Engine randomly missing after engine bay washed (SOLVED!!!!!!)

[RRoller123]

Just out of curiosity, I know that you covered the distributor when you washed the car, but have you taken the cap off since and taken a look inside?

[micbrody]

I did take cap off. It was bone dry. Rest of distributor also looked dry; except for trace amount of oil

[JohnMc]

I did the same exact thing on a 1980 fuel injected 124 - in 1987. Ended up costing me a catalytic converter. Got it red hot and melted it as the car was running badly and unburned gas was going into it. (The car behind me on the freeway yelled at me as i was shooting out red hot pellets from the cat). Had to take to shop and they used wd-40 (I think they used the CRC product) on all the wires. The shop also lectured me on not getting any wiring or components wet. He said that water could stay inside the wiring for a real long time. I had previously done this on a 1969 124 and had no issues.

[micbrody]

update:

I misted water while reving engine. No arcing or sparks seen.

I removed spark plugs. They all look unremarkable. I re-installed. I added dielectric grease to ceramic part of spark plugs. Went for a ride.
Initial ride was good. But within 100 yards, problem appeared again.

One new thing happened..... actually happened a few times before, but I assumed it was related to my clutch work when car acting up. I was in third gear approaching turn to side street, as I was in my turn, I disengaged clutch to go into second.... and then car engine went off. Electrical still working on dash.

Maybe JohnMc is correct in that something is still wet. The question is what????

I am running out of ideas. I guess I will try to switch out AFM. Not sure what else to look at. Maybe I should have not "misted" the cabin heater intake; maybe there is still water in there......though not sure how that would relate to this problem.....wouldn't it just blow a fuse?
The problem seems to be getting less frequent....

[micbrody]

Ok.....I just took it out again and I did find something VERY interesting. Though it seems to do it randomly......... It always does it when I am at a stop and then accelerated to make a left hand turn.......... Straight away acceleration from stop rarely does it. Occasional right hand turn...... but ALWAYS left hand turn from stop.

My two hypothesis: crude in gas tank that somehow obstructs when sloshing around sideways on turns........ though it should slosh with straight away acceleration; and why always with left turn. I did fill up tank to rule out that near empty tank was causing fuel delivery interruptions when sloshing around.

My more likely explanation: There is a wire that is grounding out; probably not fused as it would have blown fuse. So that probably means ignition system? I did add some relays for head lights and ignition to bypass ignition switch. Maybe a relay got wet?
Maybe the steering linkage is hitting one of the major wires to and from starter; the main ground; etc......maybe clutch cable shorting something......

I'm done tonight..... gonna have some wine......wait for some wisdom from the board.......

[BwBrown]

Sorry, this got long.

An engine under load is more susceptible to a diminished electrical system. It is more likely to hiccup under load than at idle when there is an abundance of reserve power in the electrical system.
I would still be inclined to suspect the high tension wiring - distributor, coil and spark plug wires.

Your most recent observation about left turn/right turn made me wonder - how well are your spark pug wires anchored or routed? Could a slack wire be waving about under the hood coming into contact with a ground allowing an arc?

All that said, the last time I had a serious power loss under such circumstances, the starter motor was loose, on a turn would lean to one side and short out. The weird part about it, and the reason it took several weeks to figure out, was actual starting pulled it tightly into place - and there were no other symptoms.

While the water may have made your problem show its ugly head, the grease and dirt you removed may have actually been your friend, insulating or hiding a pre-existing problem.

I would go back to your evening (low light conditions) idle, take a longish insulated stick and gently move wires around, try to wiggle components, coil, relays, relay connections - you might get lucky and find the offending spark arc. You might find a tiny crack in a spark plug wire, or a carbon arc in or on the distributor cap - many such offending carbon traces are to small to see under normal lighting. Clean the inside of your dist cap with solvent (wd-40) and a Q tip You may be surprised how black it gets from carbon as the center electrode wears. Some carbon traces will only arc under load, when that trace becomes the path of least resistance.

