contribution test #4 cylinder failure

[deezelfromRofo]

i just redid my valve cover gaskets, uvch, connectors above valve covers. could switched up wires cause this failure? was running good before swap. running rough and blowing white smoke under load. wont let me passed 1500 rpms now. guess i should recheck wiring anyone else experience this after swap? thx Josh

[dazdillenger]

are you saying you may have reversed the leads on the injectors? As in, #6 on #4, and vice versa? That would be bad. Get that pulled apart ASAP.

[alberta 7.3]

I'd re-check the wiring just to be sure nothing was crossed, and no exposed wires are shorting. Check to make sure the UVCH wiring is clear of rockers and pushrods, some guys have had wires rub and short out. I'm assuming you did just the 2/4 connector?

White wire-injector #2, connector pin 4
Brown/lt blue wire-injector #4, connector pin 2
pink/yellow wire-injector common, connector pin 3
Pins 1/5 are GPs

What was the truck doing before you did the work to it? Does it only smoke when under load?

[deezelfromRofo]

It only smokes under load. Before the swap it threw a Cel. Idled rough for a few seconds then cleared up. I pulled the covers and found the gasket was melted close to fire wall drivers side along with harness. Could you explain all of the connectors like your explanation above including wire colors. Thx so much Bill. Your knowledge is appreciated.

[deezelfromRofo]

Also which side is which if your standing in front of truck and whats the cylinder order. Thx.Josh

[alberta 7.3]

Cylinder layout:
7----------8
5----------6
3----------4
1----------2

P--FRONT--D


This is the connector for injectors 2 and 4. The picture view is of the outer harness connector, looking at the face of the plug, not the backside where the wires enter.

[deezelfromRofo]

Update! Finally got the truck straightened out. Running like a top again. thx for the help fellas. Feeling good

[sgt dave]

What was wrong?

[alberta 7.3]

Good to hear you got it fixed

Did you have some wires crossed?

[deezelfromRofo]

Had a loose wire. Thx again Bill your schematics were right on.