Spark Plug Wire Diagram

MERCURY COUGAR
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REVISIONENTERPRISES
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1987 Cougar XR7 = 5.0 V8 = 138k miles

I just failed a state mandated smog test. The technician showed me a loose spark plug and told me the timing was off.

Before adjusting the timing, I decided to replace all plugs and install new wires since it has been a few years.

My son wanted to help . . . before I could make a note of wire-to-contact placements, he had removed all of the old wires.

We put the new ones on where we thought they best fit according to length, but when I started the car, it ran extremely rough. Putting it into gear stalled it.

We tried chaging a few, but without improvement.

We tried to recheck the timing, but moving the distributer only worsens the rough idle, or causes a quick stall.

There was nothing wrong with the way the car ran before the smog check. I'm the original owner and it has been on a fairly regularly scheduled maintainence, without any major problems.

Since I have your attention, assuming its NOT the timing, is there something else that may be causing the engine to run so roughly?

I'm hoping all we need is a diagram showing proper spark plug wire placement at cylinder and distributer connections.
Nov 29, 2007 at 4:49 PM
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BMRFIXIT
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https://www.2carpros.com/forum/automotive_pictures/99387_rx7_1.jpg

Nov 29, 2007 at 7:24 PM