Hi Bob,

You stated you might have disturbed something?

You say you replace a vacuum hose on the controller of which is of Chrysler fame.
The fame comes from the connector that has one way one time terminals inside it.
It’s the only link to the outside world other than that one hose that sucks! 😉

Our 240’s have a long life history of a few mistakes but that hasn’t lessened the joy of owning something reliable and repairable by using common sense.
No need to have a large wad of money, from an already scrimped wallet, to make payments for some shop with specialized equipment.

I have a 1986 and my 1984 after my 1986 year with that same controller.
I had a problem with losing spark on one or the other a long time back.

I’d say it was my 1986 that I learned my lesson on about that plug. Do not remove!
I think it had a yellow(?) wire in that connector too.

It was not making a good connection inside caused by me wanting to service the terminals with corrosion preventive.
I ended up cutting one corner of the connector away and soldering the wire onto that pin and having the rest of the plug fit back around the whole affair.
I never touch those connectors again! Maybe I spray something only any more.

I suspect a previous owners mechanic or you may have pulled on the that plug like I did and now you got the gremlin.

I believe it was the wagon that also had issues with the wiring harness going up to the gray connector on the ‘86.
A harness goes down around the engine on all these 240 cars since the beginning before 1978, my oldest car.
Starting with the LH 1.0 and going away from the K Jet system, they made that harness carry different wiring of course!
That’s where the idea of biodegradable insulation has come into play or not compatible with engine cleaners? Take a pick.

My 1984 had its harness rebuilt, I have discovered later, prior to me getting the car.
So, I’m pretty sure it’s now 1986 since thinking it through.

If your wiring harness under the engine going over the controller looks to be original I would say it’s a prime suspect.
Check the wires individually to the controller to see if anything wiggles down inside the connector.
Only pull that plug as a last resort no matter what you do like I had to solder mine back.
I tried to pinch them a little but even that didn’t work on that yellow wire and I think it was the heart of the system.
It might be going indirectly over to the distributor where the Hall Sensor is located beneath the rotor button.
That I don’t know.

The Hall sensor has a reluctor vane wheel in front of a coil of wire. The pluses may go to the controller one way or the other but for the most part they have be very reliable for me.
It was step towards the CPS and other proximity sensors use today in most every thing.

But now, that rotor button above it all can fail due to a crack developing under the sealant to the outer tip. So, on all these distributor cars, carry a spare.
Note:
This is the same distributor system or package used way back to the beginning of Volkswagen’s beetle. Only they had a breaker point gadget and a condenser. Both failure items besides the rotor button’s hidden identity.

On my 1984 only it has two separate relays under the glove box. One for injectors and the other for fuel pumps.
They are interchangeable in case the pumps do not run.
I swapped them around once to verify that one bad when the fuel pumps ran again.
So I opened the bad one up, with my handy LeatherMan and tied a shoe string around the contacts to get back home from downtown.
The pumps or the injectors will be on constantly with the string.
So, you have to pull the fuse or pull the relay back out until you find another relay.

You can look on the sides of the relay on this car and see a diagram.
Some relays today leave you hanging with part numbers only. I hate that planned obsolescence thinking.

On later 240 cars they combined those two relays into one but the problem can still persist as we all know.
It’s harder to diagnose as one side can fail and many times it has been said “due to bad solder joints or traces on the board below.” Let alone a magnetic coil can smoke in any mechanical relay or a capacitor or resistor or integrated chip in electronic one.

Logically it stands up to a reasoning that, If it’s man made or otherwise on earth, it’s subject to change!

We also carry one of those “system” relays plus a wire or two with alligator clips.
It all for good measure to override fuel pumps and doing diagnostics by hand and mind.

It a matter of mind over matter.
If you don’t have a mind, then it doesn’t matter.

😀

Phil