No Fire and I have tried everything that I know

[dscherer]

1985 K5 Blazer with factory set up under the hood, started having trouble with intermittent firing. I have replaced distributor cap, coil, ignition control module, rotor button. I am getting battery to the distributor cap and the ignition fuse is not blown. any suggestions please! thanks

 

[Wes Harden]

How are you checking for spark?

 

[RaisedK5]

When I had a similar problem years ago it turned out to be the pickup coil in the distributor.

 

[dscherer]

thanks Wes, I have replaced the coil that is mounted in top of the distributor, is there another one?

 

[Wes Harden]

Yes it is on the advance plate near ignition control module. You have to disassemble the distributor to replace the pick up coil. Make easier to get a new or known good distributor

 

[dscherer]

Yes it is on the advance plate near ignition control module. You have to disassemble the distributor to replace the pick up coil. Make easier to get a new or known good distributor

so I have a coil and a "pick up coil"? I just replaced the ICM, so you are saying there is a coil next to the ICM. let me go check this out. thanks man

 

[dscherer]

How are you checking for spark?

holding a spark plug in the wire and to ground, then turn the engine over

 

[Bent77]

This is an HEI?

 

[Bent77]

 

[1-ton]

You need a special alighnment tool to install a pick up coil in an HEI distributor.

 

[Wes Harden]

Brass feeler gauge

 

[ktmoutfront]

I have had good luck with this one. In 3 vehicles with no issues.

Pardon Our Interruption

 

[1-ton]

Brass feeler gauge

I guess you could use a feeler gauge, but if the pick up coil moved while tightening the clearance would be off. The tool I was posting sets the air gap clearance, and holds the pick up in place while tightening.

 

[Wes Harden]

Have always used a brass feeler gauge. In the 70's was all we had

 

[1-ton]

Have always used a brass feeler gauge. In the 70's was all we had

It is possible the tool I am talking about was not invented yet in the 70's. I bought the pick up alighnment tool I am talking about in the mid to late 80's

pick up tool pictured

 

[Wes Harden]

Very possible.

 

[dscherer]

Update! As always one thing leads to another. My replacement pick up coil doesn't match my plug in. which leads me to my next question. Some of you have recommended just replacing the distributor which I am ready to do. Does anybody know what the 4 prong plug is that comes off of the back side of the distributor and plugs in on the pass side firewall? All the replacement distributors I have looked at does not have this plug? It seems to be something that everyone has aborted?

 

[dscherer]

I have had good luck with this one. In 3 vehicles with no issues.

Pardon Our Interruption

 

[Wes Harden]

Pardon Our Interruption

the 4 wire are EST, electronic Spark Timing. Is your truck running a computer controlled carburetor ? If your computer controls are there and working the above is the distributor you need.

 

[dscherer]

Pardon Our Interruption

the 4 wire are EST, electronic Spark Timing. Is your truck running a computer controlled carburetor ? If your computer controls are there and working the above is the distributor you need.

Boom, That it!!! thanks a bunch