Coil, Leads and Plugs

[NachaLuva]

I have decided its time I pull my finger out & fix my engine's misfire. It has been given new plugs every service but still has the original coil pack & leads. I was gonna get new leads & look at those iridium plugs but remembered about a coil conversion? Can someone please tell me whats involved & of course the costs lol. I'm guessing it will use different leads so I'll hold off on doing that till I know more.

Also what do people think of these iridium plugs? Worth the extra cost?

Anything else I should do? It misses noticeably at low rpm & is I think a fair bit down on power from what it should be. Plus it doesn't get the fuel economy that others have reported despite my (usually lol) conservative driving.

EDIT: I have a '98 Forester, EJ20 NA, 160,000kms

 

[Rally]

Ignition systems which give problems generally do it in 2 ways- poor starting and high RPM/high load misfires. How many k's have the leads and coil done? I'm not sure what model you have, but the standard coil should be good enough for most applications unless it is faulty. While it is always good to give the ignition system a good look over, you should also be sure it is the ignition system. Could there be an injector issue? Has the car regularly been given the fuel additive and upper cylinder cleaner? And has the air filter been checked? Also, check the fuel filter and also check for a missing or damaged vacuum hose.

I run platinum plugs in my Forrie- have never used the iridium plugs so cannot comment.

 

[NachaLuva]

I recently gave it the upper engine cleaner, got a heap of smoke but I'm a bit reluctant to do it again with all the trouble Taza had after he did it.

I regularly use injector cleaner. I've wondered about the EFI fuel filter. I know that in other cars they block if you run the fuel down low, which I have done a few times. So I might change that. It has a new air filter. Havent noticed any missing or loose/damaged vacuum hoses but I'll go have a thorough look.

How do I check if the coil is OK? I dont wanna get new leads to find I need a new coil & so do a coil conversion needing new leads.

My receipts say NGK plugs, set of 4 for $16. I'm guessing they're just standard plugs. I did pull one out few months ago & it looked good but they have been replaced every year & the car is overdue for a service.

Should I get platinum or iridium plugs or stick with standard. I read somewhere they need to be the resistor type???

 

[Rally]

What happened with Taza?

You can't easily check the coil- but if it is faulty, it would most likely have difficulty building voltage. Your plugs will be a guide as they would be black and sooty- maybe even wet. the thing with ignition systems is that they will break down under load. At high RPM's, there is very little time for them to build up the voltage. In addition, cylinder pressure are much higher so more voltage is required to jump the gap. However, it is not voltage that ignites the fuel- it is current that ignites the fuel. Your spark plug will dob in a dodgy lead or coil. If all plugs are showing signs, then chances are it may be the coil. If one plug is showing signs, it is more likely the lead. But your problems are at low RPM, so it would seem to me to be a vacuum or fuel issue. I think it was Kevin who had an issue a while back with mud around one of his injectors?? He might care to comment. There is also a strainer on the fuel pick up- but again if there were fuel blockages this would cause a lean out at higher revs. How long has the engine been playing up? (Time and k's)

 

[taza]

What happened with Taza?

Rally since using SUEC my burning oil situation has become alot worse. Before I would top it up with 300-400ml every 5000km. Now I have to top up 500-600ml every 250km

I did have other issues which resulted in a few sensors being replaced and cleaned aswell as a timing belt and water pump replacement at 163,8000km. (currently 164,400km)

How is the situation after what I said on AuSubaru Matt?

Cheers
Taza

 

[Rally]

Ah, that rings a bell now. Had your car always had the SUEC treatment, or was it the first time is a long time?

 

[taza]

Ah, that rings a bell now. Had your car always had the SUEC treatment, or was it the first time is a long time?

For me I bought the foz June lst year with 119,000km and now 164,400km. To the best of my knowledge it had never been done except at 10,000km. The timing belt was a botched job also when done by the previous owner using acheap chinese belt and just doing the belt. No bearings or water pump. Thus me spending a fortune getting her sorted.

So thats 150,000km without it...

Im going to have to do the seals soon, just going to wait until im sorted out at uni then get it done or do t myself with the help of some other Subaru Enthusiasts

I am keeping a close eye though as I don't want to sieze her and be up for a new engine, especially after all this work and money put in.
Rally is there any other way to help preserve or restore the seals? For the mean time.

Thanks,
Taza

Sorry Matt for the thread Hi-Jack but if your foz is in a similar way you could be heading to where I am now

 

[NachaLuva]

For me I bought the foz June lst year with 119,000km and now 164,400km. To the best of my knowledge it had never been done except at 10,000km. The timing belt was a botched job also when done by the previous owner using acheap chinese belt and just doing the belt. No bearings or water pump. Thus me spending a fortune getting her sorted.

So thats 150,000km without it...

Im going to have to do the seals soon, just going to wait until im sorted out at uni then get it done or do t myself with the help of some other Subaru Enthusiasts

I am keeping a close eye though as I don't want to sieze her and be up for a new engine, especially after all this work and money put in.
Rally is there any other way to help preserve or restore the seals? For the mean time.

Thanks,
Taza

Sorry Matt for the thread Hi-Jack but if your foz is in a similar way you could be heading to where I am now

No that's fine Taza, its relevant for me too. But which seals are you meaning?

BTW mine's done 168,000kms so we're very similar lol :iconwink:

It's had regular servicing since new but I don't think its ever had SUEC till I did it.

Taza, car's still the same, haven't done anything yet. I wanna find out what I need to do 1st.

Rally, do you know where the fuel filter is? I cant find it.

 

[Rally]

Fuel filter as marked. Ignore the rest of the fuel system- this is a photo I had on file of my WRX with an upgraded fuel system- but the fuel filter is as it would be in the Forrie.

There is a chance there was so much build up in the system that the SUEC may have dislodged a chunk- but that is just pure conjecture. Maybe the rings were so full of gunk which prevented them from moving. Compression good?

 

[NachaLuva]

Fuel filter as marked. Ignore the rest of the fuel system- this is a photo I had on file of my WRX with an upgraded fuel system- but the fuel filter is as it would be in the Forrie.

There is a chance there was so much build up in the system that the SUEC may have dislodged a chunk- but that is just pure conjecture. Maybe the rings were so full of gunk which prevented them from moving. Compression good?

That's the fuel filter? I thought that was just the charcoal cannister!

OK, I'll price a new one...

Thing with the SUEC is I havent noticed ANY change since doing it although that would explain Taza's probs. His compression was awesome!

I have no idea what my compression is like.

 

[Rally]

Be sitting down when you do...

Charcoal canisters won't have hoses with hose clamps on them. None that I've seen anyway. Be very careful when removing hoses- let the car sit overnight to let the fuel pressure come down. Make sure you have plenty of money for swear words- you may need a loan as these things can be a bugger to remove. I have hose removing pliers for that reason.

That's the fuel filter? I thought that was just the charcoal cannister!

OK, I'll price a new one...

.

 

[NachaLuva]

Decided not to do a coil conversion...

Put in Iridium plugs

Got new leads but the 2 right angle boots dont fit all the way on. So I checked out 2 other brands...same deal. So I called Subaru for a price on genuine...$36...EACH!

Many & varied swear words later, I still don't know what I'm gonna do. Worst thing was the Bosch set were a nice blue, not the boring black

Has anyone else had the boot problem?

Be sitting down when you do...

Charcoal canisters won't have hoses with hose clamps on them. None that I've seen anyway. Be very careful when removing hoses- let the car sit overnight to let the fuel pressure come down. Make sure you have plenty of money for swear words- you may need a loan as these things can be a bugger to remove. I have hose removing pliers for that reason.

Damn straight they were a bugger...so I just cut em off! lol :lol:

One was a little damaged anyway so I figured couldnt hurt to put new hoses on.

Good advice about letting the car sit, very little fuel spilt...thanks :biggrin: