97 xlt ignition coil problem

[tommcd]

trying to trace the ignition coil plug from coil to ?.. changed all plugs, coil still showing misfire on 3 and 5

 

[purevenom1]

change the coil wires/.plug wires? Possibly bad coil/ 4.0 or 5.0

 

[celly]

Have you eliminated the wires from the equation? Every misfire issue I've ever had was wire related.

 

[tommcd]

i changed plugs and wires and coil..before i changed the coil it said 3 and 5 were misfiring..i put in new coil and still says 3 n 5 are misfiring???

 

[tommcd]

its a 5.0 V8

 

[purevenom1]

check and make sure the wires are in the correct location on the coil. 3 and 5 are right beside each other.

 

[purevenom1]

 

[celly]

This is the diagram I keep in my glovebox (thanks to Section 525):

 

[SoNic67]

It might be the low-voltage side of the coils - the connector that is in the right side of coils. 3 and 5 I think "share" the same coil, therefore there are controlled by the same pin/wire in that connector. My connector has the side-ear broken (maybe some previous impatient "mechanic"). Here it is unpluged:

 

[2000StreetRod]

waste spark pair

Plug #3 and #5 fire at the same time in your waste spark ignition system. Therefore, a problem with either plug or wire will affect both. Since you have replaced the plugs, wires and coil I agree with SoNic67 that you may have a problem with the trigger signal electrical path from the PCM to coil #2. You may want to disconnect the PCM connector and check for continuity from PCM pin 52 (red/light blue wire) to the connector that mates with the coil. Also check for isolation from chassis ground (not shorted). You should also make sure that pin 52 does not get pushed back when the PCM connector is installed.

The causes for engine misfire are ignition, fuel injection, and compression. Only ignition matches cylinders #3 and #5.

 

[tommcd]

thank you for your help..i will be working on this shortly and let you know.. i appreciate your responses!