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F150 Lost oil, where to go from here?

1994 F150, 4.9L I6, 4X2, MT, 212K mi.

Gee, I really screwed up!

Truck started making a “growling” noise and was down power. Oil gauge read 0 psi. Unfortunately, I was on a busy back road with no shoulder and cars behind, so I had to go about 1/2 mile, uphill, to a pulloff.

The truck lost all of its oil from the oil pressure port where I had installed a mechanical gauge several months earlier. It seems to have pulled out of the compression fitting; in hindsight, the engine must flex more under torque than I had accounted for!

I got a ride, fixed the leak, and added oil. Drove it ~15 miles toward home, with no noises, but less power on hills. Engine then made a metallic noise, and stalled. All attempts to restart failed.

WHICH BRINGS US TO TODAY
Started diagnosis. Cold compression is 120-130, all cylinders, which is less than it was, but seemingly enough to run on, Vehicle has no spark when cranked! The distributor cap rotates when cranked (no idea if in time or not), and the distributor gear was pulled and no missing teeth.

Any idea what could have failed on the engine that would result in a “no spark” condition? I suspect I need a new engine, but it would be nice to have this one running in the interim.

That engine won’t ‘jump’ time, if the timing gear fails the camshaft gear will strip and stop turning all together. The cam gear is made of saw dust and Elmer’s glue.

Your engine is deceased. It has passed to the Great Beyond. It has crossed the river Styx. It should be pushing up daiseys, … this is an EX engine…

Rarely do I get the ability to pay homage to my favorite Monty Python sketch…

I doubt there is a connection between the lack of spark and the fact that you drove it a half mile without oil. If you hadn’t seen the distributor rotor turn, I’d guess the cam broke. It really doesn’t matter what caused your lack of spark because this engine is going to toss a connecting rod in a few miles IF you get it running so I think you shouldn’t bother.

So just to make clear the engine is turning over, thus the compression readings?

When an engine runs out of oil, friction builds which creates heat.

This heat raises the under hood temperature.

This excessive heat can damage the ignition control module.

https://www.rockauto.com/en/moreinfo.php?pk=49702&cc=1414572&jsn=462

And that may be the reason why there is no spark.

Tester

Yes. Compression test done cold, with a dollop of WD-40 prior to cranking. In the 118-130 range, which seems sufficient to support combustion, at least.

I’m probably replacing the engine…

Sorry to hear of your troubles. It’s always a good idea to form a couple of loops in the tubing that can act as a spring to account for any movement that the line may be subjected to. Something to consider if you add a gauge like this in the future…

Maybe hold off on that for now. Give @Tester 's comment a second look. I think he’s figured it out.

10-4 there! “Don’t make the same mistake twice…”
(Good ol’ Mother Nature: gives you the exam, followed by the lesson!)

Okay, folks, update!

Did some electrical testing. I basically ran the “EEC-IV” diagnostic procedure in the Haynes book, and came up with:

  1. Fuel pump ON when key in ON position.
  2. Test light hooked into “TACH” input on coil glows brightly when key ON, and dims when under cranking load, but does not flash.
  3. Connecting an “inline spark tester” to the coil output shows NO spark when cranking, EXCEPT when I disconnect the jumper (meaning, I guess, that I’m the one collapsing the field windings and generating some spark.)
  4. Continuity observed between TACH input at coil and TACH output from Ignition Control Module.
  5. No volts noticed when probing the PIP (hall effect) input to the ICM.

So…I think this means I need a PIP (which is in the distributor, so really, I need a new dizzy), but I’m uncertain of my diagnosis. Can anyone back me up? Tester, I think the fact no PIP input is reaching the ICM means the ICM is likely good, but I’m almost inclined to buy a replacement at $45, and return if the distributor fixes it! (Also, my year EEC-IV had the ICM on the fender, so a long way from a hot engine.)

What says everyone?

ICM = ECM ?

never heard the term, neither did Google.

ICM = Ignition Control Module.

I thought, since I spelled it out in the previous paragraph, that using the initials the second time wouldn’t be too hard to follow, but sorry I made things harder than they needed to be!

thanks thanks

Nothing personal Mr. Mean, but I find using the slang term ’ Dizzy ’ for distributor just plain annoying.

It’s been my experience that when an internal combustion engine is run without oil and stops running it’s best to give it to the junk yard and go with a factory rebuilt engine with warranty. Or buy another vehicle. Running without oil until stopping will build up such heat in the engine that the heat will warp all moving parts. I said all moving parts. I have even seen the cam holes warp and prevent insertion of new cam bearings. You can rebuild the engine but expect lots of problems on reassembly and also later when driving the car.

Is there a pickup coil in the distributor? Test it since heat will destroy it.
Did you do a compression test without then with oil?
That engine may have life left in it but running without oil will have overheated the crankshaft bearings and they will fail shortly… when you are a long way from home but you will be able to check the piston rod the is sticking out of your oil pan.
Get a crate motor and install it and remember gasoline makes it run but oil is its life blood. and coolant is like the water and shade you need on a desert.