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Figured I would check my plugs on my 03 vert with 88K Have done nothing but change oil and tires since new. Runs like a charm but started to buck when I get going in the morning until it gets hot. Took a plug out AC DELCO 41 974 and if I am right the gap should be .40 mine is way over that, can they be re-gapped ? Thanks
Figured I would check my plugs on my 03 vert with 88K Have done nothing but change oil and tires since new. Runs like a charm but started to buck when I get going in the morning until it gets hot. Took a plug out AC DELCO 41 974 and if I am right the gap should be .40 mine is way over that, can they be re-gapped ? Thanks
I replaced plugs and wires last year (at 78K).
Getting the wires off the plugs was the hard part.
I used special pliers. Even so, it was a battle, and some of the wire ends pulled apart rather than releasing from the plugs.
For what you are going to go through, I suggest new plugs and wires.
At 88K, it's high time anyway.
You “can” gap the iridium plugs but be ULTRA CAREFUL not to scratch the tip of the electrode! They are very delicate. The plugs should be pre-gapped, but you know how that goes.
As mentioned above get a new set of GM Performance Parts 8mm wires and plug wire pulling pliers.
The GM number was 12495519 when I bought some about 2 years ago for around $80, so this price isn’t surprising. GMPartsGiant is a reliable source. 19833387 seems to be the replacement number…
Not that costly to replace plugs and wires. Do it while you’re at it. Age may be just as important as mileage. Changed mine with just under 40000 miles, but 20 years old. Iridium plugs, GM Red Performance Wires. I would get a misfire code at times before replacing, Found a badly fouled plug from the factory. No code since.
The biggest reason to replace is that the big gaps you found are probably due to platinum pads that used to be on the ground electrodes have detached and disappeared. About half my plugs were missing the pads. Another reason to go iridium is no pads to worry about.
Figured I would check my plugs on my 03 vert with 88K Have done nothing but change oil and tires since new. Runs like a charm but started to buck when I get going in the morning until it gets hot. Took a plug out AC DELCO 41 974 and if I am right the gap should be .40 mine is way over that, can they be re-gapped ? Thanks
Maybe .040", but it would take one Helluva coil to fire across a .40" gap, which is almost 13/32"!! Yes, they could be regapped, but why bother? They're probably original, 20 year old, 88,000 mile plugs!! Treat that engine to a new set of plugs, and probably wires....
I replaced mine with AC 41-162 Iridium plugs about 3 years ago. I recall they came pre-gapped at 0.060". The old plugs that came out (AC 41-952 25171803) had very little wear after 30k miles and were around 0.060" as well. I basically replaced them just because they were because 20+ years old.
Snap-On used to make a double swivel spark plug socket that sure made removing the two rear most plugs a lot easier.
Trying to change the gap on an iridium plug is a perfect way to break the electrode internally and not know it. Then you'll have two sparks one on the outside and one on the inside that you don't see. The electrode will oftentimes slowly migrate towards the tip and when it makes contact it will no longer have an appreciable spark inside the gaseous mixture. You won't know that this is your problem but your car will misfire and you won't know why. Do not regap iridium plugs. Read my lips. In fact when the gap of a spark plug gets bigger do not regap that either. Plugs are cheap and they wear out. And do not get the bright idea to use anti-seize on spark plugs. This will turn into it concretious mixture making it impossible to remove the plugs 100,000 mi from now.
Maybe .040", but it would take one Helluva coil to fire across a .40" gap, which is almost 13/32"!! Yes, they could be regapped, but why bother? They're probably original, 20 year old, 88,000 mile plugs!! Treat that engine to a new set of plugs, and probably wires....
The voltage needed to jump the gap is more than you think. A compressed cylinder requires higher voltage to jump the Gap than and uncompressed cylinder.
C5 spark plugs were gapped at 0.060" from the factory. By 2009 the specification had been changed to 0.040"
You should not be surprised to find original plugs with a 0.060" or wider gap from wear. When I changed the plugs on my car at 76.000 miles in 2009, the originals were at 0.60" or a little over from wear.
In the old leaded gas days we changed plugs every 10,000 - 15,000 miles because they became fouled with lead deposits. Today 100,000 miles with unleaded gas is a reasonable change interval although the iridium plugs will go much longer.
The first plug I pulled was quite an effort, to the point I was afraid I would snap the plug with the torque I had to put on the rachet (3/8) should this be a concern ?? Thanks
The first plug I pulled was quite an effort, to the point I was afraid I would snap the plug with the torque I had to put on the rachet (3/8) should this be a concern ?? Thanks
You hit on the reason I decided to change mine 3 years ago with 30,000 miles. Will they come out with reasonable sweat and effort? I tried an easy to reach one first to check on the condition and ease of removal. That went OK so then I moved on to the tougher #7 and #8. Those came out OK with my SnapOn double swivel and a 1/2” drive ratchet. If they were too difficult to remove and with my low mileage plus the good condition of the OEM’s, I could have stopped and put them back in to leave the job to a future generation. This car will never see 100,000 miles with me.
Spark Plug Question
