What is the location of the number 1 spark plug wire male prong on the distributor cap? It looks like whoever last worked on the distributor cap and plugs mixed the wires up, the order makes no sense. I know the firing order is 15426378 once I know where 1 is at I can put it all back correctly going clockwise. How do you disengage the vacuum advance? That would help me set the timing. The truck is an 89 5.0 efi f150

Thanks

 

Alrightythen...

#1 spark plug is passenger side front.
Distributor turns counter clockwise.
It's EFI.. there is no vacuum advance.

If you do have a vacuum distributor in the motor then that's a problem and first thing you need to do is find a TFI equipped 5.0 EFI distributor. Then bring #1 piston to TDC on the compression stroke and insert the dizzy so the rotor is pointing at the #1 post on the cap when it's fully seated. The TFI module should also be at about the 5 O-clock position when viewed from above and the crank timing mark at 0 on the balancer.

Then start the motor and let it warm up and the idle settle down, attach your timing light and remove the spout plug(grey plug in the TFI wiring harness) to disable computer controlled ignition advance, set the base timing at 10-12deg by rotating the distributor, then tighten the hold down, re-insert the spout, and disconnect the timing light.

 

Thanks Conanski, sorry about that, I meant electronic advance, I'm used to doing this stuff on older cars. Does anyone have a picture of this gray plug? I recall seeing several. Also I was aware that it was the passenger side front. Which prong does it go to on the distributor cap though? I know mine must be hooked up wrong, I traced the #1 cylinder/plug wire to the distributor cap and someone has a 5 written next to it... and the plug wire is hooked up to a prong on the drivers side towards the rear...

Thanks

 

The spout plug is always in the TFI harness and would be on the passenger inner fender on trucks with a remote mounted TFI module, but your truck doesn't have that so it the only grey plug hanging out of the harness near the TFI connector.

#1 post on the cap will have a dot, arrow, or 1 next to it.

 

Just a thought - If by chance you are used to how the cylinders are numbered on say, a small block chevrolet, then you will get what looks like a weird firing order on a small block Ford if you try tracing the wires back to the cap.

Ford goes by sides 1-2-3-4 and then the other bank is 5-6-7-8

Chevrolet starts at the front and then alternates banks for 1-2-3-4-5-6-7-8

To mix it up a little further, there are also two different firing orders on the Ford 302, depending upon the cam.

Just a thought to explain the firing order that you came up with

David

 

Here's a link with some pics...

EFI Distributor Installation and Initial Spark Calibration

 

Thanks man, that made life much easier for me. What are the timing specifications for my truck? I have a haynes manual, which says to check my emissions decal... well... the emissions decal is no longer on the truck for some reason...

 

Stock timing spec is 10deg adv but many engines wil tolerate 12-14deg on 87 octane and that will give a little more spunk and milage.