Check your coil for loose mount, and wire tightness on the terminals. It really sounds o me like something in or around your motor is dancing in the wind, sort of "waving while you work."
Good luck, and I recommend a nice white wine.
Bob;

[micbrody]

BwBrown,
Thanks for the long post.

Tonight I jacked up front end and turned the steering wheel left. the steering linkage would touch the speedo cable, which was also very close to the transmission to chassis ground.

I also noticed that the red wire connected to solenoid was fairly close to the hot wire on starter stud; and there was electrical tape that unpeeled a little off the the red lead. My theory was that this "loose" piece of electrical tape (gooy) was occationally touching hot lead on starter, causing a resistive short to ground. I removed the leads rotated their mounts so their crimped ends would be farther away from each other. I then coated with liquid electrical tape. Went for a run:
Still had same problem.....though everytime seems less frequent. I still can produce it with left hand turns 100% of the time; still occasional other ways.

My next theory:
The ground from transmission to chassis is bad. Question: What is the purpose of this thick ground? With all the grounding pods, why is this one needed? Is it the ground for the starter? If so, then it should only effect starting ?

As for loose starter motor.......is there a way to feel it? where are the mounting screws/nuts?

[RRoller123]

It is a really good idea to add a precautionary second engine ground; I went from the firewall, exhaust side, to one of the unused AC pump mounting spots on the block.

[spider2081]

What is the purpose of this thick ground?

The battery's negative terminal in your car is connected to the chassis in the trunk battery box. The engine is isolated from the chassis by the rubber engine mounts and the transmission output shaft by the rubber doughnut. So the engine with the alternator mounted to it are not assured a good ground return to the battery, The heavy ground wire connects the engine/alternator ground to the chassis ground that connects to the battery negative terminal. This completes the electrical circuit for the alternator to charge the battery and the battery to start the car. The alternator's ground to the chassis is very important for the charging system to operate properly. This is why many manufacturers have a heavy ground wire from the alternator case directly to a the battery or chassis ground. An example: if there is 0.5 ohms resistance between the alternator's case and the battery's negative terminal (0.5 ohms is too small to be measured by most multi meters) and the battery needs 5 amps to charge not enough voltage reaches the battery to fully charge it. I have seen cars that the owners painted the alternators and then the mounting hardware was unable to make a good electrical ground connection. This caused the battery to be under charged for starting the car.
Adding a #10 or larger ground wire from the alternator case to the cars chassis can only improve the charging system it should never hurt it.

Any chance your carbon canister has water in it???

[micbrody]

As for carbon cannister with water: theoretically..... but problem happened immediately after filling up gas tank; so if there was a "negative pressure" in gas tank affecting fuel delivery, it was immediately relieved with fill up..... and should have taken many minutes of driving to build up more negative pressure.

The more I think about it, I think the big grounding cable is the culprit. Though there are other grounds on engine, the main one that services the engine block is the big one. So when spark plugs under full load and compression, there is not enough ground to block. (Of course, this is my 5th "sure thing" reason for my problem).
When I inspected, the soldered/welded part to chassis is intact; but i can totally imagine that there is lots of corrosion around the contact points. So when I make left hand turns, the ground wire is knocked by steering linkage, and that causes intermittent contacts........ at least that's my current theory.

RRroller: can send pictures to show where on firewall and engine you added ground?

[AriK]

I got mine here.

[micbrody]

AriK,

Where is connected on engine?

(Love the colors of everything!; do you photo of entire engine bay?)

[RRoller123]

Water in the gas? Add some dry gas?

[micbrody]

Gas tank was near empty when problem started. Filled up; still problem ......and why always on left turns...... so I doubt water in gas


As for dry gas, I have plenty ......wife would like me to dispose of my dry gas in a more useful way

[AriK]

AriK,

Where is connected on engine?

The braided wire leads to a cambox bolt which holds the accelerator linkage.
Another one connects from the air pump stud to the frame rail.




(Love the colors of everything!; do you photo of entire engine bay?)
Going off-topic here's a shot of my engine bay

Micbrody, I would not tamper with the weld on your 36 year old chassis. Clean up the bellhousing connection and add at least one solid ground connection such as I have and seek for hopeful improvement.