GStam66

Hey everyone, I've had an electrical issue with my 2000 T/A for a while now and I'm starting to hate the damn thing.

Long story short, the car is stuttering randomly at idle, and also when I hit the gas a bit to accelerate but not enough for it to downshift. After checking under the hood, I noticed a tiny spark jumping from the passenger side valve cover to the head (or vice versa). When the spark jumped, the engine would stutter for a second.

Because one of my MSD spark plug wires seemed to be resting against the EGR provision on my headers (2nd one from the front), I assumed that after 3 years of resting near the header, the heat burned through the insulation, causing a short. The wire looks fine, not burned through, but I wrapped it and another wire (front passenger side one) in thermal tape (rated to 1200 degrees), to be safe. I started the car up, drove it around, and the stutter/spark is still there.

None of the other wires seem to be near the headers, and I don't see any other wires or harnesses that look damaged. I have no idea where the hell this short could be coming from. While I can't see the spark now, I can still hear it coming from somewhere on the passenger side. Anybody ever hear of/seen this before?

dr_whigham

iTrader: (49)

For piece of mind, change you spark plugs. I'm willing to bet one's cracked. I had the same problem with mine when I bought it, and it was 2 cracked plugs. Drove under 3k rpm fine, but mash the gas and she'd hiccup all over if you know what I mean.

GStam66

I was going to change all the plugs and wires as a last resort, due to the price/time. The spark plug wires all look good visually. Figured I should at least check all the wiring first, make sure they all look good. There's no specific RPM range where the issue happens, only when i'm idling or attempting to accelerate without having the car downshift. Occasionally it will happen when accelerating from a stop.

It's not frequent, I'd say it happens once every other stop, and 1-3 times every 15 seconds or so when parked and idling. The jerking and sputtering get more violent the farther down I push the pedal, but if I let off and try again, it works fine.

dr_whigham

iTrader: (49)

Exactly my same symptoms. Had no clue the ceramic on my plugs were cracked, on two of them. When I was taking them off, one literally fell apart in my hands.

GStam66

I'll have to take a look at the other plugs then. Interesting, never knew that was possible. I figured with bad plugs they would just misfire, or throw a code, or not work at all. Didnt consider that the current might be able to reroute itself to the head.

Thanks for the input, I'll post up an update after a wire/plug swap. Might as well throw new ones in if I'm taking old ones out. Now I just have to figure out which of the multiple gaps that GM is stating is the right one.

dr_whigham

iTrader: (49)

Stock car? Minor bolt ons? I gapped my 55's at .055

GStam66

Lid, LS6 intake, headers/OR-Y/catback, mild tune. Nothin' special really. Was considering going with the AC Delco plugs instead of the current NGK's, and keeping the MSD wires.

dr_whigham

iTrader: (49)

Stick with the NGK's and gap them at .055

GStam66

Eh, I was considering the NGK's due to the price difference between them and the Delco's, but if the plugs are already cracking or breaking down after 3 years/9,000 miles, I might go for the ones with better longevity. I'm not really planning on too many more mods for the car, maybe some suspension work, that's all.

GStam66

Update: The wire that was resting near the passenger side header was damaged internally. Silicone insulation looked fine, but they tested the current flow of the wire and it was much weaker/uneven than the other wires. Replaced the wires with new MSD's and everything is running great. All the plugs looked good too.