Join 3,559 readers in helping fund MetaFilter (Hide)


How do figure out what spark plug wire goes where.
June 3, 2010 2:51 PM   Subscribe

Everything I read said 'Don't mix the wires up.' I mixed the wires up. How can I get this truck running?

I have a 88' GMC S15 6CYL truck. I was replacing the spark plug wires and got them out of order while removing the old ones. Now, I'm not sure what to do. The repair manual says the firing order is: 1-2-3-4-5-6. It even has a diagram of the distributor cap and the cylinders, but the distributor cap in the digram only has six points. Mine has seven, one extra in the middle. I think the seventh point in the middle is the one that gos to the ignition coil, I'm not sure. Does anybody know, or know how I can find out?

It seems like it should, but I think I remember the center wire going to point #1. I wish I had taken a picture.
posted by itsamonkeytree to Sports, Hobbies, & Recreation (6 answers total)
 
The middle one is to the coil.
posted by Big_B at 2:54 PM on June 3, 2010


Are you clear on where #1 goes on the cylinder cap? If not you may need to get cylinder 1 at TDC to make sure you are putting the plug on the right spot on the distributor.
posted by Big_B at 2:57 PM on June 3, 2010


Yep, the middle one goes to the coil. The middle of the distributor accepts the spark from the coil, and distributes it to the various cylinders whose connections are around the outside edge of the distributor cap.
posted by jon1270 at 3:06 PM on June 3, 2010


I'm pretty sure I have #1 right on the distributor cap. The diagram seems clear. It put #1 facing the rear of the engine next to the fastening bolts.
posted by itsamonkeytree at 3:07 PM on June 3, 2010


A quick tip:
No matter how many tune-ups you've done, always replace plug wires one at a time. If you're replacing the distributer cap too, remove the old cap with the wires attached, install the new bare cap on the distributer and then match the wires up one at a time.
You can rest assured that you're not the first person to make this mistake.
posted by Jon-o at 4:28 PM on June 3, 2010 [1 favorite]


You can rest assured that you're not the first person to make this mistake.

Hell, no. Writing the numbers on the leads and/or cap with a paint pen if there is going to be any significant delay between taking them off and refitting is well worth it, too.
posted by Brockles at 9:05 PM on June 3, 2010


« Older My far-flung co-workers and I ...   |  What are the options for resid... Newer »
This thread is closed to new comments.