RPetty_43

I knew it was something simple and right in front of me. The intermittent part was random and frustrating though as the vehicle would run fine from time to time, though it was never running perfect. After pulling the plugs and tracing the firing order cylinder by cylinder, using compression, I was certain of the firing order. And as I said many times, the truck ran from time to time. So I was certain all the basics were in order. I noted the plugs were wet which told me either the injectors were stuck or the proper spark was not there under compression. The spark tested fine using an HEI tester, but the spark was thread thin. I didn't like it although several sites showed that was normal. I then grounded all the ignition components using jumper wires and still nothing. So I thought, OK, which came first, the fuel flooding or no spark causing a wet plug? How do I trouble shoot this? If I take the spark away, of course that will create the wet plug. It then dawned on me to take the fuel away and I'd be the lone fuel source with a can of ether. I disconnected the fuel pump relay, relieved the pressure in the fuel rail, and cranked it over while spraying ether down the throttle body. Nada, not even a flicker of life. Now I knew for certain it was spark related. I checked the wires for resistance and all checked out. However, when I pulled the coil wire I noticed, for the first time, that the nipple had come off the coil. Where did the nipple go? It was stuck in the coil wire. I took needle nose pliers and removed the nipple and replaced the new coil with the old one. It fired immediately. So here's what was going on. The new coil had a crimped on nipple that was loose causing to much resistance. It worked ok when I first installed, but soon caused issues. When I reinstalled the old coil, the nipple came with the wire and though it seemed like the wire was fully seated in the old coil, it was not, causing slightly higher resistance. Damndest thing I've ever seen. A friend told me that he has actually made his own coil tester by connecting two plugs in series using a piece of plug wire. If he gets spark through both plugs, then the spark is good. And he's had cases where the first plug would spark and second was cold proving the spark would be too weak to fire under compression. Anyways, as is typical with any automotive problem that has several bad components, it sometimes takes thinking outside the box, and a lot of patience. My wife told me there was a reason the truck was sold in a "not running" condition and to sell it. I said that it didn't make sense and that I'd figure it out no matter how long it took. The truck now starts on the first click of the key. Issue solved and job done. Minor issues were older gas, TPS, water temp sensor, and intake air temp sensor. Major issue was a faulty coil nipple, which came off in the coil wire causing trouble with the old coil as well. This also confirmed what may were saying on this site, that a hard or no start issue with the F-150 is 99% surely an ignition issue. Nothing in all the tests I done showed that until I peeled the onion a little further. As I'd been saying all along, it's got to be something right in front of me and so simple that I'm just not seeing it. Never, ever give up. Compression, fuel, and relatively closely timed spark should net you a running engine.

Tristin

Can you take a pic of the nipple you were talking about?? i think im having the same problem

RPetty_43

It looks like the end of a spark plug.



I found that this connector had become loose and found it stuck in the end of the coil wire. All that remained on the coil was a pin-like protrusion that this nipple was supposed to be solidly attached to. Worse was that when I pulled the wire and connected to the old coil, the nipple kept the wire from fully connecting.