it registers, right?

 

[Laga]

Use the nickel based product. Never use the copper based, as copper and aluminum do not play together well.

 

[Kev555]

Hi Bambam, sorry didn't catch that first time around. Possible they were drilled but on at least one its as if he overtightened or srewed it in on bad threads as I cant screw it back out with the ratchet. The plugs that are are in the car cant be gapped they are Autolite HT like picture. Would ceramic grease be suitable temperature wise and longevity?

 

[Kev555]

Worth changing to one-piece plugs. Brisk and I believe Champion also make a one-piece plug for them. Brisk is the most expensive but if you're running FI worth it. I run Brisk and break them loose/clean every year to be sure they don't seize. Use a little anti-seize as well. When I first did mine the previous owner never had them changed. Broke three getting them out. Lisle tool is a life-saver.

You might want to try chasing the threads before getting into more expensive fixes. Hard to believe someone could "F" up that bad just replacing plugs.

At least three that ive looked at the threads are well and truly goosed Dieharder as they wont tighten fully and one i had to insert with epoxy metal as a temporary fix which has worked to an extent as misfires on that cylinder are down 90 percent. Time serts is the only cure for them three cylinder anyways. The rest I dont even want to look at for the time being as theres new plugs in them apparently and theres no misfires in them

 

[Kev555]

I just saw a very good kit for repairing mine on the web this eve, The Cal Van 39300 kit looks a great professional option for a proper repair. Pity theres none on this side of the pond, Its expensive but not as much as replacing a head or having to remove it. Just have to find the best deal now

 

[DieHarder]

Here's one you might want to consider: https://www.jbtools.com/cal-van-too...MIwbWQ0YLH-AIVQZOGCh0-Sgm9EAQYAiABEgL21_D_BwE

 

[Kev555]

Thanks Die hard found that one earlier too, so far its the cheapest offer we have found.

 

[DieHarder]

You know. It's likely you're going to have to remove the heads to do this right so I'd look at buying head and front cover gaskets at the very least. I can't imagine doing all of that drilling/cutting/milling without removing them. By the time you're done might be cheaper replacing the heads.

 

[redfirepearlgt]

That sucks. You may be able to helicoil the cylinder plug holes in question. This has been done successfully on 4.6L 2V's and other similar engines where the threads have given out and blown the plug out of the cylinder. It does work well. At least worth a try before writing it off. I have personally seen it done successfully with the head on engine at a friends auto repair shop. Most of the fines will be captured in the flutes of the tap if you use the proper tap oil.

 

[Kev555]

I have every confidence that Cal Van kit will sort it out without having to remove the head, ive re-seated diesel injectors before and and done a bit of heli-coiling around a few engines but none with spark plugs after a good blow out with an airgun I'm not worried about a bit of light alloy swarf left in the chamber as ive never seen it do any harm. I watched a few you tube videos of the method to use the kit properly a few of mechanics that have used them regular so quite happy at the minute with the condition of the plug holes that it will work. With living in Ireland and very limited engine spares available for these vehicles on this side of the pond I would be looking at spending a small fortune Die Hard on replacing head or heads from US. Afraid doing job in situ is only option at the minute. Rock auto is good for head gaskets etc should I need to remove the heads to get them machined as a last resort.

 

[Kev555]

I still have a miss or imbalance at around 2000 rpm. It may still be cause of number two cylinder plug hole leaking slightly but i think it was there before the plug hole issue arose. I did notice on Forscan that the data from the knock sensors runs a bit erratic to each other, is this normal? or does it point to a rocker problem or sensor problem? Also does the variable cam timing data look normal? Any help from anybody thats familiar with Oscilloscope readings would be appreciated photo attached

 

[Kev555]

That sucks. You may be able to helicoil the cylinder plug holes in question. This has been done successfully on 4.6L 2V's and other similar engines where the threads have given out and blown the plug out of the cylinder. It does work well. At least worth a try before writing it off. I have personally seen it done successfully with the head on engine at a friends auto repair shop. Most of the fines will be captured in the flutes of the tap if you use the proper tap oil.

It seems a lot more handy on the 3 valve Redfirepearl as you dont have to re cut into the cylinder like the 2 valve. Thankfully any videos or illustrations ive found make it look very straight forward if done right and plug hole is salvageable.