Coilpack problems continue
 

So, I had a member here send me a coilpack (assumed good) and I moved it around on the driver's side (where OT and I had noticed the obvious popping noise coming from) and putting in this new coilpack did nothing to quell my low end engine shaking and idle hunting. Am I really stuck to buying all brand new coil packs and just swapping them each until I finally get rid of the low end trouble?

Re: Coilpack problems continue
 

Not necessarily Jason. Just buy one new one, the longest color, and swap it around until you ID the bad one. Only problem is possibility of more than one mis-firing. I replaced all 6 when it happened to me, but, I was working then. :rolleyes:

Glenn

Re: Coilpack problems continue
 

Look at the wires where they enter the potting on the coil pack. We have had the insulation broken on both wires allowing the firing signal to jump from one to another without firing the plug. You get that electrical "snap" when the plug is supposed to fire. Quick fix can be a liberal application of high temp RTV as an insulator.

Re: Coilpack problems continue
 

Bought a new one and swapped it around the driver's side coils to pretty much no avail. I think the car drops a little bit less than it did before, but it still drops a cylinder when it's cold. I'm positive that the sound came from the driver's side of the engine.

It never sounded like it was dropping two cylinders, but I guess I'm certainly looking at the possibility now (not cool).

Re: Coilpack problems continue
 

I'm in the same boat as you... while changing the 1 coil pack on mine fixed the major humping my svx was doing.... it still is noticeably notchy on the passenger side towards the front.

I'm going to break down and just replace my other 5.... for the long haul, ftw!

Re: Coilpack problems continue
 

This blew my mind...... My SVX refused to idle at all. hunt hunt stall was a SOP for it.

So just a couple days ago I decided to clean the battery terminals/cables due to it starting very hard. Turns out my body ground was completely hozed with severe corrosion on the screw. So I cleaned the hell out of the battery connectors on both the ground and the positive cable, cleaned the body ground wire connector, replaced the body ground screw with a new stainless socket head, and charged my battery to full.

The stalling is 100% gone. The hunting is 98% gone. When it hunts I see a voltage drop of .25v between the engine and the ground terminal of the battery and a .05V drop when at a smooth idle. It clearly spikes to the higher voltage drop at the very start of the hunting and then drops back slower. I did NOT clean the engine ground side of the negative battery cable yet so that might solve that side.

I plan to, but have not yet done a "grounding kit" to the alternator and a extra body ground to see if I can clean off that extra bit of resistance without dropping $$$$ for new battery cables.

Re: Coilpack problems continue
 

what condition are the spark plugs? what makes you think it is inginiton related?

Re: Coilpack problems continue
 

I've had this problem ever since I replaced the plugs back in May. I replaced them all a few weeks later to see if the plugs were the problem (they weren't). I had the car down to Old Tom and he identified it as most definitely a coil pack. When we were under the car fixing the exhaust, the sound was very notable from the driver's side of the car - which is why I was focusing on only driver's side coil packs. It sounded to us like only one was blown so I only purchased one new one. Alas, it must be two coil packs or something else which I can't figure out.

Re: Coilpack problems continue
 

If you'd want to borrow a couple more coilpacks I have plenty down here just let me know. I usually get up your way at least one a week or can have my folks take one back and have it at their place (maybe 5 minutes from Messiah).

Re: Coilpack problems continue
 

I had five coil packs fail over the course of a year. Thank goodness it was just one at a time. I found the bad one by removing the fuel injection connector on one cylinder at a time. If there is no spark as in no coil working then the gas isn't getting burned. So when the injector is disconnected on the bad coil cylinder the engine still runs rough. You know no change in the engines rough idle when the injector connector is disconnected on the bad coil cylinder.

I drove about 80 miles on five cylinders when the last one failed. The idle speed has to be kept up to prevent stalling and then engine seems to run well above 2500rpm. So I also did downshifting.

When I got home I realized I could have disconnected the injector. I had forgotten about this. At least then I would not have been putting unburned gas into the cylinder. Oh well. It is one tough engine even at 320k miles.

Peace,
John

Re: Coilpack problems continue
 

That is a good idea, how come I didn't think of that when I had a bad coil?:o I ended up replacing all of them when I came across a good deal for a whole set. That definatly fixed my bad idle and hiccups at low rpm though.

Re: Coilpack problems continue
 

Yeah it works pretty good. No use wasting that gas and when I think about how long I drove with the injector disconnected that was a few miles. I had the engine running on five cylinders for about two days and at least 240 miles. I wonder if that hurts the engine? As far as I can tell it still works and I can get 28 mpg. Oil usage is getting up there though.

Re: Coilpack problems continue
 

So, I now have two new coil packs on the driver's side - front and middle. The car STILL is missing when it's cold. I pulled every injector wire and the engine missed worse with every one! Something's not right here. I do have to admit though, when I pulled the driver's side back, it didn't change as much as when I pulled the other five.

It just slays me though that I have three blown coil packs! When Tom and I had the car on the lift, we could definitely tell that the coilpack that was blown was on the driver's side. Maybe a spike came through the system and blew out all the ones on that side? Who knows.

Re: Coilpack problems continue
 

From what we have seen with different members, the coil packs break down and misfire because the insulation breaks down.

Now if this happens on one coil, and you identify the offending coil, and you replace it and your engine is back to running perfect, that is good news.

However, these coils breaking down would appear to be age related, rather than event related. That is to say the individual coils did not get a hit or anything catastrophic that could cause breakage, they just wear out.

This would appear to imply that if one goes bad, all the rest are close to the end of their useful life.

Expensive and all as it must be, the long term solution is probably replace all six. :eek: Otherwise you are just tipping around and messing with the problem, and getting frustrated.

Why not buy 3? One of each length. Mark the new ones with a dab of paint. You will be able to troubleshoot all misfires because you have one of each.

If another one goes after that, then you will only have one of the three older ones to replace.

Just a thought.

Joe

Re: Coilpack problems continue
 

The thing that gets me though is that this started happening only after I replaced the spark plugs. I replaced that entire set of plugs and still have this issue.