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My car has developed a bit of a shake at idle. There is no surging and the RPMs are steady. However, the car shakes a bit... It's jumpy, if that makes sense.
I popped the hood inside the garage with lights off... Sure enough, I see arching, although very light and hard to see.
It's that what's causing this jumpy idle?
Ironically, these are brand new AC Delco wires with less than 1K miles on them.
😡
When I replaced my wires I bought 2 sets of these and my plug wires can't move around. I like the fact they are plastic. I did not use all of both sets. Dan
When I replaced my wires I bought 2 sets of these and my plug wires can't move around. I like the fact they are plastic. I did not use all of both sets. Dan
Just got two sets as well.
Can you post a picture of your wires to see what they look like?
Firing order is good, or else this thing would have a serious rough idle, driveability and possibly backfire. The plugs were replaced with NGK Iridium long before the wires. Those are pre-gapped anyway.
The vibrations in getting at idle are relatively subtle.
Not real easy to get good pictures as you know it is tight quarters. I use the connectors whenever I can. Dan EDIT: I really did not plan to have two four wire connectors right next to each other in the first picture. They are for 7 and 8mm wires. They can move over time on 7mm wires. They started out a couple inches apart.
Whaleman,
Thanks for the pics. That factory holder for #6 & 8 is where some of the arching is happening. Again though, it's hard to see even if the garage is pitch black.
Another thing, this morning the idle was much smoother than last night. I was ******* on the car last night. I wonder if heat is a factor here.
FWIW. When I bought my car it had newer iridium plugs.
same symptoms as yours, steady idle but irregular jumpiness. I replaced all 8 plugs with NGK copper cores and it smoothed right out.
iridium’s might last a 100k miles but might not give the best ignition.
Had the same experience with a Honda/Saturn 3.5l. Put in new iridium plugs got a rougher idle and lower mileage. Replaced them with copper cores and all was better.
FWIW. When I bought my car it had newer iridium plugs.
same symptoms as yours, steady idle but irregular jumpiness. I replaced all 8 plugs with NGK copper cores and it smoothed right out.
iridium’s might last a 100k miles but might not give the best ignition.
Had the same experience with a Honda/Saturn 3.5l. Put in new iridium plugs got a rougher idle and lower mileage. Replaced them with copper cores and all was better.
That's interested. I wonder if anyone else shares the same thoughts.
I could swing this easily. Swapping plugs are nothing compared to wires. 😠
Update on this situation: The spark plugs I ordered back in June are TR55IX. The NGK website calls for TR5IX. The 55s are pre-gapped at .60, while the 5s are gapped at .40. Factory specs is .50.
So I have plugs with a bigger gap than spec. I feel this combined with with a thoroughly heat-soaked engine is causing the arching and jumpy idle. The coil (original) may not be able to handle these conditions very well either.
I'm not sure if I should pull the plugs, re-gap and re-install, or buy new TR5 standard plugs. I'm thinking of a new coil as well...likely with a new ICM.
Of course, the wires are the ones arching.
I guess I could start with re-gapping.
Ric
EDIT: LT-1 requires TR55IX, LT-4 requires TR5IX, per NGK's website.
I don't really know this for sure but if a plug wire has been arching there is some small hole or crack in the insulation. My first guess is even if you regap and the plug now fires before the arc occurs the hole or crack in the insulation still exists. Dan
I don't really know this for sure but if a plug wire has been arching there is some small hole or crack in the insulation. My first guess is even if you regap and the plug now fires before the arc occurs the hole or crack in the insulation still exists. Dan
Copy that. In stumped as these are brand new AC Delco wires with 500 miles on them, of that. O do want to emphasize, the arching is hardly visible.
Either way, I should upgrade to Taylor's 8mm.
i had a spark arc problem with MSD’s expensive 8.5mm lt1 wires that i bought in 2002.
sparks jumped from the wire to the water pump housing.
though it didnt seem to cause any misfire or rough idle
Are the TR-55 Iridium plugs?
if so, ive had problems with them.
since iridium is expensive, they make the electrode as small as possible and it will easily foul up if an o2 sensor goes bad. At least it did on my 1993
in my case, an o2 sensor went due to crappy work when i paid a speed shop to do a cam install (they got silicone sealant bits in the engine) . I since learned to do all work myself.
i recommend pulling a couple plugs on the easier-to-pull cylinders and check for fouling
i agree that excessive gap could tax your ignition system too much
for example: my setup isnt the same, but i have to run .029” on my supercharged/nitrous setup and its a fine line between mis-fire (too little gap) and cut-outs at higher rpm (too much gap) and that is WITH an MSD-6 box and msd coil providing extra oomph)
i had a spark arc problem with MSD’s expensive 8.5mm lt1 wires that i bought in 2002.
sparks jumped from the wire to the water pump housing.
though it didnt seem to cause any misfire or rough idle
Are the TR-55 Iridium plugs?
if so, ive had problems with them.
since iridium is expensive, they make the electrode as small as possible and it will easily foul up if an o2 sensor goes bad. At least it did on my 1993
in my case, an o2 sensor went due to crappy work when i paid a speed shop to do a cam install (they got silicone sealant bits in the engine) . I since learned to do all work myself.
i recommend pulling a couple plugs on the easier-to-pull cylinders and check for fouling
i agree that excessive gap could tax your ignition system too much
for example: my setup isnt the same, but i have to run .029” on my supercharged/nitrous setup and its a fine line between mis-fire (too little gap) and cut-outs at higher rpm (too much gap) and that is WITH an MSD-6 box and msd coil providing extra oomph)
Well, I just ordered a set of Taylor Spiro-Pro. I hope that eliminates all arcing.
The plugs I currently have are TR55IX, which are Iridium factory gapped at 60. I'm tempted to go TR5 conventional plugs gapped at 50.
As for the oxygen sensors, I just replaced the upstream ones with Denso units.
One thing keeps reaffirming itself.... Heat is causing the rough idle. Electronics don't like heat. I do plan on replacing the coil and ICM for good measure after I get my current issues sorted out.
Ric
Issue with new plug wires